3 steps to get rid of mould before painting

Even if you're not going to paint, you need to get rid of that mould. Here's what to do.

You thought you had a mould problem, but you've really got a moisture problem. Microscopic mould spores are everywhere. It's when they find a wet place to grow that they become a hazard to property and to human health. Mould will degrade and stain almost any material it grows on. The black mould that grows on wet building materials, especially drywall, tends to be the toxic kind. Inhalation can cause allergic reactions and respiratory problems.

Significant mould infestation cleanup, such as after a flood, is dangerous and should be handled professionally. This guide is for attacking small isolated areas of mould, such as in a kitchen or bath. When dealing with mould and mould removal products, it's advisable to wear a face mask, eye protection, and rubber gloves.

Here are the three things to do before painting over mould:

Whether it's a leaky pipe, roof or window, you've got to eliminate the conditions in which mould thrive. In kitchens and bathrooms, consider installing a powerful fan. Calculate the volume of your room and buy a fan appropriate for its size.

There's always going to be humidity in basements due to the porous nature of concrete, but if your basement is especially damp, you may have leaks in your foundation. Luckily, these can often be fixed. Use a dehumidifier during warm months, and heaters in the winter. Humidity in homes should be around 50 per cent.

There is disagreement among many sources concerning the best way to clean up mould. Possible cleansers including borax, vinegar, and hydrogen peroxide. The CDC recommends soap and water or a bleach solution of one cup (237 ml) bleach to one gallon (3.8L) water. To play it safe, you may wish to buy a mould removal product in a home supply store.

To apply the bleach solution on drywall, use a sponge to wipe away mould. Don't saturate the material. The bleach should cause the stain to fade. Let it dry completely before priming.

Drywall that's been soaked through and is growing mould should be cut out and replaced. Wood that's had mould growth should be allowed to dry and then sanded before priming.

Buy a mould inhibiting primer/sealer. Get a product that's specifically formulated to be used on mould. Keep adding layers of primer and sealer, allowing it to dry between coats, until the stain is no longer visible. For the topcoat, consider using a specialty paint that's mould resistant.