Understanding the Pemcrete House

The Pemcrete house is a distinctive type of system-built property that emerged in the UK during the post-war period, specifically between the 1950s and 1960s. These homes were part of a broader movement to address the housing shortage by employing innovative construction techniques. Manufactured by Gibson & King, Pemcrete houses are known for their unique construction methods and materials, which set them apart from traditional brick-and-mortar homes.

Historical Context and Manufacturing

Period Built and Typical Locations

Pemcrete houses were predominantly constructed in the 1950s and 1960s, a time when the UK was grappling with a significant housing shortage. The need for rapid and cost-effective housing solutions led to the development of various system-built properties, including the Pemcrete house. These homes can be found in various parts of the UK, often in suburban areas where there was ample space for new housing developments.

Manufacturers and Designers

The primary manufacturer of Pemcrete houses was Gibson & King, a company known for its expertise in prefabricated construction. The designers of these homes aimed to create a durable and affordable housing solution that could be quickly assembled on-site. The use of prefabricated reinforced concrete (PRC) panels was a key feature of the design, allowing for faster construction times compared to traditional building methods.

Characteristics of Pemcrete Houses

Types and Styles

Pemcrete houses come in various forms, including bungalows, two-storey detached, semi-detached, and terraced houses. This variety made them a versatile option for different types of homeowners, from single individuals to large families. The homes typically feature a medium pitch hipped or gable roof covered with concrete tiles, which adds to their distinctive appearance.

External Features

One of the most recognizable features of Pemcrete houses is their rendered external walls. The gable apex often includes vertical timber boarding or PRC panels, adding to the aesthetic appeal. Some bungalows also feature a gable front bay that spans the separating wall, providing additional architectural interest.

Internal Features

Internally, Pemcrete houses were designed with practicality in mind. The ground floor is typically made of concrete, while the first floor consists of timber joists supported by a precast concrete (PC) ring beam and a rolled steel joist (RSJ). Ceilings are usually plasterboard, providing a smooth and clean finish.

Construction Details

Substructure

The substructure of a Pemcrete house includes concrete strip footings and brick under-building, providing a solid foundation. Precast concrete (PC) ground beams and a damp-proof course (DPC) are also integral parts of the substructure, ensuring stability and moisture resistance.

External Walls

The external walls of Pemcrete houses are constructed using eaves height PRC corner columns and T-section PRC columns at junctions with separating walls. The walls are rendered and consist of storey-height tray-shaped PRC panels in various widths. These panels are complemented by a 1-inch cavity and 2 1/4-inch Paramount linings. Reinforced concrete (RC) ring beams are used at the first-floor level and eaves level, providing additional structural support.

Roof

The roof of a Pemcrete house is constructed using timber trusses and is covered with concrete tiles. The gable apex is often clad with vertical tongue-and-groove (T&G) timber boarding, adding to the home’s visual appeal.

Partitions and Separating Walls

Internal partitions are typically made of 2 1/4-inch Paramount panels, while separating walls consist of 10-inch concrete blocks lined with plasterboard on timber battens. In the roof space, 9-inch concrete blocks are used for additional support.

Typical Hazards and Risks

Structural Issues

One of the primary concerns with Pemcrete houses is the potential for structural issues, particularly related to the PRC panels. Over time, these panels can deteriorate, leading to cracking and movement. This can compromise the structural integrity of the home and may require significant repairs.

Moisture and Damp

Due to the use of concrete and PRC panels, Pemcrete houses can be susceptible to moisture ingress and damp issues. Proper maintenance of the damp-proof course (DPC) and regular inspections are essential to prevent these problems.

Insulation and Energy Efficiency

Pemcrete houses were built during a time when energy efficiency was not a primary concern. As a result, these homes may have inadequate insulation, leading to higher energy costs. Retrofitting modern insulation materials can help improve energy efficiency and reduce utility bills.

Defective Premises Act and Pemcrete Houses

Classification as Defective

Under the Defective Premises Act, certain types of system-built properties, including some PRC homes, have been classified as defective. This classification means that the homes may not meet modern building standards and could pose safety risks to occupants. Pemcrete houses, due to their use of PRC panels, may fall under this classification, making it essential for potential buyers to conduct thorough inspections and seek professional advice.

Implications for Buyers

If a Pemcrete house is classified as defective, it can have significant implications for buyers. Mortgage lenders may be hesitant to provide financing for such properties, and insurance premiums could be higher. Additionally, buyers may need to budget for potential repairs and upgrades to bring the home up to modern standards.

Inspection Tips for Pemcrete Houses

Exterior Inspection

When inspecting a Pemcrete house, start with a thorough examination of the exterior. Look for signs of cracking or movement in the render and PRC panels. Pay close attention to the gable apex and any vertical timber boarding, as these areas can be prone to deterioration.

Roof Inspection

Inspect the roof for any missing or damaged concrete tiles. Check the condition of the timber trusses and ensure that there are no signs of rot or decay. The gable apex should also be inspected for any issues with the vertical T&G timber boarding.

Internal Inspection

Inside the home, check the condition of the concrete ground floor and timber joists on the first floor. Look for any signs of moisture ingress or damp, particularly around the DPC and in areas where PRC panels are used. Inspect the plasterboard ceilings for any cracks or signs of movement.

Structural Integrity

Assess the overall structural integrity of the home, paying close attention to the PRC panels and RC ring beams. Any signs of deterioration or movement should be noted, as these could indicate potential structural issues that may require professional intervention.

Common Defects in Pemcrete Houses

Cracking and Movement

Cracking and movement in the render and PRC panels are common defects in Pemcrete houses. These issues can compromise the structural integrity of the home and may require significant repairs.

Moisture Ingress and Damp

Moisture ingress and damp issues are also common in Pemcrete houses, particularly if the DPC is not properly maintained. Regular inspections and maintenance are essential to prevent these problems.

Insulation and Energy Efficiency

As mentioned earlier, Pemcrete houses may have inadequate insulation, leading to higher energy costs. Retrofitting modern insulation materials can help improve energy efficiency and reduce utility bills.

Variants of Pemcrete Houses

Bungalows with Gable Front Bay

Some Pemcrete bungalows feature a gable front bay that spans the separating wall. This design adds architectural interest and provides additional living space.

Storey Height PRC Panels

In some variants, the external walls are constructed using storey-height PRC panels. These panels provide additional structural support and can help improve the overall stability of the home.

Gable Wall Apex of PC Panels

Another variant includes a gable wall apex made of PC panels. This design provides additional structural support and can help improve the overall stability of the home.

Stepped String Course

Some Pemcrete houses feature a stepped string course, adding architectural interest and providing additional structural support.

Foil-Backed Plasterboard Linings

In some variants, the internal linings are made of foil-backed plasterboard on timber framing. This design can help improve insulation and energy efficiency.

Conclusion

Pemcrete houses are a unique and distinctive type of system-built property that emerged in the UK during the post-war period. While they offer a range of benefits, including rapid construction and affordability, they also come with potential risks and hazards, particularly related to the use of PRC panels.

When considering the purchase of a Pemcrete house, it is essential to conduct a thorough inspection and seek professional advice to ensure that the home meets modern building standards and is free from significant defects. By understanding the characteristics, construction details, and potential issues associated with Pemcrete houses, buyers and investors can make informed decisions and safeguard their 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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