Tips for a healthy crawl space
A crawl space that is too damp can affect the health of a home’s occupants and wood structure. Read on to find out how to keep your crawl space safe and well insulated.
What is a crawl space for?
Many old houses were built on a crawl space. With limited insulation materials available at the time, this was the most logical way to create a space between the ground and the first floor of the house. A natural soil crawl space is mainly used to prevent soil moisture from infiltrating walls and creating condensation. It also ensures the stability of the building in the event of an earthquake. A crawl space must be properly ventilated for it to function.
How to keep your crawl space healthy
There are various ways to ensure a healthy crawl space: natural ventilation, mechanical ventilation and dehumidification. The first method involves creating drafts that circulate through air vents (grilled screen walls, an air shaft or a PVC or stainless steel tube with grill). For mechanical ventilation, use a fan (or CMV system) equipped with ventilation ducts. This is a good way to introduce clean air and expel stale air. An automatic ventilation system that operates for 20 minutes every hour is ideal.
When these measures are not enough to efficiently renew the air, your best bet is to set up a dehumidifier in the crawl space. It may also be useful to install a layer of regular or expanded polyurethane foam or glass wool for added insulation. Installing a vapour barrier on the ground helps prevent condensation from forming under the floor. You should also check the quality of the wall insulation.
What problems can an overly damp crawl space cause?
A very damp and mouldy crawl space promotes the circulation of mould spores in the house’s air. These can cause allergies and respiratory problems for occupants. A structure damaged by condensation can create areas of rotted wood, which can lead to subsidence in doors, windows, floors and exterior sidings. Other negative impacts include an increased number of insects, bad odours and a higher energy bill.
If you notice signs of contamination (fungi, mould, efflorescence, etc.) in your crawl space, you will need to contact a decontamination professional promptly so that this situation does not affect your health, that of the other occupants or your building’s integrity.