Warning Signs
Sticking Doors: Humidity or Foundation?
The short answer
Sticking doors can be harmless seasonal humidity swelling the wood, or a sign the foundation is shifting and racking the door frame out of square. Tell them apart by the pattern: humidity affects exterior/wood doors in summer and resolves; foundation movement makes a door suddenly drag, the frame look out of square, or several doors stick at once.
A door that sticks isn’t always a foundation problem
In Central Texas humidity, wood doors swell and stick every summer — that’s normal. But a sticking door is also one of the most common early signs of foundation movement, because as the foundation shifts, it racks the wall and pulls the door frame out of square. Telling the two apart saves you worry (or catches a problem early).
How to tell the difference
Probably just humidity if:
- It’s an exterior or solid-wood door
- It sticks in summer and frees up when it’s dry
- The gap around the door is still even
- It’s the only symptom
Possibly foundation movement if:
- It started suddenly or won’t latch at all
- The gap around the door is uneven (wider at the top or bottom)
- The frame or door looks visibly out of square
- Interior hollow-core doors are sticking too
- It’s happening alongside cracks, sloping floors, or gaps
The quick test
Open the door halfway and let go. If it swings or drifts on its own, the frame is probably out of plumb — a sign the foundation has moved. Then look at the gap (the “reveal”) around the closed door: a foundation problem usually makes that gap noticeably uneven, tapering from one side to the other.
When to act
One mildly sticking exterior door in August? Watch it. Several doors sticking, a door that won’t latch, or sticking plus other warning signs? Get a measured inspection. And if you’re curious how much your soil moves in the first place, check your address — homes on expansive clay rack their door frames far more often.
Frequently asked questions
Do sticking doors always mean foundation problems?
No. In humid Texas weather, wood doors swell and stick, then free up when it dries — that's normal and harmless. The concern is doors that stick suddenly, won't latch, show a frame that's visibly out of square, or stick alongside other signs like cracks and sloping floors.
How do I tell humidity from foundation movement?
Humidity swelling is seasonal, gradual, and usually affects the door slab edges (especially exterior/solid-wood doors), easing in dry weather. Foundation movement racks the whole frame — the gap around the door becomes uneven (wider at top or bottom), the door won't latch, and the problem persists regardless of weather.
Which doors are the best indicator?
Interior hollow-core doors and the corners of door frames are good tells, because they're not very sensitive to humidity. If those start sticking or the frame goes out of square, it points more toward structural movement than weather.