Mundic: Will Your Building Stand Up To The Test?

Mundic is the term commonly used to describe the failure of concrete blocks resulting from the decomposition of aggregate mineral constituents within the blockwork. This causes deterioration to the block’s structure and consequently the structural integrity of a building. If confirmed, this will result in a property being deemed unmortgageable with a material impact on its value. It should be noted that Mundic is not the same as ‘concrete cancer’ or other forms of concrete degradation.


The production of affected blocks, typically using waste from mining industries, took place from the turn of the 20th century through to the 1950s. Standards were then introduced as mass production of concrete blocks became common, although the use of local inferior materials did continue into the early 1960s and up to 1965 in some very limited circumstances.


In terms of areas in jeopardy, guidance states the whole of Cornwall to be at risk, and those parts of Devon where mining is known to have taken place may also potentially be at risk, including as far east as Tiverton and north as Ilfracombe.


Whether a property is affected by Mundic can only be confirmed by invasive core sample testing undertaken by specialists. Results are placed into classifications, where Class A1, A2 and A3 define mortgageable properties and Classes B and C define properties that are unmortgageable.


On a positive note however, the RICS suggests analysis of 12,000 tests showed that over 80% of properties were found to have Class A samples.


Securing professional valuation and building surveying advice on a building prior to purchasing it can avoid financial losses at a later stage. Stratton Creber Commercial are happy to advise.


Tom Neville BA (Hons) MRICS

RICS Registered Valuer