Cornish units are properties built of non-traditional construction and were built using precast reinforced concrete (PRC) construction. These properties were built in large numbers, typically in the 1940’s to1960’s as a result of housing shortages following the second world war.

There are two different types of Cornish unit. A Type 1 Cornish Unit typically includes precast concrete construction at ground floor level and have a timber frame mansard construction with a flat roof and dormers above. A Type 2 Cornish Unit is typically built using precast concrete at both ground and first floor levels.

Both types of Cornish unit are deemed to be defective and are typically unmortgageable due to their non-traditional construction. It is possible to remove and rebuild the relevant elements of these properties in traditional and modern materials however, these works are usually expensive and disruptive, as well as requiring the relevant statutory consents for the works to be undertaken, upon satisfactory completion, the homeowner would also require a specialist PRC certificate to be provided in order for the property to be considered as possible suitable security for lending purposes (subject to individual lender criteria and requirements).

Whilst known as ‘Cornish Units’, this type of construction is not just found in Cornwall and can be found in other parts of the UK.