CONSTRUCTION TECHNOLOGY

Dr Adewale Abimbola, FHEA, GMICE.

www.edulibrary.co.uk

​

Aim & Objectives

Aim: Traditional Construction: Floor, Wall, & Roof.

Objectives: At the end of the lesson, the students should be able to:

• a) Explain the key techniques and materials used in traditional construction methods.
• b) Communicate technical construction concepts and details through diagrams and discussion.

- A variety of construction methods are available for low-rise dwellings and structures.�- Method selection influences cost, speed, durability, and sustainability of the project.

Forms of Low-rise Construction

Table 1. The three main construction methods for low-rise structures

• Each construction method presents distinct advantages and considerations in project design
• Choice of method can impact energy efficiency, maintenance needs, and adaptability of the building.

Floors

4

Main Functions of Floors

1. Physical barrier
2. Bear required loads
3. Control sound transmission
4. Reduce thermal transmittance
5. Prevent spread and penetration of fire
6. Resist impact
7. Accommodate openings and penetrations
8. Reduce deflection to a minimum
9. Support other parts of the structure

Solid Floor Construction

• Traditional used for outbuildings such as washrooms.
• Provide good stability and load-bearing capacity.
• Typically constructed with concrete slab on compacted hardcore.
• Became more popular after WWII because of restriction on imported timbers used for timber floors.
• Damp-proof membrane (DPM) were initially absent. Alternatives such as clay tiles and quarry tiles were used.
• Bitumen coating may be have been applied before laying the floor finish to prevent moisture ingress.
• Clay tiles allow the floor to breathe and any moisture to escape.

Figure 2. A concrete floor 1960s – 1990s (University of the West of England, 2009a)

Figure 1. A concrete floor 1950s (University of the West of England, 2009a)

Solid Floor Construction

Problems:

• Prone to cracking and sinking over time.
• Poor thermal insulation properties.
• Mould growth against walls at floor level.

Figure 2. A concrete floor 1960s – 1990s (University of the West of England, 2009a)

Suspended Floor Construction

• Constructed from timber joists (100mm X 50mm at 400mm c/c) and floorboards.
• Popular during the Victorian era (1839-1901).
• Supported by load-bearing external/internal walls.
• Often used in older properties and some modern timber-frame buildings.
• Require adequate ventilation beneath to prevent damp issues. This is achieved by using honeycomb walls.
• The floor joists rests upon the wall plates tied onto the honeycomb walls. Slates were later used to protect the joist and prevent rising damp.

Figure 3. A typical suspended timber floor (University of the West of England, 2009a)

Figure 4. The 1920s improvement to suspended timber floor (University of the West of England, 2009a)

Suspended Floor Construction

Problems:

• Vulnerability to damp and wood-boring insects.
• Potential for squeaking and movement.
• Limited span capabilities.

Figure 4. The 1920s improvement to suspended timber floor (University of the West of England, 2009a)

Solutions:

• Use of treated timber and improved ventilation.
• Installation of additional support or steel reinforcement.

Intermediate Floor Construction

• Generally refer to floors between ground and upper levels.
• Traditionally constructed using timber joists.
• Supported by the internal walls of the building.
• Herringbone strutting provided lateral restraint (Fig. 5). Recommended at 1.8 m intervals.
• Intermediate floors span the shortest distance.

Figure 5. An intermediate floor (DukeLewis87, 2013).

Figure 6. Late 19^th century upper floor construction (University of the West of England, 2009c)

Intermediate Floor Construction

Problems:

• Poor sound insulation between storeys.
• Potential for vibration and movement.
• Difficulties in routing services.

Solutions:

• Use of engineered joists for greater strength and span.
• Incorporation of sound insulation materials.
• Design for easy access to services.

Figure 5. Figure 1. An intermediate floor (DukeLewis87, 2013).

Figure 7. 1930s upper floor construction (University of the West of England, 2009b)

Group-assessment Task

Your team is tasked with designing and specifying the traditional timber suspended ground floor for a new low-rise domestic building in the UK. The client requires the floor system to meet modern building regulations for durability, ventilation, and energy efficiency.

In groups, review the following construction aspects and discuss answers with reference to UK best practice and building standards.

Each group presents their findings, including diagrams or sketches where useful.

​

1. What is a traditional timber floor?

• Describe its main components (joists, wall plates, sleeper walls, floorboards, insulation, and airbricks).
• Briefly explain its typical use for ground or upper floors in UK residential buildings.

2. What are typical sizes and grades for joists and floorboards?

• Research suitable timber grades (e.g., C16, C24) and common cross-sectional sizes for joists and floorboards.
• Discuss/show span and spacing standards.

3. How is ventilation and damp-proofing achieved in timber floors?

• Explain the required void beneath the floor and the positioning of airbricks.
• Discuss the use of damp proof course (DPC) and best practice in avoiding moisture problems.

4. How is strutting or bridging used to strengthen floor joists?

• Describe why and where strutting or herringbone bridging is installed.
• Illustrate the impact on floor performance.

Walls

13

Main Functions of Walls

1. Strength
2. Stability
3. Weather exclusion
4. Thermal Insulation
5. Sound Insulation
6. Durability
7. Fire resistance
8. Appearance

The traditional wall construction that will be considered are: solid, cavity, and framed.

​

Part of a cavity wall with the internal skin removed to expose the Insulation

Solid Wall Construction

Historical context:

• Earliest form of wall construction in the UK.
• Common from ancient times through the early 20th century.
• The sedimentary stone/rock, which includes limestone and sandstone, accounts for most of the stone used for building in the UK.

Characteristics:

• Single layer of material, typically stone, brick or blockwork. Usually 200 mm thick for a 1 brick wall. It could exceed 325 mm for stone wall.
• No cavity or insulation within the wall.
• For weather proof, the outside of the wall can be rendered or finished in another material.

Figure 8. Evolution of external walls (University of the West of England, 2009a)

Solid Wall Construction

Examples in the UK:

• Medieval castles (e.g., Tower of London, Cardiff Castle).
• Georgian townhouses.
• Victorian terraced houses.

Advantages:

• Durability and strength.
• Thermal mass for temperature regulation.

Disadvantages:

• Poor insulation properties.
• Susceptible to damp issues.

Figure 8. Evolution of external walls (University of the West of England, 2009a)

Cavity External Wall Construction

Historical context:

• Introduced in the late 19th century to prevent penetrating damp.
• Became standard practice in the 1920s and 1930s.
• Early use did not have insulation, just two skins of brickwork. Blockwork was later used for the inner leaf because of the lighter weight and better insulation properties.

Characteristics:

• Two layers of material with air gap between.
• Often brick outer leaf and block inner leaf.
• Cavity typically 50-100mm wide.

Figure 2. Traditional cavity wall (University of the West of England, 2009a)

Cavity External Wall Construction

Examples in the UK:

• Interwar semi-detached houses.
• Post-war council estates.

Advantages:

• Improved insulation and damp protection.
• Lighter construction compared to solid walls.

Disadvantages:

• Potential for thermal bridging through poorly installed or deteriorated/uninsulated cavities.
• Cavity wall tie failure in older buildings.

Figure 2. Traditional cavity wall (University of the West of England, 2009a)

Traditional Internal Wall Construction

Solid Internal Walls:

• Typically constructed using brick or blockwork.

• Often used for load-bearing walls in older properties.

• No major requirement for temperature efficiency as required by external walls.

• Generally thicker than modern partition walls.

• Older lime plasters used on the walls detach easily as they are not long-lasting.

• Offered high thermal mass, helping to regulate indoor temperatures.

• Mould can develop if the DPC is flawed.

Figure 9. Internal walls (H+H UK Limited, 2022)

Traditional Solid Internal Wall Construction

Problems encountered:

• Prone to damp issues, especially rising damp
• Can be structurally weak if mortar deteriorates.

Figure 9. Internal walls (H+H UK Limited, 2022)

Solutions:

• Careful repointing with appropriate mortar.
• Use of breathable materials for any retrofitted insulation.
• Installation of chemical damp-proof courses where appropriate.

Traditional Internal Wall Construction

Hollow Internal Walls:

• Commonly used in residential construction since the 19th century.

• Consisted of vertical timber studs fixed between floor and ceiling.

• Typically used 100 x 50mm softwood timbers for studs.

• Studs usually spaced at 400mm or 600mm centres.

• Often incorporated a timber sole plate at the bottom and head plate at the top.

• Traditionally infilled with lath and plaster for wall surfaces.

• Vulnerable to damp and wood-boring insects if inadequately treated or ventilated.

Figure 10. Lath and plaster for interior wall finish (Designing Buildings Ltd., 2022)

• Traditionally infilled with lath and plaster for wall surfaces

• Later versions used plasterboard sheets nailed directly to the studs

Traditional Hollow Internal Wall Construction

Problems encountered:

• Susceptible to movement and cracking if not properly constructed.
• Vulnerable to damp and wood-boring insects if inadequately treated.
• Limited sound insulation compared to solid walls.
• Difficulty in hanging heavy items between studs.

Figure 11. Dry lining of walls (IBB.uk, 2023)

Solutions:

• Installation of loadbearing wall boards for easier fixture mounting
• Application of vapour barriers and proper ventilation to prevent damp issues
• Use of fire-resistant plasterboard to improve fire safety

Group-assessment Task

Your group has been asked to advise on the design and construction of the external and internal walls of a new low-rise building in the UK using traditional brick-and-block methods.

In groups, review the following construction aspects and discuss answers with reference to UK best practice and building standards.

Each group presents their findings, including diagrams or sketches where useful.

​

1. What is a traditional wall in UK construction?

• Define its basic components (outer leaf, inner leaf, cavity, wall ties).
• Identify its structural role in supporting loads and enclosing the building.

2. What are typical sizes and materials for a traditional wall?

• Specify standard brick and block dimensions.
• Discuss common cavity sizes and insulation choices.

3. How is a damp-proof course installed and why is it important?

• Explain the placement of a DPC and the consequences of poor installation.

4. How are openings for doors and windows typically formed?

• Describe the use of lintels and the method for safely creating and supporting these openings.

Roofs

24

1. Durable against the adverse effects of various agencies such as wind, rain, sun, etc.
2. Desirable insulation against sound and heat.
3. Structurally stable and sound.
4. Be well-drained.
5. Efficient water-proofing arrangements.
6. Fire resistance.

Main Design Requirements of Roofs

Figure 12. Roof structure (University of the West of England, 2009b)

Traditional Roof Construction – Onsite Assembly

Historical context:

• Used since medieval times.
• Common method until mid-20th century.

Characteristics:

• Rafters cut and assembled on-site.
• Typically uses larger timber sections.
• Allows for complex roof shapes.

Examples in the UK:

• Tudor and Elizabethan manor houses.
• Victorian terraced houses.

Figure 12. Roof structure (University of the West of England, 2009b)

Advantages:

• Adaptable for bespoke designs.
• Creates usable loft space.

Disadvantages:

• Labour-intensive.
• Requires skilled carpenters.

Traditional Roof Construction - Roof Truss

Historical context:

• Introduced in the 1960s.
• Became widespread in the 1970s and 1980s.

Characteristics:

• Prefabricated off-site.
• Triangular structure.
• Various designs available (e.g., Fink, King Post).

Advantages:

• Quick installation.
• Cost-effective.
• Consistent quality.

Figure 13. Types of roof truss (RMIT University, no date)

Disadvantages:

• Limited loft space in standard designs.
• Less flexibility for alterations.

Ties in tension (in blue), compression and struts in compression (in red)

ROOF FINISHES

SLATE

Historical context:

• Used since Roman times.
• Peak popularity in Victorian era.

Characteristics:

• Durable and long-lasting.
• Often from Welsh quarries.

Examples:

• Victorian public buildings.
• Traditional cottages in Wales and Scotland.

Historical context:

• Used in areas with local stone availability.
• Common in medieval and early modern periods.
• Limestone, and quartzite are commonly used for their waterproof, anti-freeze, and durable properties

Characteristics:

• Heavy, requiring robust support structure.
• Often seen in Cotswold region.

Examples:

• Cotswold stone roofs.
• Yorkshire stone roofs.

STONE

ROOF FINISHES

CLAY TILES

Historical context:

• Used since Roman times.
• Widespread from 16th century onwards.

Characteristics:

• Various styles (e.g., plain, pantiles).
• Often red or orange in colour.

Examples:

• Tudor and Elizabethan buildings
• Kent peg tile roofs.

Historical context:

• Ancient roofing method.
• Common in rural areas until 19th century.

Characteristics:

• Made from straw or reed.
• Requires regular maintenance.

Examples:

• Traditional cottages in Devon and Dorset.
• Historic buildings in East Anglia.

THATCH

ROOF FINISHES

Historical context:

• Gained popularity in 20th century.
• Often used for industrial and agricultural buildings.

Characteristics:

• Lightweight and durable.
• Materials include zinc, copper, and steel.
• Susceptible to rust.

Examples:

• Modern agricultural barns.
• Contemporary architectural designs.��

Metal Sheet:

Group-assessment Task

Your team has been commissioned to oversee the roof construction of a new low-rise residential building in a Welsh village. The design calls for a pitched roof using conventional materials and methods.

In groups, review the following construction aspects and discuss answers with reference to UK best practice and building standards.

Each group presents their findings, including diagrams or sketches where useful.

​

1. What is a gable wall?

Define the role and structural importance of a gable wall in a traditional pitched roof.

2. What size should a wall plate be?

Research and propose an appropriate cross-sectional size for a timber wall plate based on typical domestic construction.

3. What size is a ridge board?

Recommend a standard ridge board dimension for residential pitched roofs, considering factors such as span and loading.

4. How are purlins installed into the gable walls?

Describe the method for securely installing purlins into gable walls, including support details and fixing requirements.

Reference/Bibliography

Bock, G. H. (2020) Making sense of metal windows in historic buildings. Available at: https://www.traditionalbuilding.com/product-report/metal-windows-in-historic-buildings (Accessed: 21 September 2024)

Designing Buildings Ltd. (2022) Lath and plaster. Available at: https://www.designingbuildings.co.uk/wiki/Lath_and_plaster (Accessed: 21 September 2024)

DuleLewis87 (2013) Carpentry. Available at: https://www.diychatroom.com/threads/length-for-quick-question.183139/ (Accessed: 21 September 2024)

H+H UK Limited (2022) Internal walls: partition walls. Available at: https://www.hhcelcon.co.uk/products-applications/applications/internal-walls-partition-walls (Accessed: 21 September 2024)

IBB.uk (2023) Dry Lining Guide - walls and ceilings. Available at: https://www.ibb.uk/advice/post/dry-lining-guide-walls-and-ceilings (Accessed: 21 September 2024)

Legacy Post & Beam (2024) Living spaces. Available at: https://legacypostandbeam.com/living-spaces/ (Accessed: 14 September 2024)

Non Standard House Construction (2017) Airey house information – structure & asbestos. Available at: https://nonstandardhouse.com/airey-house/ (Accessed: 14 September 2024)

Norwood, G. (2012) Post & beam explained. Available at: https://www.self-build.co.uk/post-beam-explained/ (Accessed: 14 September 2024)

Pearson (2017) BTEC national construction student book. London: Pearson.

RMIT University (no date) Roof trusses. Available at: https://emedia.rmit.edu.au/dlsweb/Toolbox/buildright/content/bcgbc4010a/04_struct_members/04_roof_trusses/page_005.htm (Accessed: 14 September 2024)

The Past Ltd (2024) Cruck construction: an uncouth and rudimentary building technique?. Available at:

https://the-past.com/feature/cruck-construction-an-uncouth-and-rudimentary-building-technique/ (Accessed: 14 September 2024)

University of the West of England (2009a) Evolution of building elements. Available at: https://fet.uwe.ac.uk/conweb/house_ages/elements/section2.htm (Accessed: 14 September 2024)

University of the West of England (2009b) Roof structure. Available at: https://fet.uwe.ac.uk/conweb/house_ages/elements/section5.htm (Accessed: 14 September 2024)

University of the West of England (2009c) Upper floors. Available at: https://fet.uwe.ac.uk/conweb/house_ages/elements/section4.htm (Accessed: 21 September 2024)

​

​

​

​