The Craftcast House

The Craftcast house, also known as the Jones & Harvey house, is a non-traditional reinforced concrete property type developed in the 1940s. Designed by Craftcast Ltd and manufactured by Jones & Harvey, approximately 200 units were constructed during the post-war housing shortage. Surviving examples are relatively rare and are most commonly found in suburban settings.

A Craftcast House illustrating flat reinforced concrete roof construction and rendered concrete external walls with characteristic detailing.

Craftcast houses were constructed using reinforced concrete throughout much of the structure. They were built as bungalows and as two-storey detached or semi-detached houses. The design incorporates flat reinforced concrete roofs with overhanging eaves and cast-in box gutters.

External walls are generally formed from 7-inch reinforced concrete with vertical and horizontal reinforcement, incorporating 1.5-inch woodwool slabs for insulation. Some variants include 6.5 or 7-inch dense or lightweight (Cheecol) reinforced concrete, or 8-inch no-fines reinforced concrete. The outer surface is typically rendered or coated in cement paint, often with thickened quoins forming mock column details. Formwork impressions are frequently visible.

Separating walls are usually 8 inches thick reinforced concrete. Internal partitions are commonly 4-inch concrete, although 4.5-inch reinforced concrete internal walls and fibreboard linings are also seen in certain variants.

Ground floors typically comprise tongue-and-groove wooden blocks set in bitumen on a concrete base. First floors consist of tongue-and-groove wooden blocks laid on a 6-inch reinforced concrete slab bearing onto the external walls and partitions, with woodwool insulation. Staircases are formed in reinforced concrete.

Roofs are formed from 5–6 inch reinforced concrete cambered slabs with overhanging eaves and reinforced concrete dentils beneath the overhang. Asphalt coverings provide the primary waterproofing layer.

The principal structural risk in Craftcast houses relates to corrosion of embedded steel reinforcement within reinforced concrete elements. Where moisture penetrates, corrosion can lead to cracking and spalling, reducing durability and potentially affecting structural performance.

The flat reinforced concrete roof with asphalt covering and cast-in box gutters presents an ongoing maintenance requirement. Failure of the waterproof covering or blockage within box gutters can allow persistent moisture ingress.

Original woodwool insulation may not achieve modern thermal performance standards. This can affect comfort levels and heating efficiency.

Given the period of construction, asbestos-containing materials may be present within finishes or service components. Identification and appropriate management are essential where asbestos is encountered.

A Craftcast house will appeal to purchasers who understand reinforced concrete system-built construction and are prepared for ongoing inspection and maintenance of flat roof and concrete elements.

• Commission a comprehensive building survey prior to purchase
• Assess the condition of reinforced concrete and roof coverings carefully
• Review maintenance history, particularly roof and gutter repairs

Where reinforced concrete deterioration or long-term moisture issues are evident, further specialist advice may be required.

Craftcast houses are not specifically designated as defective under the Defective Premises Act. However, as a reinforced concrete non-traditional construction type, lending decisions may depend on condition, evidence of structural performance, and clarity of professional reporting.

Well-documented maintenance, absence of significant concrete deterioration, and clear survey findings are often influential in mortgage and resale discussions.

A building survey provides an informed assessment of the visible condition and construction of a Craftcast house. Inspections are non-intrusive and limited to areas that are accessible at the time of inspection.

• Identify visible cracking and spalling to reinforced concrete walls and roof slabs
• Assess signs of dampness, moisture ingress, and flat roof defects
• Comment on box gutter detailing and external envelope condition
• Review the general condition of accessible floors, ceilings, and structural elements
• Highlight defects that may require repair, monitoring, or further investigation

However, there are limitations to what a survey can determine without intrusive investigation.

• Confirm the condition of concealed steel reinforcement within reinforced concrete
• Assess hidden structural elements behind finishes or linings
• Determine the full extent of internal corrosion or concrete deterioration
• Inspect areas that are inaccessible or covered at the time of inspection

Where higher-risk indicators are identified, further specialist or intrusive investigation may be recommended.

For a thorough building survey in Greater London, an instant quotation can be obtained through the online survey calculator.