Tips for fighting basement mildew

If you encounter the unpleasant sight and smell of mildew in your basement, here are easy steps you can take get rid of them once and for all.

• For an especially dirty concrete or concrete-block surface, you can make your own solution to get it clean. Just add detergent and 50 millilitres (1/4 cup) of ammonia to a bucket of warm water.
• Brush the solution over the surface with a stiff nylon brush. (Never use a metallic brush; metallic fibres can get trapped in the concrete and rust.)
• For really stubborn dirt, get an extra kick by adding trisodium phosphate to the wash water. TSP is available at hardware stores.
• Rinse with a hose and let dry. Use a shop vacuum to remove excess water.

• Mildew in a basement gives off an unpleasant, musty odour. To freshen up your basement, open windows to let in air, use fans to improve air circulation, and install a dehumidifier to remove moisture.
• To get rid of the fungal growth that's the source of the smell, mix up a brew of 30 to 60 millilitres (1/8 to 1/4 cup) of household bleach per litre (four cups/one quart) of water in a spray bottle. Spray the walls and floors with the solution and scrub them with a nylon-bristled brush.

• An easier solution for the floor in a smelly basement is to sprinkle it with chlorinated lime (bleaching powder; sold in the supermarket's laundry section). Let it sit there for a day, soaking up the bad odour and the microorganisms that cause it, then sweep or vacuum it up. Dispose of the sweepings outdoors.
• If the odour persists, seal the concrete with concrete sealer.