If the floor above it is cold, the crawl space is usually the reason - and the fix is almost never more carpet.
The vented crawl space problem
A lot of older Calgary houses have crawl spaces with vents to the outside, built on the old theory that ventilating the space would keep it dry.
In this climate that theory does not hold up well. In winter you are deliberately admitting outside air into a space directly under your floor, which makes the floor cold and pulls heat out of the house continuously. In summer, warm humid air entering a cool crawl space can condense on the cold surfaces down there - so venting can actively add moisture rather than remove it.
The modern approach is generally the opposite: seal the crawl space, bring it inside the building's thermal envelope, and control moisture from the ground rather than trying to dilute it with outside air.
That is a real change to how the space works, not just an insulation upgrade, and it should be done deliberately.
Ground moisture comes first
The soil under a crawl space gives off moisture continuously. Before insulating anything, that has to be dealt with - normally a continuous ground barrier across the floor, sealed at the edges and seams.
Insulating a crawl space while leaving bare soil open underneath is how you get a sealed, humid box under your house. Any quote that skips this step is not a complete job, and it is worth asking about explicitly.
Where the foam goes
Once the ground is controlled, insulation belongs on the perimeter walls, not stapled up between the floor joists.
Insulating between the joists leaves the crawl space itself cold, which means any plumbing down there is now in an unheated space, and the rim joist above is still leaking. Insulating the perimeter brings the whole space inside the envelope, keeps pipes protected, and lets you seal the rim joist at the same time.
Calgary's freeze-thaw cycling makes the pipe question more than theoretical. A crawl space left outside the thermal envelope, with chinooks swinging conditions around zero repeatedly through winter, is not a place you want water lines.
What this actually fixes
- Cold floors above the crawl space. See cold floors.
- Draughts at floor level on the main storey, because you have closed the low-level air path.
- Pipe freeze risk, once the space is inside the envelope.
- Damp and musty smells migrating upward, once ground moisture is controlled.
Before anyone sprays
Look for standing water, active seepage or any sign of pooling. As with a basement, foam is not waterproofing and must not be used to cover a drainage problem. Fix the water first.
What we do
We are a referral service. We do not install. We connect you with vetted installers - certification, insurance and WCB standing checked - and they quote directly.
No price without a site visit, and a crawl space genuinely has to be looked at: access drives the cost as much as area does. Get a quote.
See also crawl space spray foam insulation province-wide.