Is mould lurking in your home?
By Michelle Warren • Bankrate.com

"I've done new houses where the reason for the mould was because of the building products installed," says Lindsay.

Sometimes the faulty materials come from suppliers; other times, wood and the like are not stored properly during construction or the partially finished building is not sealed at the end of a work day and is subjected to the elements. If damp materials, such as drywall, are used during building, you have the foundation for ongoing problems.

"It could happen to any house," says Wilkinson. "The concern areas are places where water can be trapped and contained for any length of time."

Do you have mould?
Sometimes mould shows up around windows, on walls, under carpets, on ceiling tiles and along the foundation of a house, but it can also hide inside walls. Discolouration and a musty odour are key signs that there is too much moisture in a home.

Mould often occurs after a flood or as the result of a leaky roof, poorly sealed windows, a cracked foundation or burst pipe. Materials, such as insulation or drywall, are sponges for moisture and breeding grounds for mould. However, as Wilkinson points out, "Mould doesn't show up overnight, therefore it's important to tackle moisture right away."

Disasters aside, when mould is present, "it usually comes down to building science," says Lindsay, who points to poor ventilation as the main culprit. Damp, cool areas are a breeding ground for fungi.

DIY or call a professional?
As a rule of thumb, small areas of mould can be killed with a fungicide; however, anything beyond a square metre should be tackled by a professional.

Bleach is one of the most common weapons for cleaning moderate amounts of mould, but experts don't recommend it. Not only are the fumes harmful to humans, bleach is tough on the environment. Lindsay also warns that bleach can simply mask mould by turning it white; a better approach is to buy a mould control fungicide, such as Concrobium Mould Control ($10 to $180 depending on the size of the container) from a hardware store. During removal, wear rubber gloves, as well as a respirator mask.

Some people opt to paint over mould, but this only masks it -- paint doesn't kill mould. It will continue to grow and reappear until the source of the moisture is fixed and a fungicide is applied. "You've got to find out what's causing the moisture," says Lindsay. "Complete removal is the only way to fix it."