What is damp and mould?

Damp
Damp is the presence of unwanted moisture or water in the property. It can occur for various reasons, such as leaking roofs, faulty plumbing, rising damp from the ground, or condensation. Dampness can lead to a range of problems, including the deterioration of building materials, the growth of mould, and potential health issues for the occupants.

There are several forms of damp such as:

  • Rising damp is when moisture is able to travel through the dampproof course of your home (just above ground level) and may result in damp up to 1m high above the ground floor.
  • Penetrating damp is caused when water soaks a wall and travels through into your home. This may be caused by leaks, flooding or defective guttering and seals around your bath, shower, basin and sink.
  • Condensation damp comes from the moisture in the air in your home, it’s increased when cooking, cleaning, bathing, and even breathing. Condensation will form on the coldest surfaces in your home, these cold areas are usually around windows, the corners of the room, and external walls. Condensation mainly occurs during cold weather, regardless of whether it’s raining or dry. It isn’t necessarily a problem, as long as the surface has time to dry out every day. The warmer the air temperature is in your home, the more moisture it can hold. 

The most common form of damp is from condensation and, from time to time, particularly in colder months, affects most homes in the UK. Damp occurs in moist places that may never fully dry out, usually where there is little air movement. Normally, this may be easily controlled by keeping surfaces dry

Mould
Mould is a type of fungus that thrives in damp and humid conditions. It reproduces by producing tiny spores that can become airborne and spread. Mould can grow on various surfaces, including walls, ceilings, carpets, and furniture. It often appears as black, green, or brown patches and can have a musty odour. Exposure to mould can cause respiratory problems and allergic reactions in some people.

The relationship between damp and mould
Damp conditions create an ideal environment for mould growth. When moisture levels are high, and there is insufficient ventilation, mould spores can settle on damp surfaces and start to grow. As mould colonies develop, they can release more spores into the air, contributing to indoor air quality issues and potential health hazards.

Addressing damp problems, fixing leaks, improving ventilation, and maintaining proper humidity levels are essential steps to prevent both dampness and mould growth in buildings. Additionally, prompt identification and remediation of areas with mould are crucial to prevent further damage and protect the health of occupants.