Concrete Magazine - Volume 55. Issue 03.

concrete VOLUME 55 ISSUE 3 MARCH 2012

Coming Home to Concrete campaign provides concrete answers

Residential Concrete Slab-On-Ground quality without compromise

Concrete Homes Europe, Australia and the Middle East

THE MAGAZINE OF THE CEMENT AND CONCRETE ASSOCIATION OF NEW ZEALAND

UPFRONT Welcome to the first issue of Concrete magazine for 2012. With quarter 1 almost complete the wider building and construction sector has already seen a tremendous amount of activity.

concrete MAGAZINE

Editor/Advertising: Adam Leach +64 4 915 0383

Regulatory changes stemming from the Canterbury earthquakes of over a year ago continue to emerge - specifically the end of the transition period for all NZS 3604:2011 concrete floor slabs constructed on ‘good ground’ to be reinforced with a minimum of 2.27 kg/m2 of grade 500E reinforcing mesh fabric that conforms with AS/NZS 4671:2001.

adam@ccanz.org.nz

In addition, all perimeter foundations are now required to be tied to the concrete slab with reinforcing steel. This requirement also applies to NZS 4229:1999 floor slabs.

concrete is published quarterly

To help builders better understand these Building Code changes, as well as provide guidance on good practice in relation to robust and resilient concrete slabs in general, CCANZ has produced Residential Concrete Slab-On-Ground Floors, an easy-to-read 12-page leaflet. A copy is enclosed with this issue of Concrete magazine.

Association of New Zealand)

The leaflet is part of the Coming Home to Concrete campaign, which has been designed to raise awareness of all aspects of the advantages of residential concrete and concrete masonry construction.

Wellington

Coming Home to Concrete makes use of film, print and online media to demonstrate the possibilities that can be achieved through the use of concrete and concrete products in our homes. A copy of the campaign booklet and DVD are also enclosed with this issue of Concrete magazine.

Complementing CCANZ’s traditional technical role as first port of call for concrete information or concrete answers - the Coming Home to Concrete campaign is CCANZ operating in a more accessible sphere, conversing with the consumer, the prospective home builder, renovator or rebuilder, outlining their concrete choices.

A further dimension to CCANZ‘s ever expanding area of operation is the upcoming Concrete Futures campaign. With Damage Resistant Design a current topic of intense discussion following the Canterbury Earthquakes Royal Commission of Enquiry’s hearing into future building technologies, CCANZ has scheduled for May/June 2012 a programme to showcase the aspirational structural options available to our engineers.

Encompassing PREcast Seismic Structural Systems (PRESSS), Base Isolation and Non-Tearing Joints (aka. Slotted Beams) the Concrete Futures campaign will illustrate how innovative approaches to multi-storey structural design using concrete systems can help ensure resilient multi-storey building for seismically prone areas across all of New Zealand.

The campaign will utilise current examples of PRESSS (Southern Cross Endoscopy Building in Christchurch and the Alan MacDiarmid Building in Wellington), Base Isolation (Christchurch Women’s Hospital), and Canterbury University research work (Non-Tearing Joints) as case studies to articulate the role concrete systems are today playing in tomorrow’s buildings.

Subscriptions: Kylie Henderson +64 4 499 8820 admin@ccanz.org.nz

by CCANZ (Cement & Concrete

PO Box 448 Level 6, 142 Featherston St NEW ZEALAND Tel: +64 4 499 8820 Fax: +64 4 499 7760.

Email: admin@ccanz.org.nz Website: www.ccanz.org.nz ISSN: 1174-8540 ISSN: 1179-9374 (online) Disclaimer: The views expressed in concrete are not necessarily those of the Cement & Concrete Association of New Zealand. While the information contained in the magazine is printed in good faith, its contents are not intended to replace the services of professional consultants on particular projects.

The Association accepts no legal responsibility of any kind for the correctness of the contents of this magazine, including advertisements. © Copyright 2011 CCANZ (Cement & Concrete Association of New Zealand)

I hope you enjoy this issue of Concrete magazine, with its residential focus, and I look forward to sharing with you our Concrete Futures work in the next issue.

Rob Gaimster CCANZ, CEO

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Cover photo: Residential house. Glencoe Construction Ltd.

NEWS

NEWS NEW GM FOR GOLDEN BAY CEMENT Michele Creagh has recently been appointed to the position of General Manager at Golden Bay Cement.

Michele first joined Fletcher Building in 1998 as the Business Unit Leader for Plyco Doors. She then spent a couple of years in the role of GM Building Products Landscape for W. Stevensons until she returned to join Firth. Whilst with Firth, Michele held positions as National Marketing Manager, Dricon GM and latterly South Island Chief Operating Officer.

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Michele Creagh

Michele recently completed an executive programme at Stanford University, is a graduate of Transformational Leadership 2 and holds an MBA. Michele sees her appointment as an opportunity to contribute positively to the growth and future direction of the company, with the immediate goal being to ensure the continued success of Golden Bay Cement, in what is currently a very difficult market.

CCANZ ANNUAL REPORT The 2010-11 CCANZ Annual Report was presented at the 2011 Annual General Meeting held recently in Wellington, and is now available on the CCANZ website – www.ccanz.org.nz Reporting against the CCANZ Strategic Plan, the document outlines achievements within the following areas - Baseline Activity, Communications, and Projects.

During the initial formulation of 2010-11 CCANZ Annual Report the 2010-11 Business Plan priorities revolved around a revitalised project schedule that addressed relevant issues and offered outcomes of genuine benefit to a concrete industry struggling amidst the recession. This was most evident in the assignment of resources to a targeted number of complex projects with ambitious goals.

Yet despite many achievements the 2010-11 year at CCANZ was dominated by the aftermath of the Canterbury earthquakes. Not only did the Business Plan require amendment, but remaining up-todate with the numerous consultations, policy announcements and regulatory amendments also became extremely resource intensive.

While the 2010-11 year witnessed perhaps New Zealand’s greatest misfortune in the form of the Canterbury earthquakes, the impact of which has been accentuated by a struggling economy, the concrete industry must continue to proactively identify and respond to opportunities that will enable more rapid recovery.

Through astute governance, continued strong leadership and effective communication with industry stakeholders CCANZ will play a crucial role in this undertaking.

Energy Efficient Our Insulated Masonry System incorporates 40/60 or 80mm insulation board to concrete structures providing a complete thermal envelope.

This System provides for the premium Rockcote flashing suite, and plaster coatings to provide a durable, low maintenance, and most importantly energy efficient structure now and into the future.

www.rockcote.co.nz 0800 50 70 40

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NEWS

NEW FOUNDATION DESIGN CATEGORIES FOR CANTERBURY The Department of Building and Housing (DBH) has announced that three new categories for residential foundation design have been developed and will be required for repairing and rebuilding homes in Canterbury following the earthquakes of 2010 and 2011.

specific geotechnical investigation required is the simple shallow soil strength testing which is standard for all homes. A range of standard solutions are available for the repair and rebuilding of foundations in these areas.

Canterbury Earthquake Recovery Minister Gerry Brownlee said the foundation designs apply to the flat land in the residential green zone in Canterbury, which has now been divided by engineering experts into three new technical categories (TC1, TC2 and TC3).

“Property owners in TC3 who need to carry out repair or rebuilding of foundations can do so, but they will require site-specific geotechnical investigation and specific engineering foundation design,” Mr Williamson said.

The categories, and the areas they apply to, are based on ground conditions, including the susceptibility to liquefaction, and the extent of land and building damage caused by the earthquakes.

Technical Category 1 (TC1) Properties in TC1 (grey) are unlikely to experience significant land damage from liquefaction in future earthquakes. Standard concrete slabs and timber floors are acceptable for foundation repairs or rebuilds.

“Following the damaging earthquakes in Canterbury, extensive scientific and geotechnical investigation and research has been undertaken by a range of experts to identify land issues and ways to reduce the risk of injury to people and damage to homes in any future earthquakes,” Mr Brownlee said.

“This is part of ongoing work to improve building standards in New Zealand and the Government’s coordinated response to long-term recovery in Canterbury. The information released today will allow homeowners with damaged properties in the residential green zone to get on with the process of repairing or rebuilding their homes with greater confidence,” he said.

The three new technical categories are part of the DBH’s updated guidance for repairing or rebuilding houses in Canterbury following the earthquakes, which has been revised to take into account earthquakes in Canterbury on 22 February and 13 June 2011 – see following News item.

Building and Construction Minister Maurice Williamson said the three technical categories relate to the performance of flat land in the earthquakes and its susceptibility to liquefaction in any future significant earthquakes.

A map is available with the three different technical categories of land colour coded on it - TC1 is grey, TC2 is yellow, and TC3 is blue.

“The good news is homeowners whose property is in TC1 or TC2 with foundations that require repairing or rebuilding, they can get on with the process with confidence. The only further site4 concrete

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Technical Category 2 (TC2) For properties in TC2 (yellow), minor to moderate land damage from liquefaction is possible in future significant earthquakes. Lightweight construction, for example corrugated iron not tiled roofs, or enhanced foundations such as more robust floor slabs that better tie the structure together will be required for foundation repairs or rebuilds.

Technical Category 3 (TC3) For properties in TC3 (blue), moderate to significant land damage from liquefaction is possible in future significant earthquakes.

Foundation solutions should be based on site-specific geotechnical investigation and specific engineering foundation design where foundation repairs or rebuilds are needed. This might involve deep pile solutions.

For properties not in these categories, normal consenting procedures will apply. This applies to non-residential properties in urban areas, properties in rural areas or land outside the areas which have been mapped for land damage and properties in the green zones on the Port Hills and Banks Peninsula.

A summary of the DBH guidance for repairing or rebuilding houses following the earthquakes in TC1 and TC2 categories is available on www.dbh.govt.nz/canterbury-earthquake-residential-building.

NEWS

UPDATED GUIDANCE FOR THE REPAIR AND RECONSTRUCTION OF HOMES IN CANTERBURY PUBLISHED The Department of Building and Housing (DBH) has recently published updated guidance on the repair and reconstruction of houses in earthquake-affected areas of Canterbury.

The Revised guidance on repairing and rebuilding houses affected by the Canterbury earthquake sequence includes information for the repair and reconstruction of homes, including foundations, in green zone technical categories 1 and 2 (TC1 and TC2).

DBH Chief Executive Katrina Bach says the updated guidance will allow homeowners with damaged properties in the residential green zone to get on with the process of repairing or rebuilding their homes with greater confidence.

“The document forms part of the Government’s support for longterm recovery in Canterbury. It gives robust and well-balanced engineering solutions that will reduce the risk of injury to people and damage to homes in future earthquakes.”

The revised document reflects new scientific and geotechnical information and knowledge about the impact of earthquakes and the effects of liquefaction on residential dwellings.

It includes useful information on repairs to foundations and new foundations in TC1 and TC2, assessments of retaining walls for hillside properties, chimney repairs and repairs to house superstructures, pole frame houses and masonry walls.

The guidance also applies to repairs to homes in green zone technical category 3 (TC3) that do not involve foundations. Homes

in TC3 with foundation damage requiring structural repair will need site-specific geotechnical investigation and specific engineering foundation design. Further investigation is being undertaken to inform the development of suitable foundation solutions for TC3, with guidelines to be announced mid-April.

The DBH Revised guidance on repairing and rebuilding houses affected by the Canterbury earthquake sequence supersedes the guidance issued by the Department in December 2010 in response to the 4 September 2010 Canterbury earthquake. The revised guidance document can be downloaded from www.dbh.govt.nz/ guidance-on-repairs-after-earthquake.

When it comes to specifying concrete durability, waterproofing, and protection products, Xypex crystalline technology has no equivalent.

Xypex Admix C Series is accepted by Auckland City Environments as compliant with NZ Building Code Clauses B2 and E2, and by Good Environmental Choice Australia as compliant with GECA 08-2007 Environmentally Innovative Products Standard.

Call 07 575 5410 or visit: www.demden.co.nz

Concrete solutions

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NEWS

WORK TIME VARIATION FOR CONCRETE TRUCK DRIVERS Working in consultation with the New Zealand Ready Mixed Concrete Association (NZRMCA), the New Zealand Transport Agency (NZTA) has developed a generic work time variation for drivers of ready mix concrete trucks (agitator trucks), undertaking time critical delivery of ready mixed concrete. The variation allows drivers who are approved by the NZTA to take more frequent but shorter rest breaks during a working day. It does not extend the number of hours available for work during a working day.

The variation applies to the drivers of agitator trucks used in a ready mixed concrete operation only. It does not apply to drivers of other vehicles that support the production or placement of ready mix concrete, such as concrete pump trucks and trucks involved in the delivery of bulk cement or aggregate.

To summarise, under the variation, within any ‘cumulative work day’ a driver must be given the following rest breaks: • After a maximum of 4 hours work – 15 minutes: and • After a maximum 7 hours work and no more than 4 hours after the previous rest break – a further 15 minutes; and • After a maximum of 10 hours work and no more than 4 hours after the previous rest break - a further 15 minutes; and

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• After a maximum of 13 hours work – 10 hours Rest breaks are not to be taken in a moving vehicle associated with work, and during a rest break the driver must not be involved in any loading/cleaning/unloading process or other activity related to the task.

The variation is based on research completed by TERNZ which suggests that the current work time requirement for drivers to have a 30 minute rest break after 5½ hours work is impeding the economic productivity of the industry. The ready mixed concrete industry has put a conservative annual cost on this of $6 million. In addition, the research shows that short breaks, of 10 to 15 minutes, can be more beneficial for fatigue prevention than longer ones.

The variation is not available as of right; a written application has to be made to the NZTA. The NZTA will consider the application based on the information provided and other information it deems necessary to consider. This may include but is not limited to the safety performance of the operator employing the drivers.

For more information, and an application form, visit the NZRMCA website – www.nzrmca.org.nz

NEWS

“BUILD IT RIGHT” NEW ZEALAND The Department of Building and Housing (DBH) recently launched a two-year campaign “Build it Right” aimed at improving the quality of building in New Zealand and increasing the confidence of consumers.

The initiative will improve the productivity, efficiency and accountability of the building sector in New Zealand.

The first major change is the introduction of Restricted Building Work (RBW) on 1 March 2012. This means most residential building work requiring a building consent must be carried out by Licensed Building Practitioners (LBP).

DBH sector capability deputy chief executive Alison Geddes says the programme of work being introduced over the coming months will raise standards in the sector while doing away with unnecessary red tape.

“The first step has been to ensure we have enough LBPs assessed within a range of competencies relating to their licence class. Only they will be able to carry out RBW which is design and construction work critical to the integrity of a building,” Ms Geddes says.

“The Licensed Building Practitioner programme will give consumers additional comfort that they’re getting experienced building practitioners and ultimately a quality job,” she says.

Six licence classes relate to RBW - designers, carpenters, external plasterers, brick and block layers, foundation specialists and roofers. Registered architects, gas-fitters and plumbers, as well as chartered professional engineers, who are registered with their own professional authorities, are treated as being licensed.

Ms Geddes says New Zealand’s future economic prosperity depends upon a strong and successful building and construction industry.

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Concrete Solutions Our Rockcote’s MultiStop range of premium construction mortars are designed for ease of use as sandable or non sandable patch, repair, & finishing plasters to achieve the best result over concrete substrates.

“Over the past few years the Department and the industry have worked very hard to find initiatives that will allow the industry to flourish while offering consumers greater comfort and protection.

I think this programme of work reflects that.”

For a full list of the Licensed Building Practitioners go to www.dbh.govt.nz/lbp or for more information on your rights and obligations under the Building Act 2004 go to www.builditright.govt.nz

Always Start with a Better Finish

www.rockcote.co.nz 0800 50 70 40 volume 55 issue 3 MARCH 2012

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NEWS

CONFERENCE 2012 - HAMILTON Concrete Conference 2012 is to be held from 11-13 October at the spectacular Claudelands Conference and Exhibition Centre in Hamilton.

Conference Organising Committee Chairman Carl Ashby says the conference has not been to Hamilton before and the Claudelands Conference Centre is a top class facility that will give us the ability to run a full conference programme.

“With the publicity and reputation the city has been getting, thanks to the Hamilton V8s and other major events, the Organising Committee agreed it would be a great venue.”

Among Hamilton’s many attractions are golf courses, museums and the famous Hamilton gardens.

“There’s a great selection of fine dining establishments and, for those wanting to chance their arm, Skycity Casino,” says Carl. Meanwhile, NZCS Secretary Allan Bluett says the new Claudelands Conference Centre, which has been operating for about a year, is simply outstanding.

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“Each time New Zealand gets a new conference centre, it incorporates the latest in design and state-of-the-art technology.” Having not returned to his hometown for many years, Allan was impressed both by Hamilton and the Conference Centre, which is situated on 34ha of parkland an easy 10-minute walk from the city centre.

The country’s third largest conference centre and second largest exhibition centre, it can be configured to accommodate breakout workshops, and is ideal for the Concrete Conference.

You can learn more at http://claudelands.co.nz/19/ conference and visit Hamilton online at http://www. hamiltonwaikato.com The Concrete Conference Committee has tentatively confirmed the next two years’ conference destinations: Queenstown - 2013; Auckland - 2014.

NEWS

RATE YOUR HOME’S HEALTH AT HOMESTAR.ORG.NZ AND WIN CCANZ is proud to support Homestar™ and the Home Health Check Month. Homestar is an initiative designed to help New Zealander’s improve the health, warmth and comfort of their homes.

Take the free online test this month at homestar.org.nz and you could win a ‘Healthy Home Makeover’.

The Homestar test, together with your ‘Recommendations Report’ and help from a Homestar Professional can guide you through the design, construction and maintenance of a healthier, more naturally comfortable and eco-friendly home. *Competition closes April 15th 2012.

Further capability added to AQA The Aggregate and Quarry Association of New Zealand (AQA) is pleased to add a bright new name to its ranks.

Bill Bourke is now the Association’s Planning and Technical Adviser.

Bill has spent most of his working life in the steel industry with the last 10 years Bill Bourke concentrating on market development for the two main slag aggregates produced at New Zealand Steel.

During that time he has been a Director of the Australasian (Iron and Steel) Association (ASA), holding the position of Vice Chairman International.

His work has had a strong technical focus, and has included research on international testing requirements, the study and testing of local aggregates and comparing these to the properties of slag aggregates; health and safety; select committee submissions and customer relationship building.

In welcoming Bill to the ranks, AQA Chairman, Mike Lord said “Until now AQA Board members have taken on responsibility for technical and planning work, including administration and reports.

This has been a big ask for people who have senior day jobs.

Having a dedicated staff member will free up those members to concentrate more on AQA’s high level strategic focus”.

Bill, who took up his role in January, said “I believe I can make a significant contribution to the Association on behalf of its wider membership. I am well versed in the workings of an industry association, including strategic planning, budgeting, setting directions for technical research and environmental compliance.”

CONCRETE NEWS AS IT HAPPENS To keep up to date with all mainstream concrete media stories visit the CCANZ website (www.ccanz.org.nz) and check out the NEWS FEED box on the front page. To get ‘pushed’ the stories subscribe to the convenient RSS feed. Those readers using Microsoft Outlook 2007 or later can make use of the RSS aggregation capabilities of their favorite email programme.

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FREE NEW ZEALAND THERMAL MODELLING SOFTWARE

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CCANZ HAS TEAMED UP WITH GLOBAL LEADERS IN MEASURABLE SUSTAINABILITY, INTEGRATED ENVIRONMENTAL SOLUTIONS (IES), TO MAKE AVAILABLE A THERMAL MODELLING SOFTWARE TOOL SPECIFICALLY TAILORED FOR NEW ZEALAND CONDITIONS. VE-Ware, or Virtual Environment softWare, is a completely free whole-building annual energy and carbon usage tool, which can be accessed by the IES plug-ins to Google SketchUp™ (also free) or Autodesk® Revit®.

A proven mechanism for initial dynamic thermal modelling across the globe, VE-Ware has with the support of CCANZ, integrated local weather data and the NZ Building Code’s minimum R-Values to offer designers the ability to measure the potential benefits of thermal mass in new and existing buildings.

Concrete has the answers

Design, build and live with confidence

In line with the NZ Building Code’s Clause H1 Energy Efficiency’s calculation method, CCANZ CEO Rob Gaimster believes VEWare will become a key preliminary tool in reducing the carbon emissions of the built environment.

“It is imperative that we make buildings more energy efficient, as well as dramatically reduce operating overheads and CO2 emissions,” says Gaimster, “VE-Ware’s capacity to account for the benefits of concrete’s thermal mass in minimising ambient temperature swings and in turn improved energy efficiency is ideal as a first step in achieving these objectives.”

This is a view shared by Roger Cladingboel, IES Senior Business Development Manager. “For a long time designers have understood that thermal mass can reduce instantaneous heat transmission under dynamic conditions,” says Cladingboel, “with VE-Ware New Zealand now has an introductory simulation and modelling tool that clearly demonstrates how climate specific use of thermal mass can reduce heating and cooling bills as well as enhance local thermal comfort for occupants.”

With VE-Ware there are no reasons not to take the first steps in the drive for energy efficiency in buildings – you have the capability to understand “How well does my building perform?”

Along with the free to download VE-Ware, IES offer a complete range of Award winning powerful performance analysis tools that will aid professionals during a rigorous sustainable design process.

What does VE-Ware do?

• Suitable for all building types across national locations • Easy to use – produce results at the touch of a few buttons • Data entry and outputs are managed for you • Uses full technical capabilities of IES’s powerful dynamic thermal simulation • Based on real climate data and typical characteristics of buildings and systems

• Proven strength • Design versatility • Seismic performance • Low maintenance • Locally produced

• Affordable • Thermal mass • Fire resistance • Sound proofing • Long term durability

What does VE-Ware report on?

• • • •

Annual energy consumption Annual CO2 emissions New Zealand regulation compliance Climate Energy Metric that shows potential energy use derived from climate characteristics within a global context

To find out more about the benefits of Coming Home to Concrete visit:

www.cominghometoconcrete.co.nz

For more information on VE-Ware, and the complete suite of IES thermal modelling software, visit www.iesve.com Image: Cranko House by Kevin Hawkins Photography

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RESEARCH PREVIEW

THERMAL MASS RETROFIT OF NEW ZEALAND DWELLINGS Final year Victoria University of Wellington architecture student Jaden Cairncross and Senior Lecturer Morten Gjerde collaborated over the summer research period on a project looking at how thermal mass might be retrofitted into New Zealand homes and the effects this might have on energy use and thermal comfort.

The research aims to provide owners of lightweight timber-framed houses in New Zealand with examples of passive retrofit options and associated cost-benefit analyses.

Funding from CCANZ to conduct the research did not limit the testing of retrofit materials to concrete alone, with both water and phase change materials investigated in combination with concrete.

Current literature on the existing New Zealand housing stock; the existing energy use in New Zealand dwellings; how to improve New Zealand house conditions; passive solar design and material technologies provided the foundation and direction of the study.

Top level results indicated that while thermal mass was important to overall passive design, the role of insulation was also vital. Furthermore, it was demonstrated that although energy savings and comfort levels could be enhanced through purely passive retrofits, more significant improvements were achievable in combination with efficient active heating devices.

The full research findings will feature in the next issue of Concrete magazine.

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Optimising available solar energy is necessary for housing retrofits t reduce space heating ener increase internal temperatures. of passive solar design are 1) In add thermal mass 4) stop air l and 6) ventilate. Thermal mass effect on temperatures within bu thermal inertia of the room requ energy to significantly heat up when compared with light structures

to rgy and The six principles nsulate 2) Glaze 3) leakage 5) Shade s has a stabilising uildings as the high uires more heating p or cool down tweight

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Come Home to the Benefits of Concrete DESIGNED TO RAISE AWARENESS OF THE ADVANTAGES OF RESIDENTIAL CONCRETE CONSTRUCTION, FROM FLOOR SLABS THROUGH TO FULLY CONCRETE HOUSES, CCANZ HAS LAUNCHED THE COMING HOME TO CONCRETE INITIATIVE.

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Image: Signature Homes

CCANZ chief executive Rob Gaimster believes that New Zealand currently has a unique chance to fully explore the possibilities that can be achieved through the use of concrete and concrete products in our homes.

“As we move forward to tackle the challenges posed by the Canterbury rebuild as well as the predicted housing shortage in Auckland, the significant role concrete can play in providing comfortable, stylish and strong homes at affordable prices must be part of everyone’s thinking.

“The Coming Home to Concrete initiative illustrates how we have the opportunity to enhance our residential building stock by utilising the many benefits of concrete, and in turn ensure resilient and healthy homes for all New Zealanders.”

Central to the Coming Home to Concrete initiative is a short film fronted by Kevin Milne (available on DVD and online) that highlights the candid views of homeowners, architects and builders, during interviews structured around the attributes of concrete.

The recent amendments to the New Zealand Building Code in relation to (reinforced) concrete slab-on-ground are also summarised, with the intention of providing good practice guidance so that a quality slab is more easily achieved.

Image: Peter Fell Ltd

Along with the short-film, the initiative provides a range of readerfriendly print and web-based resources to help all those involved with residential construction make informed choices and optimise the potential of concrete and concrete products.

The campaign was made possible with the assistance of the Pacific Steel Group and the Aggregate and Quarry Association of New Zealand (AQA). A copy of the campaign leaflet is enclosed with this issue of Concrete magazine. For additional copies contact CCANZ admin@ccanz.org.nz To find out more about the benefits of Coming Home to Concrete visit www.cominghometoconcrete.co.nz

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RESIDENTIAL

CONCRETE SLABS

DO IT ONCE, DO IT RIGHT

Producing a quality concrete slab-onground is easy if some basic rules are followed. CCANZ has updated its Residential Concrete Slab-On-Ground Floors leaflet to reflect recent Building Code changes and assist builders to produce a quality slab.

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On 19 May 2011, the Department of Building and Housing (DBH) made changes to Acceptable Solution B1/AS1, which applied to the Canterbury earthquake region.

These changes took effect immediately. The definition of ‘good ground’ was changed to exclude ground subject to liquefaction and /or lateral spread, and stronger foundations were required for that region. These modifications to the referencing of NZS 3604:1999 have been carried forward to the referencing of NZS 3604:2011.

On 1 August 2011 the DBH extended the requirement for stronger foundations to the rest of New Zealand. It modified its referencing of NZS 3604:2011 to exclude unreinforced slabs.

RESIDENTIAL CONCRETE

SLAB-ON-GROUND FLOORS Producing a quality concrete slab on ground is easy if some basic rules are followed. This leaflet is intended to assist builders to produce a quality slab. The cost of rework is very high, so follow the suggestions in this leaflet to save time and money.

• All concrete floor slabs on ‘good ground’ are required to have reinforcing steel mesh • All perimeter foundations are required to be tied to the concrete slab with reinforcing steel The purpose of the mesh is to provide crack control, some flexural capacity to allow the slab to span local weak spots, and to provide some resistance against differential settlement by dowel action. Mesh will stop or limit the spread of a crack if it opens up.

The requirement to tie the perimeter foundation to the slab reinforcement is to provide a more robust composite foundation/floor, and limit movement and damage between these elements that might occur during earthquake shaking and subsequent ground settlement/displacement.

I N A S S O C I AT I O N W I T H

Accounting for these changes CCANZ, with the assistance of the Pacific Steel Group and the Aggregate and Quarry Association of New Zealand (AQA), has updated its Residential Concrete Slab-On-Ground Floors leaflet as part of the Coming Home to Concrete campaign. A copy is enclosed with this issue of Concrete magazine. For additional copies contact CCANZ - admin@ccanz.org.nz

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Firth’s RibRaft proves its worth in Christchurch quakes, AND… Firth Industries EQ RibRaft® flooring system has been designed to comply with the specifications of the Department of Building and Housing approved flooring solutions for the Christchurch rebuild.

The Firth RibRaft® system is an innovative method of concrete floor construction that is quick and efficient to lay and offers great strength and insulation benefits.

The system uses polystyrene pods, steel reinforcing rods, plastic spacers and RaftMix™ concrete. Each of the components fit simply together, dramatically reducing labour time and costs.

Firth’s Southern Regional Manager, Dominic Sutton has had his own experience of just how well the RibRaft® flooring system performed during the recent Canterbury earthquakes.

Dominic Sutton lives in Cashmere and built a granny flat five years ago for his mother-in-law on the same property as his weather board home.

The granny flat is a two story house constructed from Firth 20 series masonry blocks with a concrete mid floor and a RibRaft® foundation.

Cashmere granny flat sustained no structural damage, while…

Dominic Sutton’s home is an older weather board home, built in the late 1940s on a more traditional unreinforced concrete foundation - this did not stand up to the second big earthquake to hit the region but the granny flat did.

“Come February 22 our house exploded and the foundations are now broken and ruptured in multiple places,” says Sutton.

“Basically the house twisted and vibrated on itself and has now come off its foundation and we have not been able to live in it since then,” he says.

The Sutton’s home is in the white zone – which is an undecided hill zone. It is likely to require either significant repair or a total rebuild.

Amazingly the granny flat had no structural damage at all despite the fact that the two dwellings are immediately next door to each other and would have been hit by the same the shock wave.

“There is some minor cosmetic damage - a small amount of broken gib - but my mother-in-law is still living there,” says Sutton.

“The home acted like a bunker - the RibRaft® would have shaken but all the steel in it would have held everything tight,” he says.

“As the Rib Raft system floats on top of the ground when the ground starts shaking it can largely mitigate the effect of lateral spreading,” he says.

“It’s very strong compared to the old system, the current building code is far more earthquake specific than it was in 1948.”

…the unreinforced foundation of the adjacent property failed.

Firth was contacted after the first earthquake in September 2010 by research engineers who wanted feedback as to the performance and location of existing RibRaft® floors in the Christchurch and Kaiapoi regions.

The September 2010 and February 2011 quakes have caused significant ground failure around the region some homes have sunk by more than 200mm. Many of the worst affected areas have now been red zoned.

Sutton says he has spoken with many of the occupants of these homes with RibRaft® floors and they are very pleased with their purchasing decision to pay a bit more for this type of floor.

“The Department of Building and Housing’s foundation solutions guide suggests six or so ways of building foundations to cope with liquefiable soils and the EQ RibRaft® system will comply to their requirements,” says Sutton.

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®

flooring system at Christchurch Airport’s new regional lounge

The new Regional Lounge at Christchurch Airport features a Firth RibRaft® flooring system and was installed in the months during Canterbury’s recent major earthquakes.

The new Regional Lounge at Christchurch Airport, which has been project-managed by Octal Associates, is a joint venture between Air New Zealand and Christchurch International Airport (CIAL) and is one element of extensive work being carried out that includes a new check-in hall, baggage handling system, passenger lounges, improved passenger flows and enhanced retail and café offerings.

Situated to the east of the main terminal, the new building will service Air NZ turbo propeller aircraft and their passengers on flights predominantly throughout the South Island.

The new building includes a large hall area of approximately 1800 m2 featuring a striking black polished concrete floor with white quartz aggregate sprinkled throughout, that will serve as the main departure and arrivals hall for regional passengers.

“The project architects, Bligh Voller Nield, chose from a range of samples that mixed different shades of black and incorporated varying percentages of white quartz pebble,” says Dominic

Sutton, Regional Sales Manager (Southern) for Firth. “Control and repeatability of the mix was very important as multiple concrete pours were required by the program.”

“We worked very closely with Firth to get the test mixes just right,” says Des Allred, Site Manager for Mainzeal. “The team from Firth were very knowledgeable and helpful throughout the process and we are very happy with the result.”

The Firth RibRaft® floor system is suitable for both residential and light commercial applications and was specified by engineers Buller George Turkington. The RibRaft® system is an innovative method of concrete floor construction, offering an insulated floor with a quick, practical and efficient construction method providing high strength, durability and affordability. It was also chosen to ensure this glamorous floor will stand the test of time.

Dominic Sutton says, “The Firth RibRaft® floor system has stood up very well to recent seismic events and has now been added to the Department of Building and Housing’s foundation solutions guide for the Christchurch rebuild.”

“We have had all the six options listed in the guide costed and EQ RibRaft® is by far the most attractive option for home builders,” Sutton says.

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Concrete ENHANCES Historic Villa

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AN APPRECIATION AND UNDERSTANDING OF THE ATTRIBUTES OF CONCRETE ARE STRONG FEATURES OF A UNIQUE ALTERATION PROJECT NEARING

For Lloyd and the client, new concrete was the deliberate choice to match and complement the aesthetics of the historic concrete house.

The focus was on providing a sculptural mass accompaniment.

COMPLETION IN WESTMERE, CENTRAL AUCKLAND.

Passive Solar Benefits

Connecting a Victorian villa with its ancillary shed, both built around 1908 of aggregate and hydraulic lime/mix construction, the project creates new contemporary living and amenity space for a family, and includes a series of surrounding landscaped courtyards.

In linking the villa with the ancillary shed, the new two-storey build maximises the benefit of the sun and views into the various courtyards. “The passive solar design benefits of concrete were an obvious consideration throughout the planning phases,” says Lloyd. Both old and new walls are positioned to attract solar gain from morning sun.

With the single-storey villa and shed both having a Category B historic listing the new addition positioned between them required careful consideration to ensure the architectural heritage was most appropriately preserved and supported by council heritage architects.

Designer Steven Lloyd and client worked to retain the original house integrity and primary form. The villa is the most recent of a cluster of concrete villas produced by the Warnock family beginning around 1886.

“The concrete quality of the hundred-year-old villa is good,” says Lloyd. “The foundations are all secure, and the exterior surface is also of sound quality.”

The villa’s exterior walls are 10 inches thick, while the internal partition walls are 6 inches. In some instances the exterior walls became new internal walls. “To minimise contact with the existing house and ensure no new loads were applied to it, both floor and roof cantilever to them. All wall junctions with the original house are glazed.” This allows for an atmosphere of lightness that separates old and new mass, and at the same time provides for visual continuity of the original form.

During the winter, even before the addition was closed in, it was possible to sit in unglazed spaces and feel the heat radiate off the concrete elements.

To prevent over-heating, hinged totara screen louvres will span the North elevation. In cold weather these can be opened to allow solar penetration.

To give a cooling effect, a concrete fish pond is crossed to reach the back door, and the house opens to a new concrete swimming pool finished with cast coping blocks.

Other Concrete Features The new suspended concrete floor makes use of Stahlton rib, stressed with new timbers which slot into the cast wall below.

The floor’s under-side has been left exposed as the ceiling in the room below.

The concrete fireplace and cast hearth are integral with the walls. The fire’s shape and flue are specifically designed, and the concrete chimney sits easily alongside the historic villa.

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While pouring all concrete on site led to challenges in terms of managing formwork pressures and accommodating services, it enabled a unique aesthetic and a joint-free structure.

Construction Processes All concrete for the new build was poured on site. Challenges included co-ordinating services in walls and the slab, and taking great care with the formwork set out. “Pouring the new 190 mm walls involved substantial loads,” points out Lloyd. “The formwork was a major construction effort in itself. All joints and ties were detailed and the well-crafted assembly produced a great finish.”

The timber formwork was hand built using a meranti ply sheet producing a fine feathery grain finish on the concrete face.

The new concrete is a seamless mass as it was in the old villa.

“In-situ construction gives superior aesthetics, with more variation, and no joints,” says Lloyd. “In-situ also enabled us to accommodate changes in design as work progressed.”

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The courtside walls were stack cast on-site and lifted into place as panels straight off the form. They all went in over a short two day period.

The Future of Residential Concrete Before studying architecture Lloyd worked in a precast concrete factory making bridge beams and panels. This experience gave him an appreciation of what was achievable using concrete.

He sees residential concrete construction as offering unique aesthetic, thermal and structural appeal. “I love the variants in appearance that you can get with concrete, even within each pour you can get a difference in patina off the form. It’s alive,” says Lloyd.

“I find the design potential of concrete’s fluidity very appealing. There is a new interest in concrete houses with many people right now, and it’s curious to note that it was as attractive 100 years ago.”

Exterior images taken prior to installation of hinged totara screen louvres.

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RESIDENTIAL PRECAST CONCRETE

THE TIME IS NOW Innovative residential concrete construction is now at centre stage for a prominent Christchurch builder whose name is synonymous with home building in New Zealand.

Back in 1993 David Reid founded David Reid Homes (DRH) and successfully franchised the brand and systems to become the only residential building company operating nationally.

In 2004 Reid moved his family across the Tasman and over the next four years expanded the brand as a network franchised throughout all states of Australia. Meanwhile Reid’s New Zealand partners sold the local DRH business to a private equity company.

In 2008 Reid left the Australian DRH master agents to run the more than 20 franchisees, and moved his family back ‘home’ to Christchurch. He then formed Falcon Construction in response to the devastating earthquake of 2010 to pioneer what he calls a new generation of building companies.

Reid attracted headlines in 2011 when under the Falcon banner he gave away a concrete home to a Christchurch family that had lost theirs to the devastating earthquake.

Reid’s passion for concrete is a relatively recent development, stemming from his time in Australia when he struggled to produce

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the sheer number of homes required for the rapid expansion of mining towns. “We needed a design that was strong and quick,” says Reid, “and concrete soon became a great ally.”

Working with an Australian architect, Reid focused on modular precast concrete for residential construction. This system offered the added benefits of minimising subcontract work, simplifying transportation and optimising quality. It was the quality of the finished product that would entice miners to relocate their families closer to their place of work, as opposed to the “fly-in fly-out” custom that led to many social problems.

Evolution to concrete modules Reid at once saw the relevance of modular precast concrete methodology to the needs of quake-stricken Christchurch which was hungry for new construction. Soon his Falcon engineers and designers created an earthquake-resistant multiple-use concept.

Says Reid: “This CUBE system has great aesthetic lines. It’s based on an 8 m by 4 m module that can be stacked both horizontally and vertically, and it suits both residential and commercial applications.”

In its standard design, a CUBE building can go up to three levels.

Higher builds simply need specific engineering design.

The most remarkable feature of CUBE builds is their speed of construction – several times faster than lightweight frame alternatives. “Our first three-bedroom home was completed and landscaped in 14 days,” says Reid. “And our first commercial build was completed in 28 days.”

Not one of these CUBE buildings has moved despite experiencing the multiple aftershocks that have rattled Canterbury over the past 12-months. Further benefits include those common to residential concrete construction in general, such as high solar gain and thermal retention, low risk of dust mites and low exposure to allergens. An added bonus is that plasterboard is not required and neither is regular repair patching.

Ground preparation is dictated by soil condition and the GeoTech report. Options include poured strip footings, precast foundation pads and other standard types. Polystyrene insulation (50 mm) is laid. Then each concrete module is either poured onsite, or in the precast yard, as two walls with the floor between. In both cases the client can opt for lifting eyes and insert spacers cast-in every 4 m to facilitate later deconstruction and reconstruction on another site.

Adjacent floor modules are locked together (post-tensioned) by extendable Divirods. As the floor is suspended above ground, water-tightness is not an issue. Most CUBE clients choose not to sheet line, though there is a range of options resistant to earthquake movement.

Wiring, piping, waste holes, and in-floor heating are accommodated, with the pipes chased into the polystyrene to protect them during extreme weather.

The modular CUBE system can adapt to any floor plan and fit in with several other types of building element. Exterior finish options include plain concrete, cedar panels, or proprietary claddings.

All CUBE plans and drawings are subject to copyright and the system is unique to New Zealand.

Residential concrete at the Hive Clear evidence of the high-speed builds available with precast modular concrete comes from Falcon Construction’s participation with CUBE in the “Hive” Home Innovation Expo. Although opening to the public from Easter weekend, the CUBE exhibit did not start until early March.

Located at Canterbury Agricultural Park, less than 15 minutes from the Christchurch CBD, the Hive is billed as “a showcase of beautifully-designed sustainable permanent pre-engineered homes” open to public inspection free of charge.

Falcon and Allied Concrete have partnered to represent the prefabricated concrete sector with the “Rakaia” CUBE design aimed at meeting the needs of a typical Christchurch family. The floor will be poured onsite while all other elements will be made off site. Lifting eyes and thermal breaks will be built into the CUBE floor elements. Some of the floor areas will be polished.

“I think that in New Zealand residential construction, concrete has a huge future,” says Reid. “It was only after the February 22 quake that I saw prefabricated concrete as a viable, acceptable option for Christchurch. The quake has opened New Zealanders’ conservative minds to better design and construction techniques.

The time for concrete homes has come.”

For more information on Falcon Construction visit www.falconconstruction.co.nz Text by Tom Evison, Technical Press Service

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AWARD-WINNING DESIGNER ADVOCATES CONCRETE FOR SUSTAINABILITY

Upmarket residential housing designed and built to high sustainability standards is the specialty of Waiheke Island based company Lite-House. Established in 2008, Lite-House immediately began collecting national awards, including several House of the Year Gold Reserve honours. A key component to the company’s success was the astute use of concrete.

Managing director Bryce Ardern explains that Lite-House, sister company to Ardern Unique Design and Build, takes its name from a philosophy of leaving only the lightest footprint on the environment during both the construction stage and subsequent occupancy.

3. Respond to the local climate by careful design and siting

Since starting as a trade cadet, Ardern has spent 30 years in the building industry, mostly working with concrete, which is now his preferred material for structures. His company’s work is mainly in high-end and lifestyle residential assignments in the Auckland region but his designs have been applied as far south as Wanaka.

8. Demonstrate sustainable systems

Lite-House is a Registered Master Builder and Member of the Green Building Council. The company manages architectural design and management of expert subcontractors to achieve outcomes well beyond most government regulations and industry initiatives.

Bryce Ardern recognises a matrix of issues to meet market-driven demand. This matrix includes: personal responsibilities for green outcomes, awareness of global issues like climate change, national initiatives and incentives, and ecologically responsible architecture and construction without compromising aesthetics or quality.

Lite-House clients are informed of the company’s ten-point sustainability plan: 1. Minimise CO2 emissions by building with locally-sourced products 2. Minimise energy demands with super insulation and superefficient heating 26 concrete

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4. Minimise use of materials and other resources 5. Reduce and recycle building waste 6. Collect, conserve and recycle water 7. Select materials based on recycling analysis 9. Respect vernacular design and building 10. Create great architecture Concrete plays a key role in Lite-House achieving its sustainability objectives. Explains Ardern: “Concrete is ideal for durability, especially in a changeable coastal environment and where high strength is needed to withstand extreme winds. It is also lowmaintenance and yields passive solar gain year-round.

“We prefer exterior walls to be a concrete-XPS polystyreneconcrete sandwich with fibreglass connector pins distributed throughout the panel to stop delamination in the panels. No strapping and lining is needed and the concrete can remain exposed if that is the desired look. Our floor slabs are poured over ribraft forms and are sometimes left exposed”.

Ardern describes construction of a recently completed LiteHouse home on Waiheke Island. “To meet Geo Technical recommendations, we began by pouring short-bore concrete piles which extend 4 m into the ground. Next we poured header beams, then stood the concrete sandwich wall panels which were

Complete large sandwich panels, including wall-lintel-wall as above, were cast as one in a Silverdale factory and shipped to site on Waiheke Island. Note the cast horizontal rebate which is repeated on internal wall faces.

propped and levelled. All wires and pipes were allowed for with conduits cast into the wall panels connected to, and reticulated with, conduits laid directly on the earth floor. With these in place the Bentonite DPC membrane was placed to allow ribraft floor pods and the concrete floor to be poured”.

Workmen took extreme care to protect underfloor services and the internal and external faces of the sandwich panels. The concrete sandwich panels are founded below the floor slab, providing a thermal break at the perimeter of all external walls, ensuring no heat is lost in these vulnerable areas.

The home makes very honest use of the structural materials: everything is on show. Waiheke Rock and precast concrete walls with ply ceiling panels flow seamlessly from outside to inside.

The structure is engineer designed to withstand earthquakes.

Floor slabs are well connected to the walls. “There is always an element of over design to give the designer, builder, engineer and client peace of mind that these homes perform well in any event,“ says Ardern.

Lite-House thermal insulation is well above and typically double Building Code requirements. For example the sandwich walls have R 3.5, the roof is R 5.0, and the ribraft floor is R 3.0. Double glazing low-E glass ensures limited heat loss or gain through the aluminium joinery.

All Lite-House structural concrete is 40 MPa with additives and a similar mix is used to produce concrete bench tops and vanity tops when required.

Looking at New Zealand residential architecture, Ardern sees sustainability and innovation facing the dual roadblocks of cost and leaky homes. However, he’s pleased to see that more people are using concrete these days, mainly at the upmarket end.

“Compared to leading countries in Europe, New Zealand is well behind with central and local government incentives for sustainable design,” says Ardern. “While our government stays very pre-occupied with the Canterbury earthquakes and the world wide economic crisis I see little chance of change.”

Ardern is very enthusiastic about concrete. “It’s a bright star in the future development of New Zealand residential construction”, he says. “We’re now looking at modular housing using prefabricated sandwich panels, but much education is needed. “When we talk to clients about the benefits of concrete construction there’s surprise when they learn how well it performs.”

Ardern’s main message for people seeking Best Practice in residential construction: “First, the design must be right as regards the environment, siting for topography, aspect and predominate weather patterns, and ensuring the layout meets the clients brief. Then it’s a matter of getting the materials specification right – and concrete is prime.”

For more information on Lite-House visit www.lite-house.co.nz Text by Tom Evison, Technical Press Service. Images: Denis La Touche

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LIGHTWEIGHT PRECAST CONCRETE FOR MAJOR AUCKLAND DEVELOPMENT Situated in Flat Bush, one of Manukau’s newest suburbs, the Lily Garden residential development is aiming to provide 67 high quality properties set amongst attractively landscaped surroundings. Only a few minutes’ drive from schools, restaurants, a supermarket, golf course and the proposed Flat Bush Town Centre, Lily Garden is emerging as a much sought-after residential development, key to which are the benefits of residential concrete construction.

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The first four 2-storey houses at Lily Garden were constructed using Litecrete, a lightweight precast concrete system. Local architectural design house Mox Design created the unique four or five bedroom houses. Several internal structural Litecrete walls allow for the timber framed partition walls to be later positioned to accommodate individual owner preference.

The first 260 m2 house was installed in just over a day. This involved 29 Litecrete panels, timber mid floor and roof assemblies.

The roof and mid-floor sections were built onsite, adjacent to the floor slab, and craned on to the building after the Litecrete panels were installed.

Exterior faces of the external precast panels were painted, and windows were installed, prior to the panels being delivered to site.

Remaining work on the precast walls involved only internal decoration.

The second, third and fourth houses were each installed in under nine hours.

Key benefits of repetitive precast concrete manufacture were the ability to reuse existing architectural and structural designs and shop drawings and take advantage of increased factory efficiencies. There are also cost savings arising from the use of “Multiproof” building consents requiring minimal site visits from the building certifier.

Litecrete NZ is a wholly-owned subsidiary of Wilco Precast, which has been manufacturing precast concrete for nearly 50 years, and operates out of a state-of-the-art production facility in Papakura.

The precise mix formulation and production system for the lightweight panels is the result of many years of development.

Says marketing manager Philip Archer: “Our drafting department can convert almost any architectural design to suit our production process. Many of our skilled factory staff; wood workers, steel fabricators and concrete placers; have been with the company for more than 10 years and there is a strong emphasis on quality assurance.”

Litecrete is named for the lighter pumice that replaces the heavy coarse aggregate in standard precast panels. Pumice reduces dry panel weight by 50% while significantly enhancing acoustic and heat insulation values. Less weight means more volume can be transported on each truck, reducing the number of trips and consequently CO2 emissions.

According to Archer, the Romans built the Pantheon’s dome with a similar pumice concrete mix, which has endured for over 2000 years. “For residential and commercial construction Litecrete offers rapid installation through large panel sizes, has a four hour fire resistance rating and is rot, mould and moisture proof. I’m absolutely confident we’ll never get ‘leaky home syndrome’ from a house built with Litecrete.”

The load bearing panels come in sizes up to 7 m x 3.5 m, with window and door openings cast in. Panels at 220 mm thick comply with Building Code H1 Energy Efficiency rating, and their acoustic values enhance peace and quiet between rooms, floor levels and the external environment.

Onsite installation is very straightforward. Panels lifted off the truck are lowered over starter bars previously cast into the floor slab. The starters are later locked in to the panels using epoxy grout. Each panel is temporarily propped, and weld plates are connected if specified. Panel installation is unaffected by adverse weather.

Interior and exterior faces can be painted or finished with fine or accented plaster. As Litecrete walls breathe, vapourpermeable plaster and paint systems are recommended, allowing condensation to escape outdoors. Deep reveals are provided around windows and doors.

By taking advantage of concrete’s thermal mass, in combination with an appropriate level of roof insulation and double glazing, the Litecrete walls regulate internal temperatures to provide a healthy and energy efficient living environment throughout the year.

The current focus on seismic durability also favours Litecrete. The panels have both steel and polypropylene fibre reinforcing to give a uniquely high strength-to-weight ratio while greatly reducing the dead load transmitted to foundations and superstructure members. Litecrete comes with a 50-year transferable structural warranty.

“The bottom line for Litecrete, as demonstrated at the Lily Garden residential development,” says Archer, “is dramatically reduced construction times, reduced energy costs, reduced long-term maintenance costs and a healthy living environment.”

For more information on Litecrete visit www.litecretesystems.co.nz

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australia

GRAND DESIGN FOR SMALL HOUSE An ultra-compact home tucked into a tiny laneway in Sydney’s inner city offers a glimpse of an urban living future driven by practicality and design.

The aptly named ‘Small House’ boldly reconciles some of the challenges of inner city living – such as soaring property prices, lack of privacy and lack of space – with its many lifestyle benefits, including proximity to work, shops and restaurants.

In a tiny, garage-sized 7 m x 6 m site in Sydney’s Surry Hills, surrounded by large commercial buildings, the ‘Small House’ is zoned vertically, rather than horizontally.

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“We used a number of design devices to make micro spaces more liveable,” explains owner and architect Domenic Alvaro, design principal of Sydney firm, Woods Bagot. “The design eliminates rooms, assigns multiple uses to single spaces, has no corridors or doors and diversifies the use of each floor. It also offers the flexibility of adding spaces in the future.”

Vertical zones begin at the ground with utility/store/bicycle/ parking, moving up to sleeping/bathing, followed with a living area, then an eating/food preparation/entertainment zone. The structure is topped with a working roof garden.

Zones are connected via a stair void which relays light throughout and acts as a thermal stack, drawing air out through each level via the roof-top glazing, maximising cross-ventilation. Large sliding windows flood the interior with daylight and frame city views. A services riser connecting each level enables the reticulation of all services and additional storage.

Critical to the success of the project was the collaboration between the architect and builder, Baseline Constructions, and the extensive use of precast concrete, which was supplied by Hanson Precast.

The precast option offered not only the solidity to ensure privacy in this built-out neighbourhood, but a high quality, exemplar finish that eliminated the need for paint and other decorative finishes.

It also enabled the most challenging part of the project – its miniscule site – to be overcome.

“The builder brought an innovative approach to such a difficult site by thoroughly pre-planning all the necessary details for offsite production and minimising disturbance to the surrounding neighbourhood by delivering on a speedy timeline,” says Domenic Alvaro.

The precast components comprised 318 m2 of 175 mm thick loadbearing wall panels in Class 2 off-form and 138 m2 of 150 mm thick hollowcore floor planks, which were erected in just four days.

“The real issue with the construction was craneage,” says Chris Parsons, Manager of Hanson Precast. “Essentially, until we could determine the logistics, there was no guarantee the job could go ahead. Not only did we have to accommodate the site size, narrow streets and existing buildings, there were real concerns that the position of a light pole on the street would block our only access.”

In the end, a 55 tonne, all terrain mobile crane was used, with the crane jib position and slew of the counterweight plotted to the millimetre to miss the neighbouring buildings.

“With most projects, a visual inspection and someone pacing out some dimensions is all that is required. But the decision in this case was made on the basis of an extraordinarily small 50mm tolerance: the ultimate tight site” explains Chris Parsons.

The access problem was ultimately resolved with a practical solution: placing one crane outrigger through the garage opening in the wall panel on the ground floor – a solution that enabled the swift and successful erection of the precast elements.

‘Small House’ and the story of its design and construction is featured in the Australian version of the popular architectural television series, ‘Grand Designs’.

Architect: Domenic Alvaro Builder: Baseline Constructions Precast manufacturer: Hanson Precast Article reproduced from National Precaster #59, with kind permission of the National Precast Concrete Association of Australia (NPCAA)

Small House wins World Best House at World Architecture Festival Awards 2011 ‘Project demonstrated commitment and excellence on many levels’ Small House in Sydney’s Surry Hills, designed by Domenic Alvaro, has won the ‘World’s Best House’ award at the prestigious World Architecture Festival (WAF) Awards 2011. Critical to the success of the project was the collaboration between the architect and builder, Baseline Constructions, and the extensive use of precast concrete, which was supplied by Hanson Precast.

The jury commended the project, saying: “Built on a difficult laneway site in Sydney, more than any other contender this project demonstrated commitment and excellence on many levels. From the concept right through to execution, employing construction techniques more typically used on large scale commercial projects in response to physical and budget constraints.”

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CHOOSING TO LIVE IN A HIGH FIRE DANGER AREA IS ONE THING, BUT WANTING TO MAKE IT ENERGY EFFICIENT ON A WEST FACING SLOPE ADDED MORE CHALLENGES WHEN SARAH BACHMANN EMBARKED ON HER OWN BUILDING PROJECT. 32 concrete

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A ustralia

Energy efficiency and fire safety – is it possible?

Around two years ago, my partner and I made the decision to move back to Adelaide after 16 years in Sydney. Deciding to resettle in the Adelaide Hills suburb of Belair, we looked to buy a house, but were adamant that it must be energy efficient, durable and safe from bushfire. There weren’t any, so we decided to build.

The block we decided on has magnificent views over Glenelg and the Southern Adelaide Coast and fronts right on to a band of bush that forms part of the Mt Lofty Ranges and marks where the Adelaide Hills begin.

We thoroughly investigated the choice of construction options.

Even though I have a natural bias towards precast concrete, I kept an open mind and we considered many and varied alternatives, from rendered block to various forms of insulated concrete forms. We were seeking to tick all our boxes of energy efficiency, durability and fire resistance.

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Every time we reviewed an product, we kept coming back to one of the newer products which are being offered by the precast industry in Australia – precast sandwich panels.

Precast sandwich panels are comprised of a thinner precast outside skin (typically 70 to 80 mm) and a thinker precast structural inside section (typically 100 mm), which are held together by nonthermally-conductive ties and with an insulation layer in between.

The system allows the outside skin to expand and contract with fluctuations in temperature, without compromising the structural effectiveness of the building. It also maximises thermal mass benefits by having the large volume of unlined concrete on the inside of the building. Because of the high quality of the precast finish, all that is required on both surfaces is staining or painting.

Double glazed windows have also been utilised and mechanical shading both inside and out, which will allow shading of the western glass from afternoon sun. Eaves on the north face prevent ingress of summer sun but allow entry of the lower winter sun.

There are minimal windows on the south side of the house.

We have also staggered the living area on the western face to provide sun access from the north. During the day, the heat from the sun passes through the windows and is absorbed into the thermal mass interior walls and into the thermal mass slab-onground (most of which will be tiled). At night, that same heat is slowly released back into the interior of the building. When placed on the inside, concrete has the ability to absorb and release heat slowly, allowing the inside of the building to remain at a fairly constant temperature all year round.

Precast concrete sandwich panels, together with CSIRO firetested and rated double glazed windows and a very well insulated Colorbond roof will give us a highly energy efficient, fire resistant and durable home. To further reduce the home’s use of resources, photovoltaic solar panels will be used. These are expected to generate sufficient electricity for the dwelling’s use plus return power to the grid.

Two water collection tanks (with a capacity of 112,000 litres) will collect rainwater and stormwater to supply the majority of water needs. Greywater will also be treated and re-used on the droughttolerant permaculture-style garden.

A solar hot water system will be installed and an energy efficient air-conditioning system will be used, while in-slab hydronic floor heating will further enhance thermal mass benefits of the floor.

And from a fire safety perspective, gutter guards and in-ground and roof sprinklers will be installed. All light fittings and appliances will also be energy efficient.

Sarah Bachmann is executive officer of the National Precast Concrete Association Australia (NPCAA). For more information about this project go to www.hillsideproject.net Article reproduced from BPN, March 2010 Volume 46 Number 2 with kind permission of the National Precast Concrete Association of Australia (NPCAA)

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germany

CLASSIC

concrete MODERNITY AN INCREASINGLY POPULAR APPROACH TO PROPERTY DEVELOPMENT IN BERLIN HAS SEEN A GROUP OF LIKE-MINDED FAMILIES, IN PARTNERSHIP WITH WELL-RESPECTED ARCHITECT AND PROJECT MANAGEMENT COMPANIES, TURN TO CONCRETE TO HELP REALISE THEIR VISION FOR AN AFFORDABLE AND CONTEMPORARY RESIDENTIAL COMPLEX IN THE HEART OF THE CITY.

PROJECT DEVELOPMENT Four years ago, on behalf of a private group of property owners, Zanderroth Architekten acquired a south-facing site close to the path of the now demolished Berlin Wall. Without third party investors, the eleven couples and families that comprise the group set about creating a template for urban living that met their desire to enjoy all the conveniences of the central city without compromising adequate living space.

Zanderroth Architekten has experience with building projects involving a group of ‘unit’ owners who ultimately wish to live in the development themselves. For such projects Zanderroth reserve the right to determine their structure and architectural language, and along with their allied project managers, achieve rapid progress that is not hindered by an entirely commercial group dynamic.

ARCHITECTURAL VISION There were many reasons behind selecting concrete as the primary construction material. “For us it was about the rehabilitation of a building material”, says Sascha Zander of Zanderroth, “Concrete has gained a bad reputation in nearby Wedding due to the [Berlin] wall and the brutal 1960’s buildings. We wanted to show the possibilities hidden in this modern building material.”

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The key characteristic of the building is a continuous, winding element - a band of reinforced concrete that runs around the exterior of the building, connecting it to the ground, defining each level, and providing closure. The plasticity of the band provides both an exterior frame for each apartment as well as a sense of fluidity at the street corner.

Various openings emerge between the levels of the reinforced concrete band in the form of projections and recesses. At certain levels the building’s facade is open along its entire width and height to transform the living areas into room size loggias. Where the facade recesses, it creates terraces, for which the band serves as a protective parapet.

CONCRETE CONSTRUCTION The concrete renaissance for residential construction in German cities is being driven in part by the capability to achieve a bespoke surface finish.

In this instance, the concrete was cast on-site, meaning that clear communication between all members of the construction team was needed to achieve the desired finish on the continuous facade band.

germany

Concrete has the answers Design, build and live with confidence

The main issues to be addressed were the quality of execution, texture, appropriate formwork and anchoring solutions. Easycrete SF was selected as being the most appropriate mix for ease of placement and setting, while also allowing formwork stripping that best preserved the delicate bamboo surface pattern, edges and corners.

The formwork was then erected adjacent to the structural element, with the concrete placed in the void between. Due to the pressures involved, concrete placement required a C35/45 GK8 F6, similar to that used in underwater construction.

The decision was made not to use mould release agents, but rather pre-wet the Reckli formliners. Several 4 m2 reference panels were created prior to construction in order to determine how the desired result could best be achieved.

The production method was then adopted onsite to realise the parapet elements.

The resulting surface finish has been deemed a huge success by all parties, creating a new brightness that lightens up the historically burdened area around the path of the former Berlin Wall.

• Proven strength • Design versatility • Seismic performance • Low maintenance • Locally produced

• Affordable • Thermal mass • Fire resistance • Sound proofing • Long term durability

To find out more about the benefits of Coming Home to Concrete and request an information pack visit: www.cominghometoconcrete.co.nz

Article reproduced with kind permission of opusC Concrete Architecture & Design www.opusc.com

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switzerland

UNIQUE APARTMENT LIVING with exterior rooms

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SWISS ARCHITECTS PATRICK GMÜR AND JAKOB STEIB HAVE DEMONSTRATED THAT EVEN IN LARGE EUROPEAN CITIES, WHERE LAND FOR RESIDENTIAL DEVELOPMENT IS SCARCE, INTUITIVE DESIGN COMBINED WITH THE VERSATILITY OF CONCRETE CAN ENABLE MODERN, MEDIUM DENSITY, RESIDENTIAL COMPLEXES WHERE EVERYONE CAN ENJOY THEIR OWN OUTSIDE LIVING SPACE WITHOUT CASTING A SHADOW OVER THEIR NEIGHBOUR. Zurich has a problem. It is stunningly attractive – so much so that it is bursting at the seams. Available plots of land for building are rare, while renting is increasingly becoming unaffordable.

So dire is the situation that the City has initiated a campaign that calls for ‘10,000 flats in 10 years’. To assist with meeting their own objective the City has reclassified certain areas to allow for a denser population, and also sold plots for development. The hillside section on Paul Clairmont Strasse in the south-west of the city, on which now stands the Gmür and Steib designed property, is one such example.

The architectural partnership has created an elongated, four to eight-storey residential block that reflects the terrain as well as the differing scales of the built surroundings. The offset, room-sized balconies, with their solid concrete balustrades, form an even geometrical pattern that appears to dissolve as it approaches the street on the building’s south side. This provides each apartment with a sheltered 24 m2 ‘exterior room’ of almost equal size to a typical terraced house garden. It is a real luxury in the city: a personal place in the sun.

On the north side, the sculptural building looks quite different, with bands of windows that emphasise its length and awaken associations with modernism. The sleek, homogeneous white concrete surface acts as a tie that restrains the stepped street frontage.

The building is accessed via two entrances on the north side, which are connected within by a long corridor. Situated along this internal thoroughfare are the service areas, along with smaller units, which can be used as flats, studios or offices. Beneath each of the building’s five staircases, which provide access to two flats on each level, is storage space.

The individual rooms are arranged on the north side, in three or four room configurations. In order to make space for this, the architects pushed the two middle rooms towards the outside through the line of the façade. The living rooms with open kitchenettes, along with the balconies, are situated on the south façade.

The completely re-interpreted balconies offer residents a versatile extra room. The high solid concrete balustrade, in which a cutout forms a window on the surroundings, combines with the protruding balconies adjacent and above to create a sheltered, two-storey private patio, while at the same time allowing daylight to penetrate deep into the apartments.

Through a simple design innovation, and the flexibility of concrete, architects Gmür and Steib have, in the form of a balcony, used a traditional building element to address the age old need for outside private space – but they have done so to unique and intriguing effect.

Article reproduced with kind permission of opusC Concrete Architecture & Design www.opusc.com

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united arab emirates

Delivering five precast

Governmental authorities in the United Arab Emirates are developing vast housing communities in the Emirate of Abu Dhabi, to cater for the needs of the national population. The main requirements for these projects are speed of execution, quality, durability and reliability. Precast manufacturing is an optimal solution. One recent contract saw the construction of five precast villas per day as part of a development of more than 2000 such buildings.

Precast wall panels storage

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united arab emirates

precast villas per day Daniele Pfeffer Seraphim, Gulf Precast Concrete Company, Abu Dhabi, UAE

Completed villa with boundary wall and GRC decorative elements

In January 2010, Gulf Precast was selected as a precast contractor for 2069 villas of various designs in the Al Falah area, Emirate of Abu Dhabi. The main pre-requisite was to hand over five villas per day, with heavy penalties in case of delay.

The scope of work included precast wall panels, hollowcore slabs and glass-fibre-reinforced concrete (GRC) decorative elements.

Gulf Precast was able to cater for the needs of the Al Barari development due to its seven production facilities, technical design teams and its product range.

An additional challenge was soon added to the original scope of work – the production and erection of more than 220 km of surrounding boundary walls as well as the superstructure works for numerous electrical substations within the development.

Project description Although precast manufacturing is the best option for such a large development both from economy of scale and time frame perspectives, the project is far from being entirely repetitive in its nature. It includes three-, four- and five-bedroom villas.

For each villa size there are three different styles and each style includes a mirrored option. Thus there are 18 different types of villas in the development, with different types of precast elements per villa varying between 40 and 100, excluding the hollowcore slabs and the GRC decorative elements.

The project is divided into three phases, with Phase I comprising 320 villas to be delivered by December 2010, Phase II having 739 villas to be completed by September 2011 and the remaining 1010 villas to be handed over by June 2012.

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united arab emirates

Site erection

Storage area in the hollowcore factory

Design specifics

the stringent time constraint of the project, the factories started production as soon as the approval of any element was received, even if the full set for a villa or a floor was not yet available.

Most of the precast projects in the UAE are pre-engineered before production. Once the concept design and structural integrity of the 18 types of villas was approved by the client, the engineering team proceeded to detail each of the 3085 different types of elements, including all connection details and electromechanical inserts.

Approved drawings were sent in a phased manner to the factory floor over several months, to allow production to start while the engineering team continued to co-ordinate with the consultant, MEP subcontractor and architect.

The engineering department soon identified that the boundary wall design could benefit from substantial cost saving by modifying the column footings from eccentric as originally intended, to concentric. However, this design modification would require Governmental approval.

Although the approval would take time and the tight production schedule did not allow waiting for it, Gulf Precast decided to quote based on concentric footing to secure the boundary wall variation works. One month after the start of the eccentric footing production, the concentric footing option was approved and a second set of drawings was implemented for further production.

Production challenges The original plan was to start producing one month in advance and build up a stock of villas in the factories in order to deliver according to site requirements.

However, because of the high number of different elements, the cumbersome process of obtaining approvals on all of them and

Development panoramic view.

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To minimise the delivery logistic difficulties, it was decided that one factory would specialise in the wall panel production of the five-bedroom villas, a second one in the four-bedroom and a third one in the three-bedroom villas. Each of these three plants took over the production of six different types of villas, and thus a high number of different types of wall panels. The remaining factories specialised in hollowcore slab production, GRC production and panels for the boundary wall. Thus all Gulf Precast’s production plants were handling different parts of the project.

A major challenge for the production of wall panels was to determine the optimal production cycle. Although the three factories involved are able to produce more than one villa per day, they cannot produce all six different types at the same time.

Switching from one type of villa to another requires mould changes that necessitate up to five days of modifications, during which no casting can take place. It would therefore have been optimal, from a production point of view, to complete all villas of a given type before starting the production of the next type. However, this is not possible, as the site has to be supplied in zones in which all 18 types of villas are mixed. Thus, the cycle of mould changes had to be studied carefully in order to minimise the number of changes, while still meeting the requirements of site erection.

In addition, a semi-mobile production plant was set up directly on-site, to manufacture columns and footings for the boundary wall, which are cast as one element, thus offering a significant increase in production and storage capacity. The plant is fitted with equipment to monitor and control the product quality.

united arab emirates

On-site semi-mobile factory

Development overview

An original plan was devised in order to store the elements on the factory grounds according to their site delivery sequence.

contractors. One of the current main challenges faced on-site is the coordination and interfacing with these other contractors.

However, as partial drawing approvals were received, production for the approved elements needed to start right away due to the stringent time line. This led to the number of elements cast for those drawings received first exceeding those received later.

At the onset of the project the carefully planned storage system had to be discarded in order to store a large number of panels that were not part of a full set, creating storage engorgements, additional loading time and immobilisation of high-cost inventory. Over time, double-casting of the elements lagged behind enabling Gulf Precast to catch-up with full sets of deliverable elements.

On-site erection challenges On-site the erection team, subject to a stringent time schedule, was sometimes obliged to receive partial floors of panels, knowing that the few remaining ones would be delivered a few days later.

This of course entailed additional costs of double handling and crane usage. This condition persisted throughout Phase 1, with 320 villas to be delivered by December 2010.

By the time Phase 2 started, in January 2011, the production had caught up with elements whose design had been received late, and full floors were routinely delivered.

The current objective for Gulf Precast erection team is to achieve erection directly from the trailer, avoid any site storage and maximise use of the cranes.

Due to the stringent time schedule of this project, the developer has decided that the infrastructure contractor responsible for all deep services and roads shall work in parallel with villa

Lessons learnt One of the key lessons learnt on this specific project is the critical importance of regular planning meetings between the factory operations team, the site erection team, the transport team and of course the planning department. Through weekly planning meetings, during which constraints faced are discussed and understood, the delivery plan for the next week is elaborated, taking into consideration the constraints of each process.

As developments of this size are not frequent, it is of critical importance to gather the expertise, knowledge and learning to be able to reuse them in forthcoming projects, even if they occur after a significant time lag.

Formal documentation of that additional knowledge is therefore critical for future references. Gulf Precast implemented quarterly inter-disciplinary meetings to discuss and document the key lessons learnt.

Although the size and stringent time schedule of the development triggered a number of difficulties, it should be noted that these were all overcome, sometimes at a cost, and that the project is ahead of schedule and the target of handing over an average of five villas per day is being successfully achieved. This demonstrates that precast was the right solution for the project, provided that the precast manufacturer holds both sufficient production capability and expertise.

Article reproduced from Concrete Engineering International July 2011 with kind permission of the UK Concrete Society.

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Concrete Benchtops For a truly creative surface finish Concrete is one of the most extensively used building materials in the world. Applauded for its versatility, it is no surprise that concrete has become part of our everyday lives, providing a backdrop to our outdoor living as well as forming the basis of many of our home essentials.

The use of concrete within kitchens is gaining in popularity. In particular, advances in the design and fabrication of concrete benchtops over recent years have led to a new trend in using concrete for kitchen workspaces.

Concrete benchtops comprise cement, aggregates, water and a combination of admixtures. Other additives that can be used include fibre reinforcement, silica fume pozzolan and acrylic.

Solid, practical and durable, concrete benchtops provide an economical as well as attractive workspace alternative to more traditional materials such as marble, granite and plastic laminate.

The flexibility of concrete lends itself well to incorporating a range of different effects and surface finishes: raw or highly polished, natural greys tinted or integrally coloured, surfaces patterned or stamped, acid-etched or crazed sand/glass blasted or with exposed polished aggregates - the list is endless. There are also a wide range of pigments, stains and aggregate colours that can be used to create unique and individual concrete benchtops.

The beauty of concrete also means that it can easily be formed to integrate additional practical features such as sinks, draining boards, backsplashes and wet walls.

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Images: Custom Concrete – www.customconcrete.co.nz

As a general rule of thumb, benchtops are around 50 mm thick. A 50 mm thick concrete slab weighs approximately 120 Kg/m2.

Therefore, floors and standard cabinetry should be checked for structural soundness before the benchtop is designed.

Benchtops are either precast in a factory, where conditions are easily controlled and where the benchtop is cured and sealed, or built on site.

Precasting is a popular method since it can help to speed up the installation of a new kitchen or bathroom and limits mess - once in place precast benchtops only require a light sanding, polishing or coating with sealers.

By contrast, benchtops built on site can readily be formed to specific requirements such as radius edges or curved corners. However, this method can prove time-consuming since the concrete needs to be hand-trowelled then left to harden prior to cutting, polishing and coating with sealers.

Sometimes, concrete benchtops can develop hairline cracks as a result of the natural shrinkage of concrete. These hairline cracks tend to be nonstructural and will not affect the durability of the concrete.

To minimize the risks of this happening, reinforcement materials such as steel, wire mesh, fibreglass and/or fibres can be used.

Concrete benchtops should always be cured and then sealed. If left in its natural, unsealed state, the surface will stain and scratch. It should be noted, however, that staining can occur if the sealant is damaged, say from a hot pan.

There are two types of sealants that can be used, non-absorbing sealers and penetrating sealers. Non absorbing sealers, for example epoxies, urethanes, lacquer and acrylicbased products, provide the concrete with a protective skin and act as an effective barrier to stains but they can look artificial. Penetrating sealers, whether water, silicone or solvent based, give an enhancing low sheen finish but usually require several coats to improve stain resistance.

Cleaning and caring for concrete benchtops is straightforward. Spillages should be wiped up as soon as they occur and only a mild, non-abrasive, non-ammoniated cleaner should be used - although mild soap and water is adequate.

If, over time, the concrete surface does become stained and scratched, then re-polishing is always an option - particularly as this will restore the benchtop to its original finished condition.

A SOLID & STYLISH SURFACE The books summarised BELOW are an ideal way to find out more about enhancing your home interior through durable and aesthetically pleasing concrete work surfaces.

CAST-IN-PLACE CONCRETE COUNTERTOPS

BY TOM RALSTON Concrete countertops are on the cutting edge of today’s interior design and outdoor kitchen trends. Kitchen designers, contractors, architects, and homeowners alike can use this book to learn the detailed process of creating concrete countertops. Here Ralston shows how to plan, execute, and complete a concrete countertop cast-inplace for ease and convenience. This book is for anyone interested in concrete countertop fabrication.

CONCRETE COUNTERTOPS

BY FU-TUNG CHENG At last, a complete start-to-finish book on creating countertops from the most versatile material available.

One of the most widely used and durable construction materials in the world, concrete can be formed into both simple and complex shapes, based on the needs and design expectations of the homeowner. In designer Fu-tung Cheng’s hands, concrete becomes a wondrous medium for creating one-of-a-kind countertops for your kitchen and bathroom.

MAKING CONCRETE COUNTERTOPS

BY BUDDY RHODES This invaluable manual will guide craftsmen through each step of creating a cast concrete countertop, from the careful process of measuring for a template, to building a mould, through casting and installation. With more than 30 years of experience in concrete art and fabrication, artist Buddy Rhodes shares his skills and experience in this book. He details techniques for hand-trowelled and polished countertop surfaces.

MAKING CONCRETE COUNTERTOPS WITH BUDDY RHODES: ADVANCED TECHNIQUES

BY BUDDY RHODES The companion volume to Making Concrete Countertops

by Buddy Rhodes, this book details the art and craft of creating vertical concrete applications as well as integral sink and drainboard elements and curved-edge counters, for advanced users of the medium. An invaluable manual for contractors, architects, and expert handypersons alike, the project photography within will guide you stepby-step in the creation of an outdoor kitchen project, from the careful process of measuring a template, to building a mould, to casting, curing, and installation.

These titles are available to purchase online or to borrow from the CCANZ Library (library@ccanz.org.nz).

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CCANZ Library Listed below is a small selection of recently acquired material by the CCANZ library. email library@ccanz.org.nz TO BORROW. THE CONCRETE HOUSE: BUILDING SOLID, SAFE AND EFFICIENT WITH INSULATING CONCRETE FORMS BY PIETER A. VANDERWERF Prospective homeowners will welcome this introduction to a durable, energyefficient new building technology: insulating concrete forms (ICFs).

Organized in an accessible Q+A format, it will help homebuyers decide whether an ICF is right for them. Every aspect of planning and construction is covered, including the intricacies of building a concrete house, from choosing a contractor to selecting a suitable design for the system. There’s advice on how to make sure construction goes smoothly, and explanations of how ICF homes differ from conventional ones and why they cost less to maintain.

Designing Comfortable Homes

ARCHITECTURE MATERIALS: CONCRETE BY FLORIAN SEIDEL Concrete is the most widely-used building material in the world today. Some seven billion cubic meters of concrete are used in construction each year, more than one cubic meter per person. Concrete is stone created by human hands in which the human creative spirit is reflected together with the timelessness and serene appeal of an ‘everlasting’ material. This volume presents 25 contemporary buildings from all over the world in more than 300 illustrations and architectural drawings: particularly interesting examples of the interior and exterior use of concrete in construction

Library Quiz To go in the draw to win a copy of The Concrete House: Building Solid, Safe and Efficient With Insulating Concrete Forms by Pieter A. VanderWerf answer the following simple question:

Using an appropriate combination of glass, thermal mass and insulation, New Zealand homes can be naturally warm in winter and cool in summer.

Designing Comfortable Homes provides all the concrete answers to how passive solar design can enhance thermal comfort and reduce energy demands.

The Department of Building and Housing has recently changed made changes for Structure (Building Code clause B1), in particular, all concrete slabs on ‘good ground’ must be reinforced with ductile steel and tied to perimeter foundations. What is the grade of reinforcing steel specified by the Department?

Email your answer to library@ccanz.org.nz.

Entries close Friday 27 April 2012.

Congratulations to Greg Davies of Beca, who correctly answered the June / July 2011 Library Quiz to receive a copy of Displacement Based Seismic Design of Structures by M.J.N. Priestley, G.M. Calvi and M.J. Kowalsky.

Request your FREE copy of Designing Comfortable Homes now

COMING HOME TO CONCRETE

www.ccanz.org.nz

Cement & Concrete Association of New Zealand

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CONTACTS

News from the Associations

New Zealand Ready Mixed Concrete Association Ph (04) 499 0041 Fax (04) 499 7760 Executive Officer: Rob Gaimster President: Jeff Burgess www.nzrmca.org.nz New Zealand Concrete Masonry Association Ph (04) 499 8820 Fax (04) 499 7760 Executive Officer: David Barnard President: Jason Savage www.nzcma.org.nz Precast NZ Inc. Ph (09) 638 9416 Fax (09) 638 9407 Email: ross.cato_precastnz@xtra.co.nz Executive Officer: Ross Cato President: Andrew Sinclair www.precastnz.org.nz New Zealand Concrete Society Ph (09) 536 5410 Fax (09) 536 5442 Email: concrete@bluepacificevents.com Secretary/Manager: Allan Bluett President: Jason Ingham www.concretesociety.org.nz New Zealand Master Concrete Placers Association Ph (06) 873 4428 Fax (06) 873 4429 Email: office@mcpa.org.nz www.mcpa.org.nz

NEW ZEALAND CONCRETE SOCIETY (NZCS) NZCS VICE PRESIDENT - CARL ASHBY Carl Ashby stepped up his involvement with the Society because of the value it offers people in the concrete industry and its total approach to the industry.

The Society’s new Vice President is Wellington-based and Structural Group Manager for Opus International Consultants. During his 16 years as a Society member, Carl has attended most of the annual conferences.

He says he has always got a lot of value out of the Society, particularly after the Kobe and San Francisco earthquakes in the 1990s. In 1996, the new concrete standard NZS 3101:1995 came out, and included a lot of the lessons learned from those earthquakes.

“At that time a vast amount of information was released on the performance of concrete buildings and seismic engineering, and the NZCS was involved in the dissemination of that knowledge. That’s when I became very interested in the Society’s work.

“The NZCS spent the next few years holding seminars to teach the engineering profession and, as a young engineer, I found them invaluable.”

Carl has been involved at committee level with other professional institutions, including the Structural Engineering Society (SESOC) and the NZ Earthquake Engineering Society (NZSEE) for similar reasons - they provide useful information.

“The thing I particularly like about the NZCS is that it covers the entire industry, from academics to people who make and place concrete, including contractors and engineers. It’s a total approach to the industry. I like that about the Society and wanted to contribute more. I believe in the future of structural concrete in New Zealand.”

Carl has a strong working relationship with the Society’s President, Associate Professor Jason Ingham, and has worked with him on SESOC and the NZSEE. With 18 years of technical experience, Carl holds a Bachelor of Engineering from Canterbury University, and has worked in client and project team liaison on a range of commercial, industrial, residential, civil and infrastructure projects.

Carl is an IPENZ Practice Assessor, and on the Management Committee for NZSEE and SESOC (he’s the Wellington Structural Group Chair), and mentors staff for CPEng assessment and advancement in structural engineering.

steel fibres for warehouse and industrial floors

For more information contact: Steve Skidmore 0800 60 60 20 sskidmore@maccaferri.co.nz www.maccaferri.co.nz

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