Understanding the Anvil House

The Anvil House, a distinctive property type in the UK, was manufactured by Anvil Enterprises Ltd between 1965 and 1979. Known for its unique design and construction, the Anvil House is also referred to as the Anvil 6B or Kilpeck. With approximately 850 units built, these properties are primarily found in suburban areas, offering a mix of bungalows and two-storey detached, semi-detached, and terraced houses.

Design and Construction Characteristics

Anvil Houses are easily identifiable by their medium pitch gable or monopitch roofs, typically covered with tiles. The external walls are constructed using a platform frame method, featuring storey-height timber frame panels based on a 2-foot module. These panels are sheathed externally with plywood, overlaid with bituminous building paper, and separately clad with brick. The walls are lined with plasterboard backed with a polyethylene vapour control layer, with mineral fibre insulation between the frame studs.

The roof structure consists of timber trusses, bituminous felt, timber battens, and tiles, with mineral fibre insulation laminated to a polyethylene film at ceiling level. The ground floor is made of concrete, while the first floor comprises plywood on timber joists. Ceilings are finished with plasterboard, providing a clean and smooth appearance.

Variants and External Features

Anvil Houses exhibit several external wall variants, including:

• Vertical cedar boarding throughout
• Horizontal cedar boarding below windows
• Stone or tile hanging on timber battens
• Painted or rendered finishes to the ground floor window head level

These variations offer a range of aesthetic options, allowing homeowners to choose a style that suits their preferences.

Typical Hazards and Risks

While Anvil Houses boast a robust construction, they are not without their challenges. One common issue is the differential movement of first-floor window sills, which can lead to gaps in the vapour control layer. This can result in moisture ingress and potential damage to the internal structure. Additionally, the system was also used for flats, which may present unique challenges in terms of maintenance and repair.

Defective Premises Act Considerations

Anvil Houses are not classed as defective under the Defective Premises Act. However, it is essential for potential buyers and investors to conduct thorough inspections to identify any existing or potential issues. Engaging a professional surveyor can help ensure that any concerns are addressed before purchasing.

Inspection Tips for Anvil Houses

When inspecting an Anvil House, consider the following steps to ensure a comprehensive evaluation:

1. Exterior Examination: Begin by assessing the external walls for any signs of damage or wear. Look for cracks, gaps, or signs of moisture ingress, particularly around window sills and door frames.

2. Roof Inspection: Check the roof for missing or damaged tiles, as well as any signs of water damage or leaks. Ensure that the timber trusses and battens are in good condition and free from rot or decay.

3. Internal Assessment: Inside the property, examine the plasterboard walls and ceilings for any signs of cracking or movement. Pay particular attention to areas around windows and doors, where differential movement may be more pronounced.

4. Vapour Control Layer: Inspect the vapour control layer for any gaps or breaches, which could allow moisture to penetrate the structure. This is particularly important in areas where differential movement has been observed.

5. Insulation Check: Ensure that the mineral fibre insulation is intact and properly installed between the frame studs and at ceiling level. This will help maintain energy efficiency and prevent heat loss.

6. Flooring Evaluation: Examine the concrete ground floor and plywood first floor for any signs of damage or wear. Look for uneven surfaces, cracks, or signs of moisture ingress.

7. Structural Integrity: Assess the overall structural integrity of the property, paying close attention to the timber frame and any signs of rot or decay. This is crucial for ensuring the long-term stability and safety of the building.

Common Defects in Anvil Houses

While Anvil Houses are generally well-constructed, they are susceptible to certain defects. Some of the most common issues include:

• Differential Movement: As previously mentioned, differential movement of first-floor window sills can lead to gaps in the vapour control layer, resulting in moisture ingress and potential damage.

• Moisture Ingress: Due to gaps in the vapour control layer or damaged external cladding, moisture ingress can occur, leading to rot, decay, and structural damage.

• Insulation Issues: Inadequate or improperly installed insulation can result in heat loss and reduced energy efficiency, leading to higher energy bills and a less comfortable living environment.

• Roofing Problems: Missing or damaged tiles, as well as issues with the timber trusses and battens, can lead to water damage and leaks, compromising the integrity of the roof structure.

• Structural Concerns: Over time, the timber frame may be susceptible to rot or decay, particularly if moisture ingress is present. This can affect the overall stability and safety of the property.

Maintenance and Repair Tips

To maintain the integrity and value of an Anvil House, regular maintenance and timely repairs are essential. Consider the following tips to keep your property in top condition:

1. Regular Inspections: Conduct regular inspections of the property, both inside and out, to identify any potential issues early on. This will allow for timely repairs and prevent further damage.

2. Address Moisture Issues: If moisture ingress is detected, address the issue promptly to prevent rot, decay, and structural damage. This may involve repairing gaps in the vapour control layer, replacing damaged cladding, or addressing roofing issues.

3. Insulation Upgrades: Ensure that the insulation is properly installed and in good condition. Consider upgrading to more energy-efficient materials if necessary to improve energy efficiency and reduce heating costs.

4. Roof Maintenance: Regularly inspect the roof for missing or damaged tiles, and address any issues promptly to prevent water damage and leaks. Ensure that the timber trusses and battens are in good condition and free from rot or decay.

5. Structural Repairs: If any structural concerns are identified, such as rot or decay in the timber frame, address these issues promptly to ensure the long-term stability and safety of the property.

Investment Potential of Anvil Houses

Despite the potential challenges, Anvil Houses offer a unique investment opportunity for home buyers and investors. Their distinctive design and construction, combined with their suburban locations, make them an attractive option for those seeking a property with character and charm.

When considering an Anvil House as an investment, it is essential to conduct thorough due diligence and engage a professional surveyor to assess the property’s condition. This will help identify any existing or potential issues and ensure that the investment is sound.

Conclusion

Anvil Houses, with their unique design and construction, offer a distinctive option for home buyers and investors in the UK. While they present certain challenges, such as differential movement and moisture ingress, these issues can be addressed with regular maintenance and timely repairs. By conducting thorough inspections and engaging a professional surveyor, potential buyers can ensure that their investment is sound and that the property remains in top condition.

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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