Buying a House With a Crawlspace: What to Check Before You Close
A general home inspection covers the whole house in a few hours. If the property has a crawlspace in Winnipeg, these are the specifics worth confirming separately.
Why a separate look is often worth it
A home inspector has to assess an entire house in a limited window, and crawlspace access is frequently poor. The scope is necessarily broad.
If you are buying a Winnipeg-area property with a crawlspace — particularly a pre-1980 home, anything with additions, or a rural property on well and septic — a focused assessment tells you what you are taking on. It is cheaper before closing than after.
The four questions that matter most
1. How deep is the support founded?
This is the big one in our climate. Winnipeg’s design frost depth runs roughly 1.8 to 2.4 metres. Support founded above that will move every year, permanently, until it is corrected.
Look for sonotube piers under additions, sunrooms and enclosed porches. Ask whether founding depth can be established. If the addition’s floor slopes or its doors bind seasonally, assume the piers are shallow until proven otherwise.
Correcting this is one of the more expensive crawlspace repairs, so it matters to know before you negotiate.
2. Does the space take water?
Timing is diagnostic, and the viewing season affects what you can see. In August a crawlspace that floods every April can look pristine.
Look for evidence rather than current conditions:
- Efflorescence — white mineral deposits on walls — and note how high it goes, which indicates water level
- Staining or tide lines on walls, posts or the soil floor
- Rust on mechanical hardware, duct work, straps and fasteners
- Silt or sediment patterns on the floor
- A sump pit — its presence tells you someone had a reason to install one; check whether the pump works and where the discharge goes
Ask the seller directly whether the space has taken water, and get the answer in writing.
3. What is the framing moisture content?
This is the number that separates a cosmetic concern from a structural one. Readings above roughly 19 percent mean conditions that support decay.
Have readings taken at multiple points: joists, sill plates, beams, subfloor sheathing, and specifically at the north and east sides and under bathrooms and entries, where we most often find problems.
4. Is the space inside or outside the heated envelope?
Check where the insulation is. Batts between the floor joists with vented walls means the crawlspace sits near outdoor temperature — cold floors above, frost on the subfloor in winter, and plumbing at risk.
Perimeter wall insulation with sealed vents means somebody did it properly.
This determines whether you are buying a finished system or a project.
Also worth confirming
Radon. Manitoba has some of the highest indoor readings in Canada, and an open crawlspace floor is the main entry route. Ask whether a long-term test has been done and request the result. If not, plan to test after you move in — and if the crawlspace is going to be sealed at some point, test first so a collection pipe can be designed in rather than retrofitted.
Structural signatures. Diagonal cracking in stem walls, piers no longer bearing fully, posts sitting on patio slabs or bare soil, beams visibly deflected, sill plates with uneven bearing.
Pest evidence. Droppings, nesting material, chewed insulation or wiring. Chewed wiring should be assessed by an electrician.
Plumbing in the space. Lines running through an unheated crawlspace in this climate are a freeze risk. Look for past repairs, which indicate it has happened before.
Access itself. A 50-centimetre crawlspace reached through a closet hatch costs more to work in for the rest of the building’s life. If a larger permanent access could be cut, that is worth knowing.
What good documentation looks like
Whoever assesses the space should give you:
- Moisture content readings at identified locations, not a general impression
- Photographs of conditions throughout the space
- An assessment of founding depth where it can be determined
- A diagnosis of where water arrives, if there is evidence of water
- A realistic repair cost range, itemized by priority
That is useful negotiating information. “The crawlspace needs work” is not; “the four sunroom piers are founded at approximately 600 millimetres and will need to be underpinned or replaced, at this range” is.
Our position on this
We will inspect a property you are considering, with the seller’s permission and access arranged, and give you the written findings — including when our honest read is that the space is in good condition and needs nothing.
We would rather you buy the house with accurate information than discover the sunroom piers in your second January.