Air

How do I prevent and fix mould?

Short answer

Mould points to too much moisture. Ventilate, heat evenly, keep furniture away from cold outer walls and have leaks or thermal bridges repaired. WHO links damp and mould to respiratory symptoms and asthma.

Explanation

WHO states that persistent damp and mould growth in buildings should be avoided or minimised. Owners are responsible for a healthy building; occupants for sensible use of water, heating and ventilation. Moisture often condenses behind large furniture against outer walls.

Rules of thumb

• Place cupboards a few centimetres away from outer walls. [SW-S20]
• Keep humidity between 40 and 60 %. [SW-S20]
• Air bedrooms for 5–10 minutes after getting up. [SW-S20]

Pitfalls

• Just cleaning mould away without tackling the source of moisture lets it come back. [SW-S29]
• For large areas or health complaints: ask an expert or your GP for advice. [SW-S29]

By region

BEBelgium NLNetherlands

Tenants: report damp problems to the landlord in writing; rules differ by region and country. [SW-S29]

Search terms

These search terms are in Dutch; only terms that also find a topic in English are links.

schimmel vocht condens koudebrug astma

Read also

• What humidity is healthy at home?
• How do I air my home without losing much heat?

Sources

1. SW-S20 Wie lüfte ich richtig? Tipps und Tricks zur Schimmelvermeidung — Umweltbundesamt (DE) (Reference date 2026-09-27)
2. SW-S29 WHO Guidelines for Indoor Air Quality: Dampness and Mould — Executive summary — WHO via NCBI Bookshelf (Reference date 2026-09-27)

Reference date: 2026-09-27 · Translated with AI from the Dutch original.