Historical Context and Manufacturing Background

The Gee Walker & Slater house, a unique and rare property type, was manufactured in 1946. Only two of these properties were ever built, making them a rare find in the UK housing market. Gee Walker & Slater, the manufacturers, were known for their innovative approach to construction during the post-war period. These houses were designed to address the urgent need for housing in the aftermath of World War II, leveraging materials and techniques that were readily available at the time.

Identifying Characteristics

Gee Walker & Slater houses are two-storey semi-detached properties. They feature a shallow pitch gable roof covered with profiled asbestos cement sheets. The external walls are constructed from aerated concrete panels, pebble-dashed to the first-floor level and roughcast above. The gable apex is panelled, and a smooth rendered band is present at the first floor and eaves level. A distinctive feature is the profiled asbestos canopy over the front door, supported by square posts.

Construction Details

Substructure

The substructure of Gee Walker & Slater houses consists of concrete strip footings and a concrete slab. A damp-proof course (DPC) is also included to prevent moisture ingress from the ground.

Frame

The main frame is constructed from eight rolled steel joist (RSJ) stanchions and one RSJ single-storey stanchion. The frame also includes eight RSJ perimeter beams, two RSJ floor support beams, two RSJ trimmers, and five rolled steel angle (RSA) trussed purlins. The entire frame is coated with bituminous paint for protection against corrosion.

External Walls

The external walls are made from storey-height concrete posts clad with aerated concrete slabs. These slabs are rendered externally with pebble-dash up to the first-floor level and roughcast above. Internally, the walls are lined with aerated concrete slabs.

Separating Wall

The separating wall between the semi-detached units is a cavity wall constructed from concrete posts and aerated concrete panels.

Partitions

Internal partitions are made from concrete posts lined with cement and granulated cork reinforced slabs.

Floors

The ground floor is a solid concrete slab, while the first floor consists of tongue-and-groove (T&G) boarding on timber joists.

Ceilings

Ceilings are constructed from cement and granulated cork slabs.

Roof

The roof is covered with profiled asbestos cement sheets, a common material used in post-war construction due to its durability and fire-resistant properties.

Typical Hazards and Risks

Asbestos

One of the most significant hazards associated with Gee Walker & Slater houses is the presence of asbestos in the roofing material and the canopy over the front door. Asbestos is a known health hazard, and its presence requires careful management and, in some cases, professional removal.

Structural Integrity

The use of aerated concrete panels and steel framing can pose risks related to structural integrity. Over time, these materials can deteriorate, leading to potential issues such as cracking, corrosion, and weakening of the structural frame.

Moisture Ingress

Despite the inclusion of a damp-proof course, moisture ingress can still be a concern, particularly if the DPC has been compromised or if there are issues with the external rendering.

Thermal Efficiency

Gee Walker & Slater houses were built during a time when thermal efficiency was not a primary concern. As a result, these properties may suffer from poor insulation, leading to higher energy costs and potential issues with damp and mould.

Defective Premises Act

Gee Walker & Slater houses are not specifically listed as defective under the Defective Premises Act. However, given their age and the materials used in their construction, they may still present issues that could be considered defects under the Act. It is essential to conduct a thorough survey to identify any potential problems and address them accordingly.

Inspection Guide for Surveyors

External Inspection

1. Roof: Inspect the asbestos cement sheets for signs of damage, wear, or potential asbestos exposure. Look for any missing or broken sheets and check the condition of the canopy over the front door.
2. Walls: Examine the pebble-dash and roughcast rendering for cracks, bulging, or other signs of deterioration. Check the condition of the aerated concrete panels and the smooth rendered band at the first floor and eaves level.
3. Damp-Proof Course: Ensure the DPC is intact and functioning correctly. Look for signs of rising damp or moisture ingress at the base of the walls.

Internal Inspection

1. Frame: Inspect the RSJ stanchions, perimeter beams, floor support beams, trimmers, and trussed purlins for signs of corrosion or structural weakness. Pay particular attention to areas where the bituminous paint may have worn away.
2. Walls: Check the internal aerated concrete slabs for cracks, damp patches, or other signs of deterioration. Inspect the cavity wall separating the semi-detached units for any issues.
3. Partitions: Examine the cement and granulated cork reinforced slabs for signs of damage or wear.
4. Floors: Inspect the concrete ground floor for cracks or unevenness. Check the first-floor T&G boarding and timber joists for signs of rot, warping, or other issues.
5. Ceilings: Look for any signs of damage or deterioration in the cement and granulated cork slabs.

Additional Considerations

1. Asbestos Management: If asbestos is present, ensure it is managed according to current regulations. This may involve professional removal or encapsulation.
2. Thermal Efficiency: Consider upgrading insulation to improve thermal efficiency and reduce energy costs. This may involve adding insulation to walls, floors, and the roof.
3. Moisture Control: Address any issues with moisture ingress promptly to prevent further damage and potential health hazards. This may involve repairing or replacing the DPC, improving ventilation, or addressing issues with external rendering.

Typical Defects and Maintenance

Common Defects

1. Asbestos Degradation: Over time, asbestos cement sheets can degrade, leading to potential asbestos exposure. Regular inspections and maintenance are essential to manage this risk.
2. Corrosion of Steel Frame: The steel frame can corrode, particularly if the protective bituminous paint has worn away. Regular inspections and maintenance are necessary to address any signs of corrosion.
3. Cracking in Concrete Panels: Aerated concrete panels can develop cracks over time, leading to potential structural issues and moisture ingress. Regular inspections and repairs are essential to maintain the integrity of the property.
4. Poor Insulation: Gee Walker & Slater houses may suffer from poor insulation, leading to higher energy costs and potential issues with damp and mould. Upgrading insulation can help address these issues.

Maintenance Tips

1. Regular Inspections: Conduct regular inspections of the roof, walls, frame, and other key components to identify and address any issues promptly.
2. Asbestos Management: If asbestos is present, ensure it is managed according to current regulations. This may involve professional removal or encapsulation.
3. Corrosion Prevention: Maintain the protective coating on the steel frame to prevent corrosion. This may involve reapplying bituminous paint or other protective coatings as needed.
4. Crack Repairs: Address any cracks in the concrete panels promptly to prevent further damage and potential moisture ingress. This may involve filling cracks with appropriate materials and repairing or replacing damaged panels.
5. Insulation Upgrades: Consider upgrading insulation to improve thermal efficiency and reduce energy costs. This may involve adding insulation to walls, floors, and the roof.

Conclusion

Gee Walker & Slater houses are a unique and rare property type with a rich history and distinctive construction features. While they present certain challenges and risks, they can also offer a unique and characterful home for those willing to invest in their maintenance and improvement. By understanding the typical characteristics, hazards, and maintenance requirements of these properties, home buyers and investors can make informed decisions and ensure the long-term safety and integrity of 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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