IN SHORT
- Carpet, underlay and backing are porous and can feed mould when damp.
- Concrete isn't food for mould, but it can hold moisture for a long time.
- Moisture moves into slabs through rising damp, capillary action and vapour.
- If the floor stays damp, growth underneath is very likely.
Carpet and underlay
Carpet, underlay and upholstery are porous materials. When they're made from organic materials, they can support mould growth if they stay wet for long enough. Even carpet that feels dry on top can have damp backing or underlay, and the dust and debris that collect in it add more food.
Concrete
Many people assume concrete floors are safe from mould. Concrete itself isn't a good food source, but the materials sitting on it often are, including carpet backing, underlay, timber and floor adhesives.
Moisture travels through wet concrete and leaves it slowly. Once a slab is damp it can stay that way for a long time, giving mould the moisture it needs in whatever sits on top.
How moisture gets in
- Rising damp: common in older buildings without effective damp-proofing.
- Capillary action: concrete and masonry draw water through tiny pores.
- Vapour movement: water vapour moves through materials from damp areas towards drier ones.
What to do
If your carpet or the slab under it is staying damp, mould growth is very likely, so it is worth finding out why. The moisture needs to be dealt with as soon as practical. Until it is, mould can return. Carpet and underlay with visible growth are often removed rather than cleaned.
WHERE DRYSAFE FITS
Our assessment includes moisture readings, which show where materials are holding moisture. Mould needs moisture, so we take readings and understand where the moisture could potentially be to help you take the right steps to prevent it from reoccurring.