The Problem
Tens of thousands of PRC properties still remain, and structural repairs are needed because of the long term decay of concrete.
The post-war non-traditional housing program was a remarkable period in the history of UK housing. Some precast reinforced concrete (PRC) homes structural weaknesses came to light in the 1980s when occupants were first offered the right to buy. A survey of PRC homes, carried out by the Building Research Establishment, established a generic problem of carbonation of the concrete, due to inadequate protection of the steel reinforcement. As a result, more than 20 types of PRC homes were designated as defective and immediately became unmortgageable.
To restore confidence, Government grants were made to ensure that the homes were properly repaired, the Government approached NHBC to set up and administer a repair scheme. This scheme eventually repaired over 13,000 homes, adopting tailored repair procedures for most of the defective house types. The scheme was run by PRC Homes a subsidiary of NHBC, and offered certificates of repair acceptable to mortgage lenders, unfortunately these grants were only offered over a ten year period and are no longer available.
By the mid 1950s the construction of non-traditional houses was beginning to decline, though some types like Wimpey No-fines continued to be built in large numbers. Timber-frame construction, however, did secure long-term popularity among house builders and today, for low-rise, remains the UK’s main alternative to masonry. Though not adopted as a long-term solution for the structural frames of houses, precast concrete did find its niche in medium- and high-rise apartments where it has become the principal framing and cladding material. Steel frame has been a somewhat less common solution for housing since the post-war period, however, it has its advocates, who value the flexibility provided by the light structures that can be designed.
Additionally, mortgage lenders show a reluctance to continue to lend on many of these properties, or to offer home insurance, leaving owners and tenants wishing to buy with few options.