Water damage and mould
Drying out within 48 hours after a flood, sewer backup or burst pipe, and when to call a restoration firm.
How to stop water damage turning into mould
Mould needs damp. Health Canada says to dry the house and its contents within 48 hours of a flood to make mould less likely; materials that stay wet longer, such as drywall, insulation and carpet, usually have to come out (Health Canada).
Make it safe, then record it
Stay out until the power to the wet area is off. Before you move anything, photograph the water line, the walls and every damaged item for your insurer.
Get the water out and dry within 48 hours
Remove standing water with pails or a pump, finish with a wet/dry vacuum, then open up when the weather allows and run fans, or close up and run a dehumidifier (Health Canada).
Take out what can’t be dried
Soaked flooring, insulation, drywall, carpet, particleboard furniture and mattresses go. Cut soaked drywall and insulation to at least 50 cm (20 in) above the water line, and clean hard surfaces with unscented detergent.
Safety: Treat sewer water as sewage: children, pregnant people and anyone with breathing problems should not handle it, and everyone else needs gloves, boots, goggles and a mask. Never run a gas-powered pump, heater or dryer indoors to dry out (Health Canada).
What helps
A dehumidifier with a pump and an air mover do the drying; an N95 mask for the clean-up.
Dehumidifiers
Frigidaire 50 Pint Built-In Pump Dehumidifier with Wi-Fi
Built-in pump sends water up to 16.4 ft, so no bucket to carry
Lasko 12″ Air Mover Blower Fan, 3-Speed, 2 Outlets
Pivoting 289 CFM blower for drying wet floors and walls
Smoke masks
Moldex 2200N95 N95 Particulate Respirator
NIOSH N95 (TC-84A-0327) with a foam nose seal and no metal strip
Find a restoration firm
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Our guide
Questions about water damage and mould
How fast must a basement dry after a flood?
Health Canada says to dry the area within about 48 hours, with fans or dehumidifiers, to limit mould. Run the dehumidifier with windows and doors shut, and empty or drain it continuously.
What has to come out after a flood?
Health Canada says to discard soaked flooring, and drywall, insulation, carpet, mattresses and particleboard furniture that flood water reached and that can’t be dried. Anything soaked by sewage may have to go too. Photograph everything for your insurer first.
Is it safe to run gas equipment while drying?
Not indoors. Health Canada warns that gas-powered pumps, heaters and dryers used inside to dry a basement cause carbon monoxide build-up. Use electric equipment on a safe circuit and keep a working CO alarm.
Do I need bleach to clean up mould?
No. Health Canada says bleach isn’t needed for mould: clean hard surfaces with unscented detergent, and watch for green or black spots, stains or a musty smell.
When should I call a professional for mould?
Health Canada suggests professional help for extensive mould, meaning a patch larger than 3 m². Mould from a sewer backup is a job for professionals too.
Will my insurance cover water damage?
It depends on your policy, especially for sewer backup, so call your insurer before large work starts. Photograph the water level, the walls and every damaged item before you move anything, and keep the receipts for the clean-up; our flooded basement guide goes through it. If you think a sewer backup came from a fault in the city’s sewer, ask your municipality to check it.
Comes with
Flooding
Keeping water out of the basement, a pump running when it rises, and what to do first if it gets in.
Frozen pipes
Keeping water pipes above freezing in a cold snap or an outage, and what to do when one freezes.