Understanding the Concrete Frames House

Concrete Frames houses, designed and manufactured by Concrete Frames Ltd, represent a unique chapter in the history of British housing. Built in 1945, these properties are rare, with only two known to exist. This article delves into the intricate details of these houses, providing valuable insights for potential buyers and investors.

Historical Context and Location

Concrete Frames houses emerged in the post-World War II era, a time marked by a significant housing shortage in the UK. The government and private sector sought innovative construction methods to quickly and efficiently address the demand for new homes. Concrete Frames Ltd, a pioneering company in the construction industry, developed these houses as part of this broader effort.

These properties are typically found in suburban areas, reflecting the post-war trend of expanding residential zones beyond city centres. The exact locations of the two known Concrete Frames houses are not publicly documented, but they likely reside in areas that experienced rapid development during the mid-20th century.

The Visionaries Behind the Design

Concrete Frames Ltd was both the designer and manufacturer of these houses. The company was known for its expertise in precast reinforced concrete (PRC) construction, a method that promised durability and speed. The design of these houses reflects the architectural and engineering innovations of the time, aimed at creating robust and long-lasting homes.

Key Characteristics of Concrete Frames Houses

Structural Features

Concrete Frames houses are two-storey semi-detached properties, a common design choice in the mid-20th century. They feature a medium pitch hipped roof covered with profiled asbestos cement tiles, a material widely used during that period for its fire-resistant properties.

The external walls are constructed from PRC panels, providing a sturdy and weather-resistant exterior. Inside, the houses boast a combination of PRC and clinker aggregate PC blocks, ensuring structural integrity and insulation.

Typical Hazards and Risks

While Concrete Frames houses were innovative for their time, they come with certain risks and hazards that potential buyers should be aware of:

• Asbestos: The use of asbestos cement tiles poses a significant health risk if disturbed. Asbestos fibres can cause serious respiratory diseases, including lung cancer and mesothelioma.
• Corrosion of Steel Reinforcement: Over time, the steel reinforcement within the concrete can corrode, leading to structural weaknesses. This is particularly concerning in properties that have not been well-maintained.
• Carbonation: The process of carbonation can reduce the alkalinity of concrete, leading to the corrosion of embedded steel. This can compromise the structural integrity of the house.

Defective Premises Act

Concrete Frames houses are not classified as defective under the Defective Premises Act. However, their unique construction and potential hazards necessitate thorough inspections and maintenance to ensure safety and longevity.

Inspecting a Concrete Frames House

When inspecting a Concrete Frames house, it is crucial to follow a systematic approach to identify any potential issues. Here are some key areas to focus on:

Roof

• Material: Check the condition of the asbestos cement tiles. Look for signs of wear, damage, or disturbance.
• Structure: Inspect the PRC purlins, ridge beam, common rafters, and ceiling joists for any signs of deterioration or damage.

Walls

• External Walls: Examine the PRC panels for cracks, spalling, or other signs of damage. Pay particular attention to areas around windows and doors.
• Internal Walls: Check the clinker aggregate PC blocks and PRC channel section panels for any structural issues.

Floors

• Ground Floor: Inspect the concrete floor for cracks, unevenness, or signs of moisture ingress.
• First Floor: Examine the PRC T-beams and wood-fibre boarding for any signs of damage or wear.

Main Frame

• Columns and Posts: Check the RC columns and posts at corners, window, and door openings for any signs of corrosion or structural weakness.

Typical Construction Details

Substructure

The substructure of Concrete Frames houses consists of a reinforced concrete (RC) raft underbuilding, thickened under external and loadbearing walls. A slate damp-proof course (DPC) is used to prevent moisture ingress.

Frame

The main frame comprises storey-height RC columns and RC posts at corners, and window and door openings. This robust framework provides the structural backbone of the house.

External Walls

The external walls are constructed from 10 1/2″ x 4″ flanged channel section PRC panels, with a cavity and 2″ clinker aggregate PC blocks. PRC lintels are used over openings, ensuring structural stability.

Partitions

Internal partitions are made from 3″ clinker aggregate PC blocks. The separating wall between semi-detached units consists of PRC channel section panels, a cavity, and clinker aggregate PC blocks lined with plasterboard.

Ground Floor

The ground floor is constructed from concrete, providing a solid and durable base.

First Floor

The first floor features PRC T-beams, supporting the wood-fibre boarding on timber battens. Galvanised hoop iron fixings are used to secure the first-floor ceilings.

Roof

The roof structure includes PRC purlins, a PRC ridge beam, PRC common rafters, and PRC ceiling joists. The roof is covered with profiled asbestos cement tiles, providing weather resistance and fire protection.

Common Defects in Concrete Frames Houses

Despite their robust construction, Concrete Frames houses can suffer from several common defects:

Corrosion of Steel Reinforcement

As mentioned earlier, the steel reinforcement within the concrete can corrode over time, leading to structural weaknesses. This is particularly common in areas exposed to moisture or where the concrete cover is insufficient.

Carbonation

Carbonation can reduce the alkalinity of concrete, leading to the corrosion of embedded steel. This process is accelerated in properties that have not been well-maintained or are exposed to harsh environmental conditions.

Asbestos-Related Issues

The use of asbestos cement tiles poses a significant health risk if disturbed. It is crucial to handle any asbestos-containing materials with care and seek professional advice for removal or encapsulation.

Cracking and Spalling

Cracks and spalling in the concrete can indicate underlying structural issues. These defects can be caused by a variety of factors, including thermal expansion, moisture ingress, and corrosion of steel reinforcement.

Moisture Ingress

Moisture ingress can lead to a range of problems, including mould growth, deterioration of materials, and corrosion of steel reinforcement. It is essential to address any signs of moisture ingress promptly to prevent further damage.

Maintenance and Repair of Concrete Frames Houses

Maintaining and repairing a Concrete Frames house requires a thorough understanding of its unique construction and potential issues. Here are some key steps to ensure the longevity and safety of these properties:

Regular Inspections

Conduct regular inspections to identify any signs of damage or deterioration. Pay particular attention to areas prone to moisture ingress, corrosion, and cracking.

Addressing Corrosion

If corrosion of steel reinforcement is detected, it is crucial to address it promptly. This may involve removing the affected concrete, treating the steel with anti-corrosion coatings, and applying a suitable repair mortar.

Managing Asbestos

Asbestos-containing materials should be handled with care. If removal is necessary, seek professional advice and ensure that all work is carried out in accordance with health and safety regulations.

Repairing Cracks and Spalling

Cracks and spalling should be repaired promptly to prevent further damage. This may involve cleaning the affected area, applying a suitable repair mortar, and ensuring that the underlying cause of the defect is addressed.

Preventing Moisture Ingress

Take steps to prevent moisture ingress, such as repairing damaged roofing, ensuring proper drainage, and applying waterproof coatings to vulnerable areas.

Conclusion

Concrete Frames houses represent a unique and innovative chapter in the history of British housing. While they offer robust construction and historical significance, potential buyers and investors must be aware of the associated risks and maintenance requirements. By conducting thorough inspections and addressing any issues promptly, these properties can continue to provide safe and comfortable homes for years to come.

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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