A vented crawl space in Lethbridge is not a passively ventilated space. It is a wind tunnel underneath your floor.
What the wind does down there
Ordinary crawl space ventilation assumes gentle air exchange - some outside air drifts through, moisture drifts out. That model assumes still or near-still conditions.
Lethbridge does not supply those. When wind hits the house it pressurises the windward side and depressurises the leeward side, and a crawl space with vents on opposite walls is a direct path between the two. Air does not drift through it. It is driven through it.
Three consequences follow, and they are all worse than in a sheltered location:
The floor above gets genuinely cold, not just cool, because moving air strips heat from the underside of the floor far faster than still air at the same temperature.
Pipes are at real risk. A water line in a moving-air crawl space at minus twenty loses heat much faster than the same pipe in still air. Wind chill is not just a human comfort number - it describes accelerated heat loss from any warm object, including a pipe.
Insulation between the joists gets undermined. Batt held up between floor joists in a windy crawl space has air moving across and around it constantly. It filters that air rather than stopping it.
Coulee-edge properties
If your house sits near a coulee edge, the exposure is greater again - wind moves up and across the valley with nothing to slow it, and there is often less shelter on that side of a property. Worth mentioning when you enquire, because it moves sealing further up the priority list.
The fix is to stop treating it as outdoor space
- Ground barrier first - continuous across the soil, sealed at seams and edges.
- Close the vents. In this climate they are doing more harm than good.
- Insulate and seal the perimeter walls, bringing the space inside the building envelope. The pipes come inside with it.
- Seal the rim joist at the same time, while there is access.
Done properly the crawl space stays near house temperature, the floor above stops being cold, and the wind no longer has a path under your home.
Water first, always
Foam is not waterproofing. Standing water or seepage gets resolved before anything is applied.
What we do
We are a referral service. We do not install. We connect you with vetted installers - certification, insurance and WCB standing checked.
No price without a site visit. Get a quote, and mention whether there is plumbing in the space and how exposed the property is.
See also crawl space insulation province-wide and frozen pipes in a crawl space.