Foundation problems
Cracks Around Windows and Doors
There are cracks at the corners of my windows and doors. Is that the foundation?
Sometimes. Openings are the weakest points in a wall, so they crack first when a house is bent by foundation movement, and diagonal cracks running away from a corner are the classic signature. But they are also where ordinary drywall cracks appear from seasonal humidity and normal building movement. The distinguishing evidence is direction, whether the crack repeats after repair, and whether the door or window itself has started to bind.
We are a referral service, not a contractor. Your request goes to an independent Calgary foundation company.
This one splits both ways. The specifics below decide it.
What you are probably seeing
- A crack running diagonally up and away from the top corner of a door or window
- The crack wider at one end than the other, tapering along its length
- The door or window sticking, binding, or no longer latching properly
- Cracks that reappear in the same place within months of being filled
- The same pattern at several openings in one part of the house
- Gaps opening at the top of a door frame or between trim and wall
What causes it
- Differential foundation settlement
- When part of a foundation drops relative to the rest, the structure above is bent, and it relieves that at the weakest points: the corners of openings. This is the version that matters.
- Ordinary drywall movement
- Seasonal humidity change, timber shrinkage in a newer house and normal building movement all crack drywall at opening corners without any foundation involvement. Very common and not a problem.
- Framing shrinkage in a new build
- Timber dries and shrinks over the first couple of years. Cracking at openings during that period is expected and usually stops on its own.
- Clay soil moving seasonally
- On clay, a house can move slightly with the seasons, opening cracks in dry months and closing them in wet ones. A crack that visibly opens and closes through the year is describing this rather than progressive failure.
- Roof or structural load changes
- A removed wall, a poorly supported beam or an added load can bend the structure from above, producing the same pattern with no foundation problem at all.
How serious is yours?
The left column is worth acting on. The right column is genuinely fine to watch, and saying so is the point of this page.
Get this assessed
- Get this looked at: The crack is wider than roughly 6mm
- Get this looked at: The door or window has gone from working to unusable
- Get this looked at: The same pattern appears at several openings clustered in one area
- Get this looked at: Floors slope in that part of the house
- Get this looked at: The crack keeps returning after repair
- Get this looked at: There are diagonal cracks in the foundation itself, or in exterior brick or stucco
Reasonable to monitor
- A hairline crack at a single opening in a house under about three years old
- A crack that opens slightly in winter and closes in summer
- A crack filled once that has not come back
- One sticking door in a house with no other symptoms anywhere
How it is usually dealt with
Establish whether it is structural first
Filling the crack before knowing this wastes the most useful evidence you have. Mark it, date it, and see whether it returns or grows.
Cosmetic repair
Where the evidence points to ordinary drywall movement, taping and filling is the appropriate and complete response.
Floor elevation survey
Where several openings are affected in one area, measuring floor levels across the house establishes whether real differential movement exists behind the pattern.
Address the foundation
Where the survey confirms differential settlement, the repair is under the foundation rather than at the crack. Cosmetic work goes last, after the movement is stopped.
The Calgary angle
Calgary's clay soils and the pronounced wet-spring, dry-summer swing produce genuine seasonal movement in some houses, which shows up as cracks at openings that widen through the dry months and close again. That behaviour is informative rather than alarming: a crack that opens and closes on a cycle is behaving differently from one that only ever widens, and telling those apart takes little more than a pencil mark and a year of patience.
What to do next
These cost nothing and make any later assessment considerably more useful.
- Photograph each crack with a scale and mark the ends in pencil with today's date
- Note every affected opening on a rough floor plan, since clustering matters more than count
- Test each affected door and window and note whether it binds
- Check whether floors slope in the same part of the house
- Re-check in three to six months before deciding anything, unless a marker in the serious list applies
The repair page for this problem
If you have decided it needs attention, this is the page covering what the work involves and what it costs.
Foundation settlement repairQuestions people actually ask
Are cracks above doors always a foundation problem?
No, and most are not. Opening corners are where drywall cracks naturally from seasonal humidity and ordinary building movement, particularly in newer homes where framing is still drying. It becomes a foundation question when the pattern repeats at several openings in one area, when the door or window starts binding, when floors slope in that part of the house, or when cracks keep returning after repair.
Why do my doors stick in some seasons and not others?
Two things do that. Humidity swells and shrinks the door and frame directly, which is harmless. Seasonal soil movement under the foundation, common on the clay soils around Calgary, flexes the house slightly through the year and can bind a door as it does. The distinguishing test is whether anything else moves with it: floors, cracks and other openings in the same area.
Should I fill these cracks or leave them?
Leave them until you know what they are, unless they are unsightly enough to bother you. An unfilled crack is a free monitoring device: it tells you whether movement is continuing. If you do fill it, photograph and date it first so you can tell whether the crack that appears later is the same one returning.
How much crack width is a problem?
Roughly 6mm is the commonly used prompt to get an opinion, but width alone is a weaker signal here than pattern and change. A 2mm crack that has reappeared three times at the same door corner, alongside a floor that slopes, says more than a single static 8mm crack in an otherwise unaffected wall.
Not sure what you are looking at?
Send a description and a postal code. It goes to an independent Calgary foundation contractor who can tell you what it is.
We are a referral service, not a contractor. Your request goes to an independent Calgary foundation company.