The aggregate used for the Mundic concrete was a slate rock material which was taken from the numerous heaps of soil left by mining, especially tin mining, in the area. Mundic concrete can perform satisfactorily for many years until it gets damp, then a complex reaction causes the concrete to expand and disintegrate. Once this process starts, deterioration is progressive and often rapid and can seriously affect the
structural stability of the property. Therefore in all instances where Mundic Concrete is identified a Mundic report must be commissioned and referred to the valuer before any lending decisions can be made.