Is it condensation? If the dampness in a property does not appear to be due to any of the above defects, i.e. rising damp, penetrating damp or leaks, then the likely cause is atmospheric condensation. Condensation occurs mainly during cold weather, whether it is raining or dry, and it does not leave a ‘tidemark’. Mould appears on cold surfaces and in places where there is little movement of air for example in corners, on or near windows, in or behind wardrobes and cupboards particularly on north-facing walls. Life style and our climate are major factors in recent years contributing to condensation problems. Our company offers an advisory service on the causes of condensation and the necessary remedial measures required to avoid the problem in the future. A small fee is charged for this service.