Historical Context and Manufacturing Details

The Cussins house, a notable example of post-war British architecture, was manufactured by Cussins Ltd. These properties were constructed between 1945 and 1946, a period marked by a significant housing shortage in the UK. The urgency to provide homes for returning soldiers and their families led to the development of various system-built properties, including the Cussins house. Approximately 3,500 of these houses were built, primarily in suburban areas across the UK.

Cussins Ltd, the manufacturer, collaborated with designers to create a robust and efficient housing solution. These houses are also known by alternative names such as Cornes, Cornes Cussins, and Cussins Cornes. The design and construction of these homes reflect the technological advancements and material constraints of the post-war era.

Identification Characteristics

Identifying a Cussins house is relatively straightforward due to its distinctive features. These properties are typically two-storey semi-detached houses with a medium pitch gable roof. The roofs are covered with either clay pantiles or interlocking concrete tiles, providing a durable and weather-resistant finish.

The external walls of Cussins houses vary in construction. They can be made of clay-slip-faced panels arranged in an unbonded pattern, rendered PRC (Precast Reinforced Concrete) panels, or brick throughout. The variation in window sizes adds to the unique aesthetic of these homes. Additionally, a single-storey brick outhouse is often attached to the gable wall, and a flat canopy typically covers the front door.

Construction Details

Substructure

The substructure of a Cussins house consists of concrete strip footings and a brick-faced reinforced concrete (RC) edge beam. A damp-proof course (DPC) is also included to prevent moisture from rising through the structure.

Main Frame

The main frame is a critical component of the Cussins house, providing structural integrity. It comprises nine double RSC (Rolled Steel Channel) stanchions, each forming a hollow box. The frame also includes twelve RSJ (Rolled Steel Joist) perimeter beams, six RSJ floor and ceiling support beams, one RSJ trimmer beam, and RSC horizontal and vertical secondary framing. The frame members are connected using Kariscol joints, which are known for their strength and durability. The primary frame is coated with red oxide paint for protection, while the secondary frame is coated with black bituminous paint.

External Walls

The external walls of Cussins houses are constructed using PRC panels faced with clay slips arranged in an unbonded pattern. These panels are tied back to mild steel (MS) bars, creating a cavity that is filled with woodwool slabs for insulation. Some variants of the Cussins house feature brick external walls or rendered PRC panels.

Separating Walls and Partitions

The separating wall between semi-detached units is typically a 9-inch brick wall. Internal partitions are made of timber stud lined with plasterboard, providing a lightweight and flexible solution for interior walls.

Floors

The ground floor of a Cussins house is constructed with asphalt on concrete, ensuring a solid and durable base. The first floor features tongue-and-groove (T&G) boarding on timber joists, providing a stable and resilient surface.

Ceilings and Roof

Ceilings in Cussins houses are made of plasterboard, offering a smooth and clean finish. The roof structure includes timber rafters, bituminous felt, timber battens, and interlocking concrete tiles. Some variants may have a clay pantile roof cover.

Typical Hazards and Risks

While Cussins houses were built to address the immediate post-war housing crisis, they are not without their issues. Understanding these potential hazards and risks is crucial for prospective buyers and investors.

Corrosion

One of the primary concerns with Cussins houses is the corrosion of metal components. Minor corrosion can occur in the hollow box RSC stanchions, particularly at the bases and below the DPC. RSJ ground floor beams and RSC secondary framing may also exhibit superficial corrosion. Additionally, the reinforcement in PRC panels, restraining hooks, associated rods, and spacers can corrode over time.

Structural Issues

Displacement of PRC panels and cracking of mortar joints between these panels are common issues. Brickwork may also crack, and render can detach from the external walls. These structural problems can compromise the integrity of the building and require prompt attention.

Moisture and Damp

Due to the age of these properties, moisture ingress and dampness can be significant concerns. The effectiveness of the original DPC may have diminished over time, leading to rising damp. Additionally, the cavity insulation (woodwool slabs) may have degraded, reducing its effectiveness and potentially contributing to damp issues.

Defective Premises Act Considerations

The Defective Premises Act 1972 imposes a duty on builders, developers, and landlords to ensure that properties are constructed and maintained to a reasonable standard. While Cussins houses were built to address an urgent housing need, some of the construction methods and materials used may not meet modern standards.

Cussins houses are not universally classified as defective under the Defective Premises Act. However, the issues outlined above, such as corrosion, structural problems, and dampness, can lead to significant defects if not addressed. It is essential for buyers and investors to conduct thorough surveys and assessments to identify and rectify any potential issues.

Inspection Guide for Surveyors

When inspecting a Cussins house, surveyors should pay close attention to several key areas to identify potential issues and assess the overall condition of the property.

External Inspection

1. Roof: Check the condition of the clay pantiles or interlocking concrete tiles. Look for any signs of damage, missing tiles, or wear and tear. Inspect the flat canopy over the front door for any signs of deterioration.

2. Walls: Examine the external walls for signs of cracking, displacement of PRC panels, and detachment of render. Pay particular attention to the mortar joints between PRC panels and the condition of the brickwork.

3. Outhouse: Inspect the single-storey brick outhouse attached to the gable wall. Check for any structural issues, dampness, or signs of neglect.

Internal Inspection

1. Substructure: Assess the condition of the concrete strip footings and the brick-faced RC edge beam. Look for any signs of settlement or movement.

2. Main Frame: Inspect the RSC stanchions, RSJ beams, and secondary framing for signs of corrosion. Pay particular attention to the bases of the stanchions and areas below the DPC.

3. Floors: Check the ground floor for any signs of dampness or damage to the asphalt and concrete. Inspect the first floor for any issues with the T&G boarding and timber joists.

4. Walls and Partitions: Examine the separating wall and internal partitions for any signs of cracking, movement, or dampness. Check the condition of the plasterboard lining.

5. Ceilings and Roof: Inspect the plasterboard ceilings for any signs of sagging, cracking, or water damage. Assess the condition of the timber rafters, bituminous felt, and timber battens in the roof structure.

Additional Considerations

1. Dampness: Use a moisture meter to check for signs of dampness in walls, floors, and ceilings. Pay particular attention to areas around the DPC and cavity insulation.

2. Insulation: Assess the condition of the woodwool slab cavity insulation. Degraded insulation can contribute to dampness and reduce the energy efficiency of the property.

3. Services: Check the condition of the plumbing, electrical, and heating systems. Ensure that they meet current safety standards and are in good working order.

Typical Defects and Maintenance Tips

Understanding the typical defects associated with Cussins houses can help buyers and investors make informed decisions and plan for necessary maintenance and repairs.

Corrosion

Corrosion of metal components is a common issue in Cussins houses. Regular inspections and maintenance can help mitigate this problem. Applying protective coatings, such as red oxide paint or black bituminous paint, can help prevent further corrosion. In severe cases, replacing corroded components may be necessary.

Structural Repairs

Addressing structural issues, such as displacement of PRC panels and cracking of mortar joints, is crucial for maintaining the integrity of the property. Repointing mortar joints, repairing or replacing damaged panels, and reinforcing brickwork can help address these issues. Consulting a structural engineer for a thorough assessment and repair plan is recommended.

Dampness and Insulation

Addressing dampness and improving insulation can enhance the comfort and energy efficiency of a Cussins house. Replacing or repairing the DPC, improving cavity insulation, and addressing any sources of moisture ingress can help mitigate damp issues. Installing modern insulation materials can also improve the thermal performance of the property.

Roof Maintenance

Regular roof maintenance is essential to prevent water ingress and damage. Inspecting and replacing damaged or missing tiles, maintaining the flat canopy over the front door, and ensuring proper drainage can help protect the roof structure. Regular inspections and prompt repairs can extend the lifespan of the roof.

Conclusion

The Cussins house represents a significant chapter in the history of British housing. Built to address the post-war housing crisis, these properties offer unique architectural features and construction methods. However, they also come with potential hazards and risks that buyers and investors must consider.

Conducting thorough inspections, understanding the typical defects, and planning for necessary maintenance and repairs are crucial steps in safeguarding your investment. At Flettons, we’re committed to safeguarding your investment. When considering a property purchase, trust our seasoned expertise to reveal any hidden threats. For a thorough building survey, get your instant quote through our quote calculator or reach out directly at 0203 691 0451. Your home’s safety is our top priority.

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