BUILDING TECHNOLOGY 1 (BLD61403) PROJECT 1: INDUSTRIALISED BUILDING SYSTEM (IBS)
BLOCKWORK SYSTEM KOK SZE KUAN 0327896 | LEE XING SHEN 0327496 | OOI JUN YANG 0327896 HO PEI SAN 0332992 | TAN ZI WEN 0327759 | WESLEY WONG TECK WON 0330496
TUTOR: MR. MOHAMED RIZAL MOHAMED
Table of Content 1 Introduction 1.1 Introduction to IBS 1.2 Types of IBS in Malaysia 1.3 Advantages and Disadvantages of IBS in Malaysia 1.4 Standard Design Workflow of IBS 1.5 Blockwork System 1.5.1 Advantages and Disadvantages of Blockwork System 1.5.2 Types of Concrete Blocks in Malaysia 1.6 Case Study 1.6.1 SMK Bandar Enstek, Negeri Sembilan 1.6.2 The Bungalow, Kota Bahru
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4 Schedule of IBS Components 4.1 Concrete Masonry Units (CMU) Blocks Wall 4.2 Precast Hollow Core Slabs 4.3 Precast Staircase 4.4 Prefabricated Doors 4.5 Prefabricated Windows 4.6 Precast Lintels 4.7 Prefabricated Steel Roof Trusses
2 Concept and Framework 2.1 Proposed IBS System 2.2 Features and fabrication process of IBS components 2.2.1 Cast In-Situ Strip Foundation 2.2.2 Precast Concrete Hollow Core Slab 2.2.3 Precast Concrete Staircase 2.2.4 Prefabricated Steel Roof Truss 2.2.5 Concrete Masonry Units (CMU) Block Wall 2.3 Sequence of Construction 2.4 Sequence of Construction of Model
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5 Construction Details 5.1 Cast in-situ Strip Foundation 5.2 Concrete Masonry Units (CMU) Block Wall 5.3 Precast Concrete Hollow Core Slab 5.4 Precast Concrete Staircase 5.5 Prefabricated Steel Roof Truss 5.6 Doors and Windows 5.7 Ceiling 5.8 Toilet Pod 5.9 Finishes
3 Technical Drawings 3.1 Architectural Drawings 3.1.1 Plans 3.1.2 Elevations 3.1.3 Sections 3.2 Structural Drawings 3.2.1 Structural Foundation Plan 3.2.2 Structural Wall Plans 3.2.3 Structural Floor Plans
3.2.4 Structural Roof Plans 3.3 Exploded Axonometric
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6 IBS Score Calculation
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7 Conclusion
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INTRODUCTION
01 Introduction 1.1 Introduction to Industrialised Building System (IBS) An Industrialised Building System (IBS) refers to a techniques of construction that is used broadly by the industry and government in Malaysia to represent the adoption of industrialisation and the use prefabrication of components in building construction. In IBS, the components are manufactured in a controlled environment, either at site or off site, and transported, positioned and assembled into construction works. The building components in Industralised Building System (IBS) includes walls, floors, beams and staircases. The implementation of IBS can be done in two system, either an open IBS or closed IBS. Open IBS allows the combination of prefabricated building components from various factories and the components are compatible with each other to be used in any building project. A successful implementation of this system requires a modular coordination. Closed IBS is where all building components have only specific designs for specific projects. This system does not allow interchangeability of components from different factories.
Construction Industrial Development Board (CIDB) serves to regulate, develop and facilitate the construction industry in Malaysia.
The main purposes of introducing IBS at that time were to gradually reduce the dependency of foreign labours and to increase productivity. The construction process will not be affected by weather as most of the construction operation of IBS is done in factory.
History of Industrialised Building System (IBS) Present 1963 1624 Introduction of IBS in the European countries and the United States.
IBS was initiated in Malaysia when the Ministry of Housing and Local Government made visits to several European municipalities with the objective of accessing their housing development plan. It was to explore the concepts of development in these countries in further detail.
1964 Malaysia government launched a project to test the efficiency of the IBS. The key objectives looking to be fulfilled include the acceleration as well as the increase of affordable housing of substantial quality here in Malaysia.
As reported, there are 21 different manufacturers and suppliers that are promoting their components in Malaysia. An IBS centre has also been established in Jalan Chan Sow Lin, Cheras, Kuala Lumpur who responsible for implementing strategies and introducing breakthroughs in IBS technology to improve its performance and quality in the construction industry as well as to reduce dependencies of foreign labour.
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1.2 Types of Industrialised Building System (IBS) in Malaysia
Precast Concrete System
Prefabricated Timber Framing System
Precast concrete system is an industrialised building system that is widely used in Malaysia. This system requires the usage of precast concrete components such as precast concrete columns, beams, etc.
Prefabricated timber system comprises of roof trusses, timber columns and beams and timber frames. It is cost friendly, made up from multiple wooden modules, which are manufactured in plant and then delivered to building sites.
Example: Custom, Immigration & Quarantine Complex, Johor Bahru
Example: Chef Shukri’s House, Langkawi
Formwork System
Blockwork System Formwork system consists of tunnel forms, tilt-up systems, beams and columns moulding forms, permanent steelwork forms. This system is the least pre-fabricated among the IBS because it is normally involved in the site casting. It is subject to structural quality control, high-quality finishes and fast construction with less site labour and materials.
Blockwork system is basically a construction method that uses concrete and cement blocks. It includes the interlocking of masonry units and lightweight concrete blocks. Example: SMK Bandar Enstek, Negeri Sembilan
Example: PR1MA, Pahang
Steel Framing System
Innovative System Steel Frame system is basically a construction method that uses steel beams and columns, roof trusses and portal framing systems. It is a fast structural system designated for the construction of panel and continuous walls, low-rise individually standing buildings and high separating walls.
Innovative system incorporates various green elements, which are considered innovative in this system. The examples include mixture of polystyrene and concrete to produce the IBS components of a wall to enhance thermal insulation properties. Other materials introduced in IBS include gypsum, wood wool, polymer, fiberglass and aluminium-based IBS components.
Example: Telekom, Kuala Lumpur Example: Menara RKT, Kuala Lumpur
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1.3 Advantages and Disadvantages of Industrialised Building System (IBS) in Malaysia Advantages
Disadvantages
Considerable cost saving Repetitive use of formwork system and scaffolding reduces wastage after construction
High initial cost Investment in training workforce to ensure quality of workmanship and to purchase specialised machines for casting in components
Less construction time Casting of components at factory and casting of foundation in-situ can be carried out simultaneously
Low supply IBS construction has yet to be completely incorporated in local construction industry, resulting in limited number of IBS manufacturers and suppliers
Reduction of unskilled workforce Prefabrication nowadays taken place at centralised factories
Requires highly skilled labour Intensive education and training conducted to increase quality of workmanship
Better quality control Strict quality assurance and prefabrication of components at controlled environment
Restricted to large scale project Focused on mass production to reduce costs, IBS is unsuitable for small to medium scale project
Flexible construction process Construction process is not affected by weather condition as building components are manufactured under supervision earlier in factories
Rigidity of building form (Long term) Completed building structures cannot be renovated due to specific dimension of building components
1.4 Standard Design Workflow of Industralised Building System (IBS)
Design Consideration
Production Line
Delivery to Site
Assembly on Site
Completion
IBS components are initially designed based on the specification stated in MS 1064
Building components are then manufactured in modules or standard dimensions in quality controlled factories
The IBS components will be delivered to construction site in vast amount once completed.
Upon arrival, each components are carefully positioned and assembled into structures with the aid of plants and machineries.
Finishes such as plastering and painting are done to add aesthetic value to the completed unit.
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1.5 Blockwork System
1.5.1 Advantages and Disadvantages of Blockwork System
Advantages
Figure 1.5.1 Blockwork system
The blockwork system is one of six IBS systems used in Malaysia, it is a construction system which utilises concrete masonry units (CMU) and lightweight concrete blocks as the primary building block for systematic construction of low-rise structures. These blocks are now used for a wide variety of purposes such as the construction of load-bearing walls, retaining walls, partitions and foundations. The blocks are designed with features such as hollow-cores to decrease their weight and improve their insulation qualities. A standard block is 440mm x 215mm, the equivalent of 3 bricks high and 2 long, the maximum size that one person can comfortably lift. They are available in a range of widths from 50mm to 300mm. The kind of block selected for a particular application will depend on its: ● ● ● ● ●
Density. Load-bearing characteristics. Appearance. Weight and handling properties. Thermal characteristics, such as U-value or thermal mass.
Durable; Can withstand extreme temperatures and weather conditions. Higher thermal mass; Natural ability to reflect internal heat. Fire Safety; Able to keep its structural integrity during an event of a fire. Strength; Stronger compared to poured concrete when used as foundations, retaining and basement walls. Installation time; Blockwork walls can be built in a short period of time compared to use of masonry units due to its larger size.
Disadvantages Higher Cost; Concrete blocks are much more expensive compared to materials such as timber. Plain and unappealing appearance; The use of blocks can sometimes be unappealing to certain generic designs. Prone to settlement cracks; Careful installation and attention to detail is required. Low-rise limit; Blockwork system is usually implemented in low-rise structures.
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1.5.2 Types of Concrete Blocks Concrete blocks are manufactured in 2 types, namely solid block and hollow block.
Solid Block
From CKYIBStech.com
The solid concrete block is the staple for CMU, heavy and manufactured with dense aggregate. When used in large scale they produce a strong and stable structure, often seen in load bearing walls and retaining walls.
The standard hollow block sizes and designs in the market for mass usage for building load bearing walls and partition walls.
Hollow Block
From CKYIBStech.com
Standard hollow concrete blocks come in several variations, each having its distinct feature and usage. They are at least 50-percent solid and come in full or half sizes. Having a significantly lighter weight and cheaper cost, they are used in structures such as boundary fences and partition walls. The hollow cores allow rebars to be fitted to increase their strength and stability, also allowing services to be fitted through the structure.
There are also precast designs specifically meant for “column” and “beam” usage in a blockwork design. Using modular components to form the load bearing structure.
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IBS Factor (In Reference to CIS 18 : 2010)
1.6 Case Study 1.6.1 SMK Bandar Enstek, Negeri Sembilan
Component
IBS Factor
Analysis
Structural: Slab: Precast concrete slab Roof: Precast metal roof truss
0.8 1.0
Full IBS Factor Full IBS Factor
Wall: Blockwork System
0.5
Partial IBS Factor Table 1.1 IBS Factor
Types of Building Components Used Conventional Construction
Precast Components
In-situ concrete raft foundation
Prefabricated concrete staircase Prefabricated concrete slab
Project: SMK Bandar Enstek, Negeri Sembilan Construction Period: 24 months Architect: Syed Ahmad Ibrahim Associate Architects Sdn. Bhd. IBS System: Load-bearing Block Work System IBS Products / Components: Concrete Masonry Units (CMU) IBS Manufacturer: Integrated Brickwork Sdn. Bhd. Introduction SMK Bandar Enstek is a regular secondary school consisting of 11 buildings which functions as classrooms, laboratories, workshops, and administrative centres, canteen, guardhouse, and etc. The school comprises more than one thousand students and disabled students from both science and art streams. It is one of the largest projects adopting IBS system is applied as load bearing wall by incorporating the columns and beams as integral part of the wall. The entire construction saves almost 30% of the as compared to conventional with additional less foundation cost.
Stacked bond arrangement of CMU blocks which saves cost of cutting into half block. However, masonry constructed in this bond is weaker and less robust compared to running bond.
The standard sizing of the modular blocks makes the construction site and building appearance neat, organised and clean.
Prefabricated blockwork Prefabricated metal roof truss Table 1.2 Conventional construction and precast components
Sequence of Construction
Raft foundation is applied initially which also functions as large concrete slab for ground floor.
Wall is erected with CMU blocks and rebars for reinforcement. Doors and window frames are installed.
Process 1-3 are repeated until 4 floors are completed. Steel framing roof with metal decking are installed.
Upon completion, finishing is not added to remain the neat and raw appearance of the load bearing wall.
First floor in-situ concrete slab are placed on top of the walls and reinforced with rebars.
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1.6.2 The Bungalow, Kota Bahru IBS Factor (In Reference to CIS 18 : 2010)
Construction Details
Component
IBS Factor
Analysis
Roof: Prefabricated timber roof truss
1.0
Full IBS Factor
Wall: Load bearing lightweight block wall
0.8
Partial IBS Factor
Table 1.3 IBS Factor Block to foundation connection
Types of Building Components Used Conventional Construction
Precast Components
In-situ concrete raft foundation
Prefabricated blockwork
Load bearing lightweight load block wall
Prefabricated timber roof truss
Lightweight block staircase Project: The Bungalow, Kota Bahru Construction Period: 3 weeks IBS System: Load-bearing Block Work System IBS Products / Components: Lightweight Blocks Introduction The bungalow is a two-storey high and own privately. The construction of this bungalow includes the lightweight blocks, lightweight precast panel slabs and roof trusses without column. The use of IBS system in this bungalow has also proven its efficiency and competency when the whole construction process of the bungalow took only 3 weeks to be completed with a very minimal use of manpower.
Lightweight blocks are arranged in running bond. These blocks offer greater savings in time and cost. However, they are less strong compared to dense blocks.
Table 1.4 Conventional construction and precast components
Wall to slab connection
Sequence of Construction
Raft foundation is used as based due to low bearing capacity on site. It reduces differential settlement.
Wall is erected. The staircase can be built up to first floor though the main structure of the first floor structure is still not yet finished.
Once completed, lightweight floor slab panels with accurate dimension are installed to prevent material wastage.
Second floor is continued with precast lightweight concrete block wall which does not require any time for the concrete block to reach its targeted strength.
Due to integration if light weight block system with the openings in the design,construction can be carried out smoothly.
Roof truss and ceiling frame are installed, followed by roof tiles.
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CONCEPT AND FRAMEWORK
02 Concept and Framework 2.1 Proposed Industralised Building System (IBS) System The proposed IBS system to be implied to the designed 3 storey-apartment block comprises of a combination of precast concrete system, blockwork system, and steel framing system. Therefore it falls under the category of open system which allows the use of combined IBS components from different manufacturers.
Building Components
PRECAST CONCRETE COMPONENTS
PREFABRICATED COMPONENTS
-Hollow core slab -Staircase -Lintel
-Steel roof truss -Doors and Windows -Railings
CAST IN-SITU COMPONENTS
-Foundation
BLOCKWORK COMPONENTS
-CMU block wall (column and beam as integral part of wall)
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2.2.1 Cast In-Situ Strip Foundation Construction Method
Suitability
Cast In-situ Concrete
The use of a cast in-situ strip foundation is generally suited to support a structure primarily relying on load bearing walls as they follow the wall’s profile. Also the cost for using this design is relatively cheaper compared to raft foundations which require a larger amount of concrete.
Construction Materials Concrete Masonry Units (CMU), Carbon-Steel Rebars
Advantages 1. 2. 3.
Relatively cheaper compared to raft foundations due to less amount of concrete used and excavation work. Concrete curing will take a shorter time as the amount used is lesser. Strip design can be aligned to load bearing wall profiles.
Disadvantages
Carbon Steel Rebar
1. 2. 3.
Only strong enough to support structures up to 3 stories high. Require skilled labour work to build a stable foundation. Thickness of strip depends on quality of soil.
Why not raft foundation (also a type of shallow foundation)? Strip foundation is selected instead of raft foundation because it allows separate spread of footing instead of footing instead of a large spread footing which uses up more concrete to support the loads. Therefore, as compared to raft foundation, the use of strip foundation is more economical, and require less excavation as well.
Ground Slab
In-situ Concrete Foundation
Comparison between strip foundation and raft foundation.
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2.2.2 Precast Concrete Hollow Core Slab Construction Method: Precast concrete system Construction Materials: Reinforced concrete IBS Factor: 0.8 (full IBS factors) Precast concrete hollow core slabs are supported slabs of prestressed concrete members with tensile prestressing steel without any web reinforcement or masonry work. Typically used in construction of floors in multi-storey apartment building, it is an extruded concrete process that provides engineers and architects with a versatile precast concrete system for innovative construction.
Prepare concrete slabs are casted, fabricated and manufactured into various modular dimensions in the factory-controlled environment. Solid flat slab
Hollow core slab
Double Tee
Single Tee
Fabrication process
Hollow core refers to cylindrical void which run internally down the length of the precast slabs, thus reducing there weight of the slab approximately by 35%. It allows the exploitation of strength and durability of precast concrete by adding reinforcement rebars and concrete into it, whilst reducing the weight. The lower its weight, the longer its use span. Besides, the amount of concrete use is reduced, making this system both economically and ecologically sound. Prepare casting bag
Pulling and attaching prestressing wires or strands
Prestressing wires and strands
Pouring concrete and forming slab around reinforcement
Marking and cutting, notches, openings,etc
Inspection
Cutting slabs according to delivery lengths
Lifting, loading and final inspection
Delivery to site and proceed to installation
Suitability The application of strip foundation supports a limited amount of loads. Hollow core slabs with lightweight properties is chosen instead of the common precast concrete slab. As load bearing block work system is used as our building structural system, the hollow cores in the hollow core slabs enable insertion of reinforcement rebars that connects to the hollow block wall. The reinforcement rebars will then strengthen the structural integrity of these two components
Advantages 1. 2. 3. 4. 5. 6.
Low self weight Low building weight Cost saving High compressive style Less vibration than common precast concrete slab Flexibility of material (long horizontal slab) to run mechanical and electrical equipment
Disadvantages 1. 2. 3.
High capital cost Sophisticated connection works Transportation and modification limitation
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2.2.3 Precast Concrete Staircase Construction Method: Precast concrete system Construction Materials: Reinforced concrete Precast concrete staircase consist of components like staircase flight, landings and steps. All are manufactured along with the connections in the factory to ease the process of installation and assembly on site. In the precast concrete staircase fabrication process, reinforced rebars are used to strengthen the structure. The assembly and installation of precast concrete staircase usually takes place after the main superstructure, with pockets or recesses left in the supporting slabs or beams to receive stair flights.
Suitability
Fabrication Process
When comparing precast concrete staircase to timber staircase, concrete staircase is preferable in certain outdoor situations since it will stand up to rain, sun and other weather conditions. The use of prefabricated concrete staircases is more economical as the wastage of timber formworks and construction materials can be avoided, thus further saving construction costs. Precast concrete staircases are reinforced with rebars, being much stronger and able to withstand higher pressure. The time required to install the precast staircase is much shorter than cast in-situ staircase, saving time and space for installation.
Advantages 1. 2. 3. 4. 5. 6.
Using timber formwork as a mould to assemble staircase.
Cleaning the formwork and preparation for the next stage.
Reinforcement rebars are installed together with correct positioning and securing.
Pouring of concrete into mould and vibrating the concrete.
Concrete curing to form solid stair slab.
Prefabrication staircase is completed and delivered to site.
Better quality control of finished product Saving of space on site as formwork storage space Saving of time during installation process Structural materials of high strength and load-bearing capacity can be achieved. Has longer service time period and minimal maintenance A wide range of shapes and sizes are available to choose from with smooth finishing
Disadvantages 1. 2. 3.
Reduced costs of Precast Concrete is compensated by the transportation cost. Sophisticated connection works Transportation and modification limitation
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2.2.4 Prefabricated Steel Roof Truss Construction Method: IBS Prefabricated Steel Roof Truss Construction Material: Steel (Galvanised C channel roof truss) IBS Factor: 1.0 (full IBS factor)
Suitability
Prefabricated steel trusses offer a high-strength, lightweight roof system that can be installed quickly and last a lot longer than timber and require very little maintenance.
Advantages: 1. 2. 3. 4. 5.
High strength-to-weight ratio thus can withstand heavy loads. Steel is incredibly durable and requires very minimal maintenance. Complete pest resistance. Fire-resistant. Fire-retardant coatings render steel roof trusses virtually indestructible by fire. Eco-Friendliness. Steel trusses are fabricated using up to 90% recycled content and are also 100% recyclable at the end of their lifespan.
In order to reduce the structural apartment block, C-channel steel profile are chosen instead of rectangular hollow section (RHS) roof profile due to its lightweight properties. The pratt truss is the most popular steel truss since it is very economical. It includes vertical and diagonal members that slope down towards the center. Under such structural arrangement, when subject to external loads tension is induced in diagonal members while the vertical members tackle compressive forces.
Fabrication Process
Disadvantages: 1. 2. 3.
Vulnerability to corrosion. Skilled labor is required to install metal roof trusses. Higher cost compared to timber trusses.
Prefabricated steel roof truss
Feeding of metal strips by automated decoiler into rollformer.
Bending the metal sheet into C channel to form the top flange and webs for a beam.
Punching and cutting pieces accurately according to dimensions.
The material for each truss is stacked and staged on movable carts and staged for assembly after coming o the assembly line.
Assembly of truss. Webs are screwed to the top and bottom chords manually using bolts and screw guns.
Upon completion of inspection, the roof truss are ready to be shipped out to the building site.
Construction details of a roof truss
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2.2.5 Concrete Masonry Units (CMU) Blockwall Construction Method: IBS - Blockwork System Construction Materials: Concrete IBS Factor: 0.5 (Half IBS factors)
Suitability
Concrete Masonry Unit (CMU) block wall is a load bearing wall composed of standard sizes of rectangular blocks, be it hollow, solid, or U-shaped blocks. Reinforcement rebars can be placed both vertically and horizontally inside the CMU blocks to strengthen the wall and results in better structural performance. The block in which the rebar is placed must be grouted for the bars to bond the wall.
In our case, typical CMU blocks are used instead of lightweight concrete blocks because the walls are the main structural system to bear the loads, therefore CMU blocks with high compressive strength will make the walls stronger. CMU blocks are used for both exterior and interior walls to provide excellent stability and durability.
During fabrication process, different ratio of raw materials mixed or design of the blocks will lead to different compressive strength of blocks should be applied to the construction according to MS 1064. All the CMU blocks used in our designed apartment block are compiled with the following requirements:
Types of Blockwork Used
Concrete Grade: Grade 20 Mix Ratio (Cement : Sand: Aggregates): 1 : 1.5 : 3 Compressive Strength: 7.5 N/m2
200
200
Fabrication Process
400 200
Hollow Stretcher Block Used to combine masonry units to form walls.
Preparation of the raw materials such as sand, gravel, cement and stones.
Batching, crushing and mixing of raw materials.
400
200
Hollow Corner Block Used at the corner of masonry, window or door openings. Arranged in a manner that their plane end visible to the outside and other end is locked with the stretcher block.
200
400
Solid Concrete Block Used as capping for walls.
Packaging into batches.
200
400
Half Hollow Corner Block Used at the ends of masonry that connects to window or door frame.
Moulding and pressing the concrete mix.
200
Concrete curing.
200
Stocking in delivery to site.
200
200
200
400
200
400
Lintel Block
Solid Concrete Block
Used in preparation for lintel beams, serves as a masonry unit and a formwork itself.
Used to enclosed the perimeter of hollow core slabs. Sits 50% on the bond beam.
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2.3 Sequence of Construction on Site
1. Excavation and Setting out
2. Installation of Formwork
3. Foundation
After clearing the site, building is set up not less than 1.5m approximately from the plot boundary line. After setting out, foundation trenches are dug out as specified in building plan.
Erect formwork to contain and mould the wet concrete during the placing and initial hardening period.
Concrete of specific mix is prepared and poured into excavated trenches up to a specified thickness and width. The strip foundation should be at least 600mm wide and at least 200mm thick.
4. Foundation wall
5. Backfilling
6. Installation of Ground Slab
Hollow block wall is partially built from the concrete strip foundation to the height of the placement of hollow core ground floor slab. Then, reinforcement bars are added to strengthen the foundation.
The cavity between the built foundation wall is filled back with soil to a required level, by either excavated soil or ferried soil. The backfilled soil should be compacted in layers to get desired result. Water can be sprayed to dampen the soil.
Hollow core ground slabs are installed. Reinforcement bars are added and the slabs are filled with sand-cement grout.
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2.3 Sequence of Construction on Site
8. Installation of Lintel
9. Staircase
Hollow block walls are continued to be erected row by row together with the installation of prefabricated doors and windows.
Precast concrete lintels are placed on top of every door and window openings. Two layers of U-block (which act as “beam�) are assembled on the top most height of the wall before placing the first floor slab on the level.
The same process is repeated for the first and second floor subsequently. The precast concrete staircase is lifted and installed using a crane to connect the ground floor landing and the first floor landing.
10. Roof Trusses and Battens
11. Roofing
12. Finishes
The prefabricated lightweight steel roof trusses are installed on the top blockwork wall. They are supported by C-Channel and battens.
After completing the roof structure, corrugated steel decking was placed on top of it.
External works are executed like installation of door and window frames, wall paintings and coatings.
7. Installation of Wall, Door and Window
.
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2.4 Sequence of Construction of Model
1.Setting out strip foundation.
2. Building partial ground floor external wall.
3.Forming cast in situ ground floor slab.
4.Building ground floor external and internal wall.
5. Installing lintel of doors and windows.
6. Placing staircases.
7. Placing first floor hollow core slab.
8. Building first floor external and internal wall.
9. Installing lintel of doors and windows. 18
2.3 Sequence of Construction of Model
10. Placing staircases.
11. Repeat process 7-10 for second floor.
12. Placing roof trusses, battens and roofing materials.
A completed blockwork system apartment.
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TECHNICAL DRAWINGS
03 Technical Drawings 3.1 Architecture Drawings 3.1.1 Plans
GROUND FLOOR PLAN | SCALE 1:100
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FIRST FLOOR PLAN | SCALE 1:100
22
SECOND FLOOR PLAN | SCALE 1:100
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ROOF PLAN | SCALE 1:100
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3.1.2 Elevations
FRONT ELEVATION | SCALE 1:100 25
BACK ELEVATION | SCALE 1:100 26
LEFT ELEVATION | SCALE 1:100 27
RIGHT ELEVATION | SCALE 1:100 28
SECTION A-A’ | SCALE 1:100 29
SECTION B-B’ | SCALE 1:100 30
3.2 Structural Drawings 3.2.1 Structural Foundation Plan
FOUNDATION PLAN | SCALE 1:100 31
3.2.2 Structural Wall Plans (Concrete Block Arrangement)
GROUND FLOOR STRUCTURAL WALL PLAN (CONCRETE BLOCK ARRANGEMENT) | SCALE 1:100 32
FIRST FLOOR STRUCTURAL WALL PLAN (CONCRETE BLOCK ARRANGEMENT) | SCALE 1:100 33
SECOND FLOOR STRUCTURAL WALL PLAN (CONCRETE BLOCK ARRANGEMENT) | SCALE 1:100 34
3.2.2 Structural Floor Plans
GROUND FLOOR STRUCTURAL FLOOR PLAN | SCALE 1:100 35
FIRST FLOOR STRUCTURAL FLOOR PLAN | SCALE 1:100 36
SECOND FLOOR STRUCTURAL FLOOR PLAN | SCALE 1:100 37
STRUCTURAL ROOF PLAN | SCALE 1:100 38
3.3 Exploded Axonometric
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3.3 Exploded Axonometric
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SCHEDULE OF IBS SYSTEM
04 Schedule of IBS System 4.1 Concrete Masonry Units (CMU) Block wall
BLOCKWORK
COMPONENT ISOMETRIC
PLAN
QUANTITY SYSTEM
14000
1450
800
35
450
10
BLOCK WORK SYSTEM
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4.2 Precast Hollow Core Slab
SLABS
COMPONENT ISOMETRIC
PLAN
2400 SECTION
QUANTITY SYSTEM
20
68
70
40
PRECAST CONCRETE SYSTEM
43
4.4 Precast Staircase
COMPONENT
STAIRCASES
DOORS
330
ISOMETRIC
PLAN
1050 2000
900
QUANTITY SYSTEM
6 PRECAST CONCRETE SYSTEM
PREFABRICATED DOORS
44
4.5 Prefabricated Windows
WINDOWS
COMPONENT ISOMETRIC
PLAN
QUANTITY SYSTEM
500 21
750 1000 12
1500 12
PREFABRICATED WINDOWS
45
4.6 Precast Lintels
LINTEL
COMPONENT
ISOMETRIC
PLAN
800 QUANTITY COMPONENT ISOMETRIC
PLAN
1400 QUANTITY SYSTEM
PRECAST CONCRETE SYSTEM
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4.7 Prefabricated Steel Roof Trusses
47
4.7 Prefabricated Steel Roof Trusses
48
4.7 Prefabricated Steel Roof Trusses and Purlins
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CONSTRUCTION DETAILS
05 Construction Details 5.1 Cast In-Situ Strip Foundation Sectional Detail of Foundation
Strip Foundation Detail
Rebar Stiffening with Grout
Damp-Proofing Course
Hardfill Layer
The rebars inserted into the hollow cores are grouted to solidify their stability as a complete load bearing structure,
A layer of damp-proofing course is applied to building walls and floors to prevent moisture from seeping into the interior space.
The hardfill is a layer applied to ensure a stable ground condition before constructing the ground floor slab layer.
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5.2 Concrete Masonry Units (CMU) Blockwall Blockwork Wall Arrangement
2
Running bond wall arrangement Running bond, the most used bond and is composed of stretchers offset by ½ brick per course. Since there are no headers in this bond, metal are usually used. Running bond is used largely in cavity wall. Construction and veneers wall of bricks, and often in facing tile walls where the bonding may be accomplished by extra stretcher width stretcher tile.
Advantages:
1
Easy to execute Provide more strength across vertical planes than stack bond
3 4
Details of blockwork arrangement
Running bond blockwork arrangement
1. Cells containing reinforcement are filled solidly with grout. 2. Vertical reinforcement for close-end concrete masonry units can be set after the wall has been laid. 3. Horizontal reinforcement placed in bond beams 4. Metal lath mesh or wire screen placed in mortar joints under knockout bond beam courses to prevent filling of ungrouted cells.
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Grouting and Reinforcing Control joint
Joint reinforcement Joint reinforcement is used in addition to horizontal steel bar when bond beams are spaced at more than 1200mm. It is a ladder of 9 gauge (3.7mm) galvanised wire installed in the mortar joint, which positions a wire in the centre of each block faceshell. It is spaced at either a maximum of 600mm, 400mm, for stack pattern, or at 400mm seismic zones. Joint reinforcement resists wall cracking and can contribute to the horizontal steel area in the wall.
A control joint is a continuous vertical joint filled with mortar, but with a bond breaker on one side so that tensile stress cannot develop across the joint. If control joints are not provided, a concrete masonry wall may crack as it shrinks over time.
Grout & Reinforcing were required Terminate horizontal joint reinforcement at control joint Horizontal steel bars
Building paper
Grout Fill
Control Joint Joint reinforcement
Caulking Joint
Details of control joint
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Grouting and Reinforcing Grouting techniques have been developed to ensure that the walls are completely grouted. Low-lift and high-lift grouting are both traditional grouting methods, with the difference being the height of the lift. Lift five feets or less are considered as low lift, whereas lift that are higher than five feets are considered as high lift.
Stop grout one feet from top of pour to create shear key.
High lift grouting procedure
U-Block units with solid bottom at bond beam course. Grout in bond beams and reinforced vertical cells placed in top of wall after wall has been land up.
Cells containing reinforcement are filled solidly without grout, vertical cells should provide a continuous cavity free of mortar droppings.
Vertical reinforcement for closed-end concrete masonry units can be set after wall has been laid.
Cleanout openings at the base of vertically reinforced cell, 32 C. Maximum spacing for solid grouted walls to remove mortar droppings through cleanouts and verify placement and location of vertical reinforced form over openings before placing grout.
Rebar positioner, wall tie or other device to position vertical reinforcement, as required.
Option 2: Standard concrete masonry units (CMU) with cross weebs knocked out at bond beam course.
Horizontal reinforcement placed in bond beams as wall is laid up.
Metal lath, mesh or wire screen placed in mortar joints under knockout bond beam courses to prevent filling of ungrouted cells.
Note: Grout lifts not to exceed five feet.
Grouting procedures
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Wall to Wall connection Advantages Block System ● ● ● ● ● ● ●
Grout and reinforcing
Good heat and sound insulation, energy saving Easier fixing Lower density Higher thermal insulation properties Provides a suitable key for plaster and cement rendering 2 hours fire rating approved by Sirim Cheaper and simple footing along the wall is required for single storey
Block produced by Machine ● ● ● ●
Quality control Better strength No cracks Consistent size and compaction
Speed of Erecting Blockwall ● ● ●
Control joint
3 to 4 times faster than conventional method Environmentally friendly, less formworks Consistent size, less wastage
50% of interlocking to bond walls Web wall
Load Bearing Wall ● ●
Need no formwork as columns and beams are cast within blocks Save ⅔ of reinforcement compared to conventional method Control joint
Flange wall
Details of intersection walls
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Column and Beam
Concrete masonry bond beam
Concrete masonry beams units
bond
Reinforcing bar
Bond beam reinforcing
610 x 610 corner bar at intersection
Control joint
Hollow core stretcher block
Encastre concrete column Vertical reinforcement
Details of column and beam
Bond beam plan details
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Bond beam at intersecting wall
Length as required to develop reinforcement
Grout and reinforcing as required
Flange wall
Rake out mortar for control joint
Knock out face shell of bond beam unit for continuous grout and reinforcement
Web wall Rake out mortar for control joint
Bond beams at intersecting walls
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5.3 Precast Concrete Hollow Core Slab On-site Construction Process 1. All transported precast concrete slabs are marked by an official label meeting standard requirement. It is usually inspected and checked to verify the quality and quantity of all transported items prior to unloading them.
Sectional view of hollow core slab
Legend 1. 50mm structural concrete screed 2. Mesh reinforcement 3. Filling with sand-cement grout
2. Unloading and hoisting of transported precast hollow core slabs should be conducted using a hoisting traverse, which consists of a lifting beam with two hoisting grippers. 3. All the unloaded hollow core slabs will be stored at the interim storage on site. In case if the site does not have interim storage, they will be usually placed at a higher leveled site to prevent mixing from the current construction materials. 4. Hollow core slabs are then installed on a levelling neoprene strip, fastened to the bearing structure 5. Different curvatures of adjacent slabs may occur of many influences such as improper storage of slabs, transportation and different length of slabs. Clamping device will be used to equalize the curvature occured on the slabs. 6. The quantity of slabs needed and its construction method are usually stated at the drawing production stage. Their locations on the floor are marked and concreting peculiarities shall be indicated. 7. The installation joints that are between the slabs and the end of slabs should be filled up with fine aggregate concrete to make sure that it is perfectly covered.
Bond beams at intersecting walls
Legend 1. 50mm structural concrete screed with mesh reinforcement applied to the rough top of hollow core slab to form a composite structural unit. 2. Adjacent hollow core slabs are locked together by grout keys.
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Slab to beam connection
Slab to internal beam connection
Connection of different levels of slab
Connection of different levels of slab
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Slab to external wall connection
This detail shows a precast concrete plank bearing at an exterior of CMU wall. The wall has horizontal joint reinforcement at 16’’ o.c. vertically. The plank has reinforcement and grout at the keyways, and the floor bears on a concrete masonry (CMU) bond beam. The wall is grouted and reinforced vertically as required, and the bars are lapped to achieve sufficient development strength per structural design. The brick veneer is not shown for for clarity.
Legend 1. Grout and vertical reinforcing as required 2. Lap vertical bar splice above slab level 3. Horizontal joint reinforcement 4. Precast hollow concrete slab to bear on bond beam 5. 2’ - 0’’ horiz x 2’ -0’’ vert dowels and grout as slab keyways 6. 50mm structural concrete screed 7. Cavity filled solidly with grout 8. 3’’ min bearing and bearing strip 9. Solid CMU “soaped” set in mortar before grout is poured 10. Bond beam 11. Filled joint solidly with grout 12. Reinforcing bar placed at specified intervals 13. Fill cell solidly with grout
Slab to external wall connection
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Slab to internal wall connection
This detail shows a precast concrete plank bearing at an interior CMU wall. The wall has horizontal joint reinforcement at 16� o.c. vertically. The plank has continuous reinforcement and grout at the keyways, and the floor bears on an interior CMU bond beam. The wall is grouted and reinforced vertically as required, and the bars are lapped to achieve sufficient development strength per structural design.
Legend 1. Lap vertical bar splice above slab level 2. Horizontal joint reinforcement 3. Precast hollow concrete slab to bear on bond beam 4. Hollow core blockwork 5. 50mm structural concrete screed 6. Cell filled solidly with grout 7. Reinforcing bar in keyways 8. 3� min bearing and bearing strip 9. Bond beam 10. Grout and vertical reinforcing 11. Reinforcing bar placed at specified intervals
Slab to internal wall connection
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5.4 Precast Concrete Staircase
Precast stairs Blockwork wall
Precast landing
Sleeve
Slab Non-shrink, non metallic grout
Structural shim packer Plate
Bar embedded
Landing to wall connection
Stairs to floor connection
Precast landing
Precast stairs Bent plate
Precast stairs
Plate
Landing to down riser connection
Precast landing
Plate
Landing to up riser connection
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5.5 Prefabricated Steel Roof Truss
Prefabricated C-channel roof truss Top Chord Steel bolt Bolt
Web Joint Steel gusset plate
Concrete fill
Apex Joint Reinforced steel bar Angle steel plate
U-Block (Bond beam) Bottom Chord Steel roof truss to block wall connection
Web Joint
Self drilling screws Heel Joint
Prefabricated C-channel roof truss
Reinforcement bar
Concrete fill
U-Block (Bond beam) Bearing stiffener
Pratt roof truss joint connection Cross section of steel roof truss to block wall connection
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5.5 Prefabricated Steel Roof Truss
Cladding to batten connection (crest fixed) Cladding to batten load transfer through self-drilling screw 6mm thick aluminium roof decking Corrugated roofing
100mm thick rockwoll insulation layer
Roof batten
Aluminium netting
Vapor barrier (DPM)
Batten to truss connection Cladding to batten load transfer through self-drilling screw
Steel roof truss
Rafter
Batten to roofing and truss connection
Metal roof layering
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5.6 Doors and Windows
Elevation view of door connection
A lintel is a structure horizontal block that spans the space or openings between two vertical supports. Lintel should be installed with a minimum end bearing of 150mm, bedded on mortar and levelled along its length and across its width. Door and window connection
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5.7 Ceiling Conventional ceiling connection The lateral loads in the roof-ceiling are based on the mass of roof-ceiling assembly and a portion of the mass of the wall in the story immediately below the roof.
Ceiling connection
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5.8 Toilet Pod
Rooftop Panel
Toilet Pod Toilet pod is a pre-engineer, pre-fabricated, pre-fitted bathroom and is delivery ready for installation with “Plug and Play” concept that meant for fast-paced construction industry.
Plumbing & Electrical Integrated, pretested plumbing and electric, code compliant and ready for final hookup.
Advantages: ● ● ●
Interior Wall Completely finished interior clean and ready to use.
● ●
Faster construction programmes for accelerated occupation Cost savings over traditional on-site installation Elimination of many-on-site health and safety issues Highest standards of quality control Minimal on-site skill labour required
Waterproof Wall Board Completely finished interior clean and ready to use.
Floor Tiles Waterproof, thin profile subfloor supports floor finish while providing a seamless transition to the adjoining floor.
Toilet pod detail
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5.9 Finishes Wall finishes layering:
Blockwall
Plastering Skim Coat
Colour Paint
On-site construction process:
Make sure that the block wall is completely set up.
Blocks are plastered aggregate concrete.
Skim coat is applied for a smoother surface.
Colour paint is applied as finishing for aesthetic purpose.
over
with
fine
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IBS SCORE CALCULATION
06 IBS Score Calculation
208.4m2
0.8
(208.4 / 850.6) = 0.25
0.25 x 0.8 x 50 = 10.0
208.4m2
0.8
(208.4 / 850.6) = 0.25
0.25 x 0.8 x 50 = 10.0
208.4m2
0.8
(208.4 / 850.6) = 0.25
0.25 x 0.8 x 50 = 10.0
225.4m2
1.0
(225.4 / 850.6) = 0.26
0.26 x 1.0 x 50 = 13.0
850.6m2
1.01 (≃1.00)
43.0
86.5m x 3 = 259.5 64.7m x 3 = 194.1
259.5 / 453.6 = 0.57 194.1 / 453.6 = 0.43
0.57 x 0.5 x 20 = 5.7 0.43 x 0.5 x 20 = 4.3
453.6m2
0.5
1.0
10
198/198 x100%=100%
8 4
42/42 x 100% = 100%
4
45/45 x 100% = 100%
4
3/3 x 100% = 100%
2
3/3 x100% = 100%
2
3/3 x100% = 100%
2 26 79
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CONCLUSION
07 Conclusion With an IBS score of 79%, the 3-storey apartment block has reached an optimum use of IBS system. This implies a clear understanding of components that manufactured in a controlled environment has been applied to the design of the building. The IBS systems applied include precast hollow core slabs, block work, prefabricated steel roof trusses, doors and windows which have successfully contributed to our IBS score. Throughout this project, we have managed to understand the advantages and suitability of this building system in modern construction. We now have more insight regarding the role and importance of this system in the construction evolution through various research studies, understandings and investigations. We have managed to analyze the types of IBS construction methods and understand the construction method of this system. We were able to propose an apartment that mostly composed of IBS systems which demonstrates a comprehensive understanding of the construction system. We have managed to implement appropriate IBS components in the production of a model in an apartment building. Through the model making, we have understood more about IBS fabrication, construction process, installation method, practicality and IBS score calculation method.
Prefabricated Steel Purlin
Prefabricated Doors
Prefabricated Railings
Precast Concrete Slab
Prefabricated Steel Roof Truss
CMU Blockwork Wall
In summary, the IBS system not just reduces construction time, total cost and dependency on foreign workers, but also increases quality of buildings, promotes safe and systematic factory working environment, as well as providing a cleaner and neate site. This system has also contributed to the growing demand for affordable accommodation yet allows maximum efficiency within minimum time span and low budget range. Thus, it has solved concerns regarding high construction costs, low production rates, quality effectiveness, and productivity of the construction.
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REFERENCES
08 References 1. Cavity Walls. (2019). Retrieved May 7, 2019 from https://masonryadvisorycouncil.org/wp-content/uploads/2016/05/cavitywalls.pdf 2. Concrete Block Walls. (2019). Retrieved May 7, 2019 from https://www.mclendons.com/tips-projects/diy-how-tos/patios-and-walls/Concrete-Block-Walls 3. Floors screeds. (2019). Retrieved May 7, 2019 from https://www.concretecentre.com/Building-Elements/Floors/Floor-Screeds.aspx 4. Handling setting (2019). Retrieved May 7, 2019 from http://www.midsouthprestress.com/product-data/handlingsetting.pdf 5. Hollowcore Concrete: Concrete Hollow Core Floor Slabs (2019). Retrieved May 7, 2019 from http://www.hollowcore.com.au/hollow_core_floor_slabs.php 6. IG Lintels | Lintel Installation Guide (2019). Retrieved May 7, 2019 from http://iglintels.com/technical-information/lintel-installation-guide/ 7. Kamjan R. Ladder marches and platforms (2019). Retrieved May 7, 2019 from http://www.kamenschik.com/en/ladder-marches-platforms.html 8. Prefabricated reinforced concrete stairs - stair kosour (2019). Retrieved May 7, 2019 from https://sites.google.com/site/stairkosour/prefabricated-reinforced-concrete-stairs// 9. Strip foundation (2019). Retrieved May 7, 2019 from http://www.monitor.co.ug/Magazines/HomesandProperty/-building-strip-foundation/689858-3868220-1197kpr/index.html 10. Concrete blocks (n.d). How Products Are Made. Retrieved May 7, 2019 from http://www.madehow.com/Volume-3/Concrete-Block.html 11. Anupoju.S (n.d). Types of Concrete Blocks or Concrete Masonry Units Used in Construction. Retrieved May 7, 2019 from https://theconstructor.org/building/types-concrete-blocks-masonry-units/12752/ 12. Lawsons (n.d). 215mm Hollow 7N Concrete Block. Retrieved May 7, 2019 from https://www.lawsons.co.uk/product/215mm-hollow-7n-concrete-block/h00001130 13. Daily Express (2017). IBS Construction from now. Property Hunter. Retrieved May 7, 2019 from https://www.propertyhunter.com.my/news/2017/10/4164/sabah/ibs-construction-method-from-now 14. Storey. M (2017). Industrialized Building System. Retrieved May 7, 2019 from https://www.scribd.com/document/367790101/Project-1-Industrialized-Building-System 15. Running Bond vs Stack Bond: Pros and Cons. Retrieved May 7, 2019 from https://www.doityourself.com/stry/running-bond-vs-stack-bond-pros-and-cons 16. Hamakareem.M (n.d). What are the types of structural steel frame system. Retrieved May 7, 2019 from https://www.doityourself.com/stry/running-bond-vs-stack-bond-pros-and-cons
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17. Wiseowl, (n.d). Timber frame for a Straw Bale Home. Retrieved May 7, 2019 from https://www.wiseowljoinery.com/wp-content/uploads/2018/01/frame-lg.jpg 18. CNME, (n.d). Economic Tunnel Formwork System / Steel Formwork System Powder Coated Surface Treatment. (2019). Retrieved May 7, 2019 from http://www.formworkscaffoldingsystems.com/sale-9582691-economic-tunnel-formwork-system-steel-formwork-system-powder-coated-surface-treatment.html 19. Digging Strip Foundations. (2015, September 01). Retrieved May 7, 2019, from http://www.houseselfbuild.com/digging-strip-foundations/
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