Why Do Walls Crack in Winter?

If you notice new cracks every winter, you're not imagining things. Cold weather really does cause wall cracks. Here's why and what you can do.

The Science

When your furnace runs, it removes moisture from the air. Dry air makes wood shrink. Your home's framing, which expands in humid summer months, contracts in dry winter months.

Drywall doesn't shrink the same way, so when the wood frame moves, the drywall cracks - usually along seams and at stress points like door and window corners.

Why Some Houses Are Worse

• Newer homes: Lumber hasn't fully dried yet, so there's more movement
• Older homes: May have more dramatic temperature swings
• Houses with big temperature/humidity variations
• Homes with wood-burning heat sources (very dry air)

What You Can Do

Control humidity: A humidifier in winter keeps indoor humidity around 30-40%, reducing the extreme swings that cause movement.

Don't over-heat: Keeping your house cooler (say, 68°F instead of 74°F) means less moisture removed from the air.

Give it time: New homes settle most in the first few years. The cracks usually become less frequent over time.

Fixing Winter Cracks

Wait until spring to repair cracks that appear in winter. As humidity rises, some cracks will partially close on their own. Repairing in winter often means the repair will crack again when conditions change.

For the repair itself:

1. Clean out loose material


2. Apply joint compound


3. Use paper tape over larger cracks


4. Sand and paint

When to Worry

Cracks that only appear in winter and go away in summer are usually just seasonal movement - annoying but harmless.

Cracks that keep growing, are wider than 1/4 inch, or have one side higher than the other could indicate structural issues. Get those checked out.

Seasonal cracks are a normal part of owning a home in a climate with real winters. Control what you can and fix the rest each spring. Learn more in our guide to what causes cracks in walls.