HDG Magazine Summer Issue 2023 by Galvanizers Association

HOT DIP GALVANIZING

Summer 2023

GAGA Awards Winners | 2 Holton Studios, Holton le Clay | 20 Scapa Flow Museum, Scotland | 22 LIKO-Vo, Czech Republic | 26

International Magazine ISSN 1363-0148 www.hdgmagazine.co.uk

Summer 2023 HOT DIP GALVANIZING

Editorial Welcome to our new reconfigured HDG magazine. We are trialling combining our four issues to a double summer and winter edition. In our new bumper ‘Summer Edition’, we feature articles that deal with many important issues within today’s construction industry – circular design principles, fire protection and standards. Circular design was an important theme within our 2023 GAGA winners and entrants. A diverse range of projects from architecture through to art were recognised by the judging panel. All provide creative and important solutions for our built environment . Our winners feature: the sustainable restoration of Southend-on-Sea Pier, a rural community project, an under the arches cinema and a sculpture trail. Our general articles include a truly collaborative project in the Orkney Islands, which between client and design teams provided passionate and dedicated advocacy to reinvigorate an important local museum. In Dusseldorf , galvanized steel has provided an ideal solution for a data centre. The coating has not only provided long term corrosion protection for the steelwork but also achieved R30 fire protection - a two-in-one cost effective solution!

Iqbal Johal, Editor

Note for readers: Hot Dip Galvanizing – An international journal published jointly by the galvanizing associations of Germany, United Kingdom & Ireland. Edited by: I. Johal, H. Glinde (Editor in Chief). Published by: Galvanizers Association, Wren’s Court, 56 Victoria Road, Sutton Coldfield, West Midlands B72 1SY, UK; Tel: +44 (0) 121 355 8838 E-Mail: ga@hdg.org.uk, Website: www.galvanizing.org.uk This magazine may not be copied without the written permission of the editor © 2023.

Photo front cover | Visual Air

We are changing the way we issue hot dip galvanizing magazine. We will be experimenting with producing just two issues a year – Summer and Winter, they will however be double issues, so you will not miss out on any of our glorious examples of galvanized steel projects.

HOT DIP GALVANIZING Summer 2023 1

by Iqbal Johal

GAGA 2023 The Winners

The 2023 GAGA competition saw its winner’s being recognised at a lunch in London. Our competition attracted a diverse range of projects across a broad range of categories from architecture through to sustainability. Circular design was a key theme amongst this year’s entrants with demountability and reuse being a key component within our cohort of entrants and winners.

Social improvement was also seen as an important element within many entries, with two winning projects emphasising the importance of local regeneration and the provision of flexible community space both in a rural and urban context.

1 | GAGA 2023 winners with their unique galvanized watering cans

Photos | Galvanizers Association

Summer 2023 HOT DIP GALVANIZING

Architecture Winner Architecture 00 / Public Works Loughborough Junction LJ Works demonstrates how residents can take an active role in local regeneration by claiming land for long-term public use - creating space for self-sustaining local economies governed by and for the community. The project brings industry, growing and community action together as a supportive ecosystem to address systemic social issues and take some control of local regeneration. On the 2,000 m2 site, two buildings deliver over 1,000 m2 of light-industrial workspace dedicated to local textiles, food producers, and makers. These low-rent studios and co-working spaces operate alongside the community growing project, Loughborough Farm, and the Platform community cafe. A "fabric first" approach was adopted, incorporating high insulation levels, thermal mass, and south-east facing windows to maximize solar heat gains and natural ventilation for cooling during summer. To minimize energy demand and construction costs, the main circulation spaces are integrated into uninsulated greenhouses, serving as draft lobbies that moderate the temperature between the interior and exterior. (Content provided by Architecture 00)

Photos | Lorenzo Zandri

HOT DIP GALVANIZING Summer 2023 Principles of Circular Economy implemented: 1. Galvanized steel elements for disassembly and reuse, and eventual recycling. 2. Local manufacturing – WikiHouse construction with local CNC Plywood. 3. Prioritising local SME's – Local building contractor chosen and contract stipulated the use of local SME's. 4. Construction training – Building contract stipulated the contractor to offer CSCS training and construction experience in partnership with the Marcus Lipton Youth Centre. 5. Community build opportunities – WikiHouse open build days. 6. Closed loop food and energy system onsite: – food grown on site – cooked and sold in the community – café food waste goes into the anaerobic digester – creating biogas and fertiliser – fertiliser used to grow more food onsite and biogas used to heat the building.

Summer 2023 HOT DIP GALVANIZING

Sustainability Winner IDK Architects Outside The building is part of a rural community development in South Devon which looks to add to the area’s social and economic life. It sits amongst a two-acre plot which has space for skateboarding, smallscale farming, and play areas, hosting a cafe, event space, ceramics studio and surfboard shaping workshop. Sited in a designated Area of Outstanding Natural Beauty, where near-barren arable monocultures are often preferred over mixed use regenerative practices, the project serves as a case study for new forms of hyperlocal, sustainable rural development. Derived from an existing dilapidated structure, the steel frame was galvanized in part because the building combines an internal insulated volume and an exposed flexible winter garden space. It was felt that the protection from galvanizing was essential to the external area. All flashings and reveals were galvanized to contrast the fibre cement and the exposed structural frame exists as a unified language. The project ethos sought to deliver maximum impact through minimum means and an approach that celebrated and supported local supply chains throughout the design and procurement of the project. (Content provided by IDK Architects)

Photos | Toby Coulson

HOT DIP GALVANIZING Summer 2023

Summer 2023 HOT DIP GALVANIZING

Engineering Winner UK Industrial Services Southend-on-Sea Pier Southend-on-Sea Pier is the city’s most treasured historical icon putting Southend on the map as well as into the record books. The pier is owned, managed and maintained by Southend City Council. The original timber pier was constructed in the 1800’s, it was superseded by the Iron Pier designed by James Brunless and constructed in 1889. The pier is a Grade II listed building and officially the world’s longest pleasure pier reaching out 1.34 miles into the Thames Estuary. The pier played a role in both World Wars, a true survivor with an incredible history and also boasts the first pier railway to be built in the country in 1890, the narrow gauge railway is still used to transport passengers to and from the pier head. Southend City Council has invested heavily in the pier over recent years; several structural condition surveys were commissioned identifying significant structural defects requiring repairs to be carried out to safeguard the future of the pier. The most urgent defects were prioritised and a 5 year rolling programme began. The anchor bays form the main structural supports for the pier, providing rigidity whilst allowing contraction of the structure. They are formed from cast iron piles, 9.1 m steel beams, 3.5 m steel deck beams, forged cross bracing, tension rings, bull rails, pile caps, clamps and heavy duty nuts and bolts, and washers. There are 19 anchor bays supporting the pier, repair work to anchor bays are phased and the value of the work package is

HOT DIP GALVANIZING Summer 2023

typically in the order of £1.5m. Where existing beams have been graded repairable and deemed suitable for reuse, the beams will be painted and reused in areas of the pier subjected to minimal load and forces. Reduction of carbon footprint was a key principle with as many original wrought iron beams being repurposed without compromising the structural integrity of the pier. All new steelwork is galvanized to provide a durable robust coating. The beams were painted to enable them to blend in with the existing darker appearance of the historic structure, helping to gain acceptance from Planners and Historic England. (Content provided by UK Industrial Services)

Photos | Visual Air, Garry Stickland

Summer 2023 HOT DIP GALVANIZING

Detail Winner Takero Shimazaki Architects Curzon Camden Cinema Camden’s new cinema represents the adaptation and renewal of the once industrial infill lining its viaducts. The ambition sought to retain as much of the landlords pre-existing shell as possible, re-purposing the building fabric installed as part of the larger Hawley Wharf regeneration. Working with the inherited materials, new architectural elements were inserted with their own language which now define the public spaces of the cinema. Working with plywood, galvanized metal and structural steel, the architects wanted to elevate otherwise modest building materials with the addition of stone and render. The intention was a sense of ‘otherness’, something different to what was there before. It was important not to conform to the often appropriated industrial warehouse typology. Instead, the interventions are individual arched spaces with expressed façades, colours, material textures, tactility, fabric, light and shadow. The notion of lightness and weight occurring simultaneously was explored. The existing arches have a sense of material, structural and historical weight. New elements were inserted using as little new material and resource as possible.

HOT DIP GALVANIZING Summer 2023 The auditoriums, café and bars are connected, yet separate. They are individual spaces, each with their own door to the street. The project proposes an architectural scenario of urban niche-like parasitic interventions, fitting into the existing industrial infrastructure - adapting into a re-use architecture of lightness and weight. (Content provided by Takero Shimazaki Architects)

Photos | David Grandorge

Summer 2023 HOT DIP GALVANIZING

Duplex Winner Kris Grant Architect Rescobie Pavilion Rescobie Pavilion is a steel framed garden building, perched above a stone base, in the grounds of a 19th century schoolhouse in rural Angus, Scotland. It sits comfortably in the landscape, an exposed site with easterly views over Rescobie Loch and westerly views over the client’s beautiful but steeply sloping garden. The clients wanted a new building to maximise their enjoyment of the garden, with walls that slide open to allow meals to be enjoyed in the sunshine whilst sheltered from the wind. Steel was chosen as the pavilion’s primary structure for its ability to cantilever, allowing an expressive frame with a large extent of glazing to fill the space with light and provide the experience of being outside even when inside. The steel was galvanized and then

HOT DIP GALVANIZING Summer 2023 finished with an epoxy coating, the former providing corrosion protection and the latter, the required aesthetics, in this exposed environment. A broad, wrap-around balcony is fixed to the main structure and provides outdoor socialising space suspended above the garden, amongst the tree branches. It is also made of galvanized steel with the balustrade detailed to take full advantage of the thinness of steel and fine mesh panels to maximise transparency between the building and the garden. (Content provided by Kris Grant Architect)

Photos | Dapple Photography

Summer 2023 HOT DIP GALVANIZING

Art Winner Bill and Peach Shaw History of Bideford

Bideford's rich history comes alive through thoughtfully crafted sculptures that embody its Elizabethan legacy. The Cooper Sculpture, celebrating the town's barrel-making street, and the Bideford Merchant sculpture, reflecting its vibrant trade history, stand as galvanized testaments to durability and aesthetic finesse. These artworks not only capture Bideford's past but also unite it with the present, emphasizing the enduring bond between art, history, and the galvanizing process. Galvanizing not only preserves its integrity but also provides an alluring finish that mimics the patina of time, a perfect match for the sculpture's theme of historical resonance. These galvanized sculptures stand as tributes to Bideford's heritage, reminding us of the town's enduring spirit and connection to its past. (Content provided by Bill and Peach Shaw)

Photos | Bill and Peach Shaw

HOT DIP GALVANIZING Summer 2023

Summer 2023 HOT DIP GALVANIZING

Architecture Award: Highly Commended Knox Bhavan Architects March House Knox Bhavan were commissioned to design a house to be a long-term primary residence on the banks of the Thames. This was an opportunity to design and construct a beautiful, flood resistant, energy-efficient house to serve the client's current and future needs. The design concept was for a single-storey modest timber-clad building to melt into the landscape whilst appearing to hover above the ground. The house is raised off the ground on slim galvanized steel supporting legs upon which sits a steel chassis supporting the insulated timber framed cassettes forming the buildings envelope. This insulated envelope is clad with stained larch which follows a language of narrow planed boards for the window and shutter zones and wide sawn boards filling the space between. The house needed to withstand the 100-year, climate change enhanced predicted flood level. Galvanized steelwork is used throughout the project, concentrated on details of the scheme that fall below the river’s floodplain. Lightweight galvanized steel stilts support a galvanized chassis of elegant universal beams set back from the edge of the main house which appears to float over the garden. Three galvanized staircases sit in the flood zone and reach up towards the house. Each staircase is carefully detailed to be elegant, lightweight, and robust in flood conditions. (Content provided by Knox Bhavan Architects)

Photos | Edmund Sumner

HOT DIP GALVANIZING Summer 2023

Sustainability Award: Highly Commended [Y/N] Studio Bradbury Works Bradbury Works in Gillett Square, Dalston, has recently re-opened its doors to new and returning tenants. The new building includes the refurbishment of 600 m2 of existing affordable workspace, the replacement of ten mini retail units, and the provision of almost 500 m2 of extra workspace in a two-storey extension. Bradbury Works is the next step in the evolving story of one of the most unique and community focused public spaces in London. The cladding reflects the colour of the sky and surroundings during the daytime and glows at night, unifying the form of the building as it wraps around the covered terrace, stair core and workspaces. The façade is fixed to a galvanized steel secondary structure. Both vertical and horizontal rails are provided to allow for metal rainwater pipes to be concealed behind the cladding and giving the structure a sense of lightness. (Content provided by [Y/N] Studio)

Photos | French + Tye

Summer 2023 HOT DIP GALVANIZING

Industrial by Holger Glinde

Elegence

Tram Depot Line T9, Paris In 2021, the 10.3 km long tram line T9 was opened, connecting Paris with Orly. It is capable of transporting up to 80,000 people per day. The new line includes a tram depot, maintenance centre, and the central command centre. The buildings, designed by Ferrier Marchetti Studio, are located on a 4.4-hectare site and pay homage to the 19th century factories that line the Seine with their sloping roofs.

The depot will form part of the new Grand Voeux district, which has been earmarked for further development and is also meant to open up the previously inaccessible Seine riverbank. A close connection between architecture and landscape will characterise the new district. Green areas surround the depot, and there is also a courtyard with a covered garden.

1 | T he new 10.3 km long tram line T9, connects Paris with Orly 2 + 3 | T he use of galvanized steel and glass aids both durability and provides transparency

HOT DIP GALVANIZING Summer 2023 1

2 The striking depot roof with its folded silhouette give the functional buildings a high design quality and outline a skyline when approached from a distance. Hot dip galvanized steel structures, in conjunction with large glass surfaces, emphasise the industrial character of the buildings and elevate them to the landmark of the new district. Large windows allow for unrestricted views of the depot, even at night, as there is almost continuous activity, with only a few hours of closure per day. In addition to design and functionality, durability was of great importance which is reflected in the decision to use galvanized steel.

Photos | Luc Boegly Architects | Ferrier Marchetti Studio

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Rural by Iqbal Johal

Workspace Holton Studios, Holton le Clay Located on the edge of the charming village of Holton le Clay, Holton Studios is a new development comprising of six workspaces available to let. The first phase of a larger project, the building is situated on the edge of what will eventually become a communal courtyard for the local community. With neighbouring buildings constructed in brick with concrete-tiled roofs and metal roller-shutter doors, it was important for Holton Studios to blend in while still maintaining its unique identity. The design was aimed to create a building that not only found its language from the scale of adjacent buildings but also from a more agricultural typology.

1 | T he design was aimed to create a building from a more agricultural typology 2 | T he cantilevered roof creates a covered public walkway along the length of the building 3 | T he galvanized steel frame allowed for easy formation of vaulted ceilings internally

The linear plan of the building features a pitched roof, with the communal courtyard side of the roof cantilevered to create a covered public walkway along the length of the building. The use of a galvanized steel portal frame allowed for the easy formation of vaulted ceilings internally and the cantilevered external walkway roof, without the need for additional cross-bracing.

20 1

HOT DIP GALVANIZING Summer 2023

The interior of each unit is lined with warm birch plywood sheets, providing a contrast to the fibre-cement sheets used for external cladding. The main workspace is generously proportioned and vaulted, with large timber-framed windows and an opening casement for natural ventilation. This gives it a spatially generous feel, and the timber lining gives the interior a soft, warm ambience in contrast with the utilitarian feeling of most parts of the exterior. Security shutters are provided in the form of sliding galvanized panels with the same proportions as the fibre-cement panels. Galvanized steel shutters were selected for their robustness and aesthetic appeal. Both end gables are clad in fine larch strips, which have been stained Nordic red to serve as a transition between the surrounding red brick buildings and the semi-agricultural design language of Holton Studios. The materials for Holton Studios have all been selected, with the exception of the stained larch, as off-the-shelf products. This decision was made to ensure the building maintains its semi-agricultural feel while remaining easily adaptable for future requirements.

Internally, party walls dividing the studios have been constructed using jumbo metal studs sheathed in several layers of acoustic and fire board and then veneered with sheets of birch-faced ply. This construction allows openings to be formed within the party walls, providing the opportunity for studios to be interconnected if required. The timber windows and door facing the future central triangular courtyard filled with acer trees are made from Accoya acetylated wood, chosen for its longevity and resistance to rotting. In contrast with the softer-looking timber, the external shutters and rear access door are made from galvanized sheet steel. Holton Studios provides a unique, attractive workspace option for small businesses, with a design that is both functional and visually appealing. The combination of warm, natural materials and agricultural-inspired design elements make for a welcoming and comfortable work environment. (Content provided by Holton Studios)

Photos | David Grandorge Architects | Holton Studios

Summer 2023 HOT DIP GALVANIZING

Respectful by Iqbal Johal

Extension

Scapa Flow Museum, Scotland The Scapa Flow Museum, located on the Orkney Islands, has undergone an extension to better showcase its collection of artefacts and interpretative spaces. The former Pumping Station, which served as a wartime fuel depot, was not originally designed for museum display, and provided an increasingly poor environment for fragile artefacts. The addition of the extension has allowed these pieces to be displayed safely while also clearing the original building‘s rooms for the proper display of the amazing machines it houses.

The new extension is deliberately deferential in form, using mute materials with minimal openings. The glazing is limited to the new entrance, the café, and a frameless strip of glass that both connects and separates the two buildings. The extension‘s atmospherecontrolled black-box space now houses the main collection of artefacts.

1 | T he new building stands respectfully apart from the old, with the two linked by a narrow strip of glazing 2 + 3 | T he new building‘s steel work and mechanical systems are fully galvanized and set against anthracite roof and wall cladding

The project was a true collaboration between the client and design teams, with the Orkney Islands Council‘s Cultural Services and Development, and Infrastructure teams providing passionate and dedicated advocacy to make the project possible. The new building stands respectfully apart from the old, with the two linked by a narrow strip of glazing. The original building‘s steelwork is painted, while the new building‘s steelwork and

22 1

HOT DIP GALVANIZING Summer 2023 2 mechanical systems are fully galvanized and set against anthracite roof and wall cladding. This inversion of the original building‘s internal colour palate works to dramatic effect. Internally, the project took a light touch, with corroded steelwork being repaired and repainted in Ministry of Defence Dark Camouflage Grey to express it internally against the white of the newly introduced roof and gable cladding. New electrics and lighting were installed throughout using galvanized conduit, differentiating the new from the old sections of conduit, which were left as found. One noteworthy feature is the use of boom netting – an armour of interlocked steel rings – in the design of the extension. A small section of the netting was utilized to encourage a desired route through the building, while also maintaining separation and permeability in the channel between the two buildings. The Scapa Flow Museum‘s extension has successfully accomplished its principal purpose of conserving the category A listed Pumping Station and its extensive collection of fragile wartime artifacts. The juxtaposition of the original painted steel frame alongside the galvanized new steel work, with the clear separation between the two, allows both buildings to be read independently. Although they work as one, the Pumping Station is an artifact in its own right, and it was important to showcase it as such. The project has been successful in both colour and material terms due to the use of galvanized finishes throughout the introduced elements. The Scapa Flow Museum‘s extension is a testament to the importance of careful consideration in the design and construction of museum spaces. By respecting the original building‘s history and design while adding new elements to better serve its purpose, the Museum has been transformed into a space that will undoubtedly inspire visitors for years to come. (Content provided by LDN Architects)

Photos | Ross McEwen, Orkney Islands Council Architects | LDN Architects, Fionn McArthur

Summer 2023 HOT DIP GALVANIZING

Sustainable by Holger Glinde

Revival

Swissgrid Museum, Switzerland In the past, it was common practice to reuse building materials from ruins and demolished houses for new construction. However, with technological advancements, easier access to raw materials, and the production of composite materials, the frugal and sustainable use of building materials through reuse was abandoned. A new museum for the Swiss energy supplier, Primeo Energie, recalls the tradition of reuse and gives numerous building materials a second life. Designed by architects from Rapp AG, Basel, the building incorporates, among other things, decommissioned high-voltage pylons, former boathouse planks and discarded washbasins.

By reusing materials, the ecological footprint of the museum has been significantly reduced. The reuse also aligns with the museum's idea, which as a knowledge centre aims to raise awareness of the energy transition and the importance of climate neutrality. The three-story building is a timber-framed construction which spans of around seven meters. A two-story spiral staircase is covered with reused wooden planks, as are the wooden floorboards of the upper floors. Other old building components in the interior come from a building component exchange, including a complete kitchen. The wet areas are almost exclusively equipped with discarded elements such as washbasins, partitions, or fittings. A central role is played by the 60-year-old high-voltage lattice towers, which were purchased as scrap material from the grid operator Swissgrid. They consist of galvanized and subsequently coated steel profiles. Instead of recycling them, they wrap around the new galvanized, circular pergolas, which also form a steel lattice structure around the wooden cube. The former power pylons will serve as climbing frames

HOT DIP GALVANIZING Summer 2023

1 | T he three-story building is a timber-framed construction with an external galvanized steel frame

1 for plants and thus enable shading to improve the indoor climate in the building. In addition, the galvanized and coated steel profiles of the lattice towers were reused as railing elements in the interior. The reuse of galvanized steel has a long tradition, for example, in scaffolding construction. Increasingly, galvanized steel is also being reused in buildings due to its durability.

2 | T he 60-year-old high-voltage lattice towers galvanized and coated have been resued to wrap around a new inner galvanized steel frame of the buidling 3 | T he galvanized and coated steel profiles of the lattice towers were reused as railing elements in the interior

Photos | Beat Ernst Architects | Rapp AG

Summer 2023 HOT DIP GALVANIZING

Green by Holger Glinde

façades

LIKO-Vo, Czech Republic Green façades are in vogue and are not just a design element. They can protect buildings from overheating in summer, thereby rendering air conditioning for building cooling unnecessary. They also contribute to the well-being of building users. Although their advantages can also be demonstrated in industrial construction, green façades are rarely found in this sector. An exception to this is Liko-Vo.

HOT DIP GALVANIZING Summer 2023

Typical exhibition halls and warehousing are usually executed as "tin cans" which, in summer, often heat up to an extreme degree due to solar radiation, making work unbearable. In contrast, LIKO-Vo utilizes the concept of a "living building", which contributes to thermal stabilization in a natural way and ensures comfortable temperatures even in high summer. This is achieved through a green roof, a green façade, a retention pond, and other technologies. The walls inside the hall are also green. Hot dip galvanized steel was used for the hall skeleton, the roof substructure, and steel components in the outdoor area such as stairs, railings, and paths. Hot dip galvanized steel is not only characterized by longevity and robustness, but can also be reused after dismantling and is ultimately recyclable without any loss of quality.

2 1 | Green façades render air conditioning for building cooling unnecessary 2 | Hot dip galvanized steel was used for the frame, the roof substructure, and steel components in the outdoor area 3 | A green roof, a green façade ensures comfortable temperatures even in high summer

Photos | Anna Vavríková, Mafra Architects | Fránek Architects

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Fire-Proof by Holger Glinde

Data

Data centre, Germany 1 | T he hot dip galvanized steel structure meets the R30 requirements

A large building in the immediate vicinity of the Düsseldorf-Süd motorway junction resembles, at roof level, a Star Wars spaceship. The building, which is around 280 m long and up to 125 m wide, houses various IT companies that operate data centres and offer cloud computing solutions. In order to increase capacity, an unused roof area was redesigned as a technical installation space for one of the data centres.

HOT DIP GALVANIZING Summer 2023

The approximately 2,600 m2 area was equipped with cooling units that serve to air-condition the data centres. As data centres produce a lot of waste heat due to their high energy requirements, they have a significant cooling demand and therefore require a well-functioning waste heat management system. Around a quarter of the energy required by data centres is used for cooling and air conditioning. To ensure accessibility and accommodate the typical labyrinth of cooling pipes, the cooling units were mounted on platforms above the roof, creating two levels. For this purpose, a complex hot dip galvanized steel structure was developed consisting of columns, beams, and trusses. To be able to service the cooling technology, access routes were created between the cooling systems using hot dip galvanized stairs, railings, and grating.

A fire resistance of 30 minutes (R30) was required for the load-bearing steel components. This was proven by the Nowydom engineering firm, which carried out calculations and demonstrated that the hot dip galvanized steel structure met the R30 requirements. This eliminated the need for passive fire protection measures. Thus, hot dip galvanizing not only ensures permanent corrosion protection, but also contributes to the R30 fire protection of the steel structure.

2 + 4 | A complex hot dip galvanized steel structure was developed consisting of columns, beams, and trusses to support the cooling units

3 | Access routes were created between the cooling systems using hot dip galvanized stairs, railings, and grating

Engineer | Nowydom Photos | Nowydom

Summer 2023 HOT DIP GALVANIZING

Moderate by Luke Underwood

changes

Hot Dip Galvanizing Standard – EN ISO 1461 : 2022 – Published The European and International standard covering post-fabrication hot dip galvanizing of steelwork, EN ISO 1461 – Hot Dip Galvanized Coatings on Fabricated Iron and Steel Articles – Specifications and Test Methods has been revised, with the new version of the standard published in 2022. The revision of EN ISO 1461 was initiated to make improvements to the standard and to align it with the latest developments from within the industry.

1 | T he measurement of coating thickness can be conducted in a simple and non-destructive process 2 | Galvanized steel ready to be transported to site

EN ISO 1461 contains requirements for the hot dip galvanized coating thicknesses which are proportional to the section thickness of the steel being galvanized. For example, for steel greater than 6 mm thick, the minimum mean coating thickness requirement is 85 microns, which offers a very high level of corrosion protection in most service environments. The actual thickness of galvanized coating achieved varies with steel section Minimum galvanized coating thickness and mass on samples that are not centrifuged Local galvanized coating thickness (minimum)

Local galvanized coating massa (minimum)

Mean galvanized coating thickness (minimum)

Mean galvanized coating mass (minimum)

�m

g/m2

�m

g/m2

Steel: > 6 mm

505

610

Steel: > 3 mm to ≤ 6 mm

395

505

Steel: ≥ 1.5 mm to ≤ 3 mm

325

395

Steel: < 1.5 mm

250

325

Castings: > 6 mm

505

575

Castings: ≤ 6 mm

430

505

Article and its thickness

Note: This table is for general use: individual standards can include different requirements including different categories of thickness . Local and mean galvanized coating mass requirements are set out in this table for reference in such cases of dispute. a Equivalent galvanized coating mass using a nominal density of 7,2 g/cm3 (see Annex D)

size, surface profile and surface composition. In practice, coating thicknesses are often much more than the minimum specified in this standard. Thicker coatings than those set out in EN ISO 1461 can offer additional protection for use in particularly aggressive environments and can be specified in conjunction with EN ISO 1461. It should, however, be emphasised that for most applications, thicker coatings are rarely necessary. The standard includes the surface finish requirements of the galvanized coating, such that it should be continuous and relatively smooth (i.e., no spikes or sharp edges). Variation in coating appearance (e.g., cellular pattern or dark grey areas) or some surface unevenness is not cause for a rejection; these are inherent properties of hot dip galvanizing and are typically determined by the steel’s reactivity. A detailed inspection procedure is also outlined which includes the number of reference areas which are to be taken on each article, and the number of articles which are to be included in the control sample. This ensures that a thorough, non-destructive, statistical analysis is conducted across galvanized articles. The most significant changes to EN ISO 1461 concern the galvanizing of ultra-low reactive steels, coating thickness measurements on ancillary elements, removal of flux residues and zinc ash, the renovation of galvanized steelwork and reference to long term performance of galvanized coatings in atmospheric environments. There has been no fundamental change to the method of assessment of coating thickness, but allowances

HOT DIP GALVANIZING Summer 2023

Minimum galvanized coating thickness and mass on samples that are centrifuged Local galvanized coating thickness (minimum)

Local galvanized coating massa (minimum)

Mean galvanized coating thickness (minimum)

Mean galvanized coating mass (minimum)

�m

g/m2

�m

g/m2

Articles with threads > 6 mm diameter ≤ 6 mm diameter

40 20

285 145

50 25

360 180

Other articles (including castings) ≥ 3 mm < 3 mm

45 35

325 250

55 45

395 325

Article and its thickness

Note: This table is for general use: standards for galvanized fasteners and individual products standards can have different requirements: see Clause A.2, h). Local and mean galvanized coating mass requirements are set out in this table for reference in such cases of dispute. a Equivalent galvanized coating mass using a nominal density of 7,2 g/cm3 (see Annex D)

for measurements on ancillary elements and ultra-low reactive steels have been introduced. The revised standard states that thickness measurements should not be taken on ancillary elements (e.g., brackets) unless specifically requested. Recognition that certain steel compositions can exhibit ultra-low reactivity during galvanizing (i.e., cannot satisfy the standard minimum coating thickness requirements) has been introduced. Articles produced from steel with a section thickness greater than 3 mm which have a composition of ≤ 0.01 % silicon AND an aluminium content > 0.035 %, that exhibit ultra-low reactivity during galvanizing, can now be subject to lower coating thickness requirements. The variation to the standard requirements must be included in the Declaration of Compliance if one is to be provided. The updated version of the standard now acknowledges that if ‘access is restricted, for example, inside hollow sections’ flux residues and zinc ash are permissible. The guidance offered on the renovation of uncoated or damaged areas is now more extensive and includes detailed specifications for zinc-containing paints, commonly used to repair galvanized coatings in the unlikely event of damage or an uncoated area post galvanizing.

EN ISO 1461:2022 now references ISO 9224 – Corrosion of metals and alloys – Corrosivity of atmospheres – Guiding values for the corrosivity categories in the Annex ‘Corrosion resistance of galvanized coatings.’ ISO 9224 provides information on the average and steady-state zinc corrosion rates which are useful for predicting long-term performance of galvanized coatings in atmospheric environments. Long-term corrosion rates for zinc are lower than first year corrosion rates because of the development of a protective patina formed on the initial galvanized coating over time. For most applications, where galvanized steel articles are exposed to atmospheric conditions, the galvanized coating life in those conditions is proportional to the thickness of the galvanized coating. The revised standard has been welcomed by industry and the specifying marketplace, owing to the up-to-date information and comprehensive improvements to the relevant sections. 2

Galvanizing Delight

The Impact Hub Berlin at CRCLR-House has opened its doors, providing a space for individuals focusing on the topics of circular economy and sustainability. The interior design by LXSY Architects demonstrates how preserving existing structures and using sustainable, renewable, and recycled materials can positively impact the construction industry of the future. Approximately 70% of the materials and products used in the project are recycled or sustainable. High-quality, reused and new sustainable materials are utilized in their natural state, including striking handrails made from hot dip galvanized gratings. Architects| LXSY Architekten Photo | Studio Bowie