Mundic is a Cornish word meaning mine waste. It consists of iron containing sulphur, known as pyrite and often referred to as fools gold.

Before 1952 concrete was made locally on site from local materials. This was cheaper and more convenient than transporting it long distances. Cornish mine waste was often used as an aggregate in Cornish concrete and here lies the problem.

The Mundic Block Problem

The Cornish mine waste held high levels of minerals and this lead to the deterioration of the concrete over a period of time. Eventually when the problem was identified an ore extraction process was used to remove the minerals but for many houses already built it was too late and the damage from the deteriorating concrete was visible.
Homeowners looking to sell a Mundic Block house will require a concrete screening test to ascertain the extent of any damage, this can have a serious effect on the survey the saleability, and suitability for mortgage lending.  Mortgage lenders may refuse to lend or offer a reduced loan amount meaning any buyer has to pull out.

The Mundic Block Screening Test

The test requires several stages and the quality of the concrete is graded accordingly.
Preliminary Testing. 50mm holes are drilled at random sample points and the concrete is tested in a laboratory for the presence of minerals, the aggregate composition and any deterioration. The results are graded A – C.

  • Grade A samples are free from harmful minerals and is potentially suitable for mortgage lending.
  • Grade AB samples contain small levels of harmful minerals but at a level considered safe.
  •  Grade B samples contain high levels of harmful minerals but with no current signs of deterioration, although prolonged periods of damp or exposure to moisture can accelerate deterioration. Homes classed as Grade B are seen as unsuited for mortgage lending.
  •  Grade C samples show signs of Mundic decay and often need extensive repairs and are only suited to cash buyers.

365 Property Buyer will make a cash offer on any property affected by Mundic Block. Enter your postcode or give our friendly team a call on Freephone 0800 019 7031. If you want to sell a property built out of Mundic Block or affected by Mundic Block deterioration then call now we can help you. 365 Property Buyer have already purchased Mundic Block houses, Mundic Block bungalows and Mundic Block flats.