The science of mould: how it grows, spreads and comes back

Mould is not complicated once you see the mechanics. It is a living fungus that spreads by airborne spores, grows wherever a surface stays damp enough, and gives off gases you smell before you see it. This is the science of mould in plain English: how it grows, why it comes back, and what the research says about controlling it.

Most advice about mould skips the why. These guides do not. Start with how mould works and why it comes back for the overview, then go deeper on whichever part matters to you.

The science, guide by guide

The data

We also compile public data into citable resources: the Renter Mould Index ranks the capitals by damp risk, the mould season calendar shows when mould peaks where you live, and which homes get the most mould breaks it down by dwelling type and age.

The words explained

New to the terminology? The mould glossary defines spores, hyphae, dew point, MVOCs, ergosterol and the rest in plain English.

The thread running through all of it is simple. Mould needs moisture. Deal with the moisture and the air, and you deal with the mould. For the evidence behind our own blend, see the lab results.