Fix a ceiling that has a crack

Steps

Goal: Confirm the crack pattern and size, rule out water damage and structural issues, then patch or call a pro.

• Inspect the ceiling. Note whether the crack is hairline, vertical, stair-step, or horizontal—and whether it is in drywall or plaster.
• Good: Crack visible—proceed to Check for water damage.
• Bad: Ceiling looks intact—you may have a different problem (stain, sag).

Check for water damage

Goal: Rule out a leak above before patching.

• Look for water stains, discoloration, or dampness near the crack. If the ceiling is dry, proceed to Check if crack suggests structural issues.
• If you see wet or stained areas, there may be a roof or plumbing leak above. Fix the leak before patching—otherwise the crack will return. Call a roofer or plumber if needed.
• Good: Area is dry—proceed to structural check.
• Bad: Water damage present—fix the leak first.

Check if crack suggests structural issues

Goal: Rule out foundation or structural damage before patching.

• Stair-step cracks in brick or block often indicate foundation movement. Horizontal cracks can mean soil pressure. Cracks wider than 1/4 inch or growing need a pro.
• If doors or windows nearby stick or bind, that can signal settling. Call a foundation or structural professional to assess.
• Good: Crack is hairline or narrow vertical—proceed to Hairline path or Wider path.
• Bad: Stair-step, horizontal, or wider than 1/4 inch—call a pro.

Hairline crack — spackle and paint

Goal: Patch a narrow crack with spackle so it is invisible and stable.

• Scrape out loose material with a utility knife or small screwdriver. Wipe with a dry cloth. The crack should be clean and dry.
• Apply spackle with a putty knife, pressing it into the crack. Overfill slightly. Let dry per the product label (usually 1–2 hours).
• Sand with 120-grit sandpaper until smooth and flush. Wipe away dust. Apply primer, then paint to match the ceiling.
• Good: The crack is filled and the surface is smooth—done.
• Bad: Crack reappears—may need pro or structural assessment.

Wider crack — joint compound and tape

Goal: Patch a wider crack with mesh tape and joint compound so it does not reappear.

• Apply self-adhesive mesh tape over the crack. Spread joint compound over the tape with a putty knife, feathering the edges.
• Let dry per the product label. Apply a second thin coat if needed. Sand smooth when dry.
• Apply primer, then paint to match the ceiling.
• Good: The crack is covered and the surface is flat—done.
• Bad: Crack reappears—call a pro to assess.

When to get help

Call a foundation or structural professional if:

• The crack is stair-step (in brick or block).
• The crack is horizontal.
• The crack is wider than 1/4 inch or growing.
• Doors or windows nearby stick or bind.

Call a roofer or plumber if there is water staining or dampness—fix the leak before patching.

Confirm you have assessed the crack type before calling. For related fixes, see Fix a wall that has a crack or Fix a floor that squeaks.

Verification

• The crack is filled or covered and the surface is smooth and painted.
• The repair blends with the surrounding ceiling.
• The crack does not reappear after the patch dries (if it does, call a pro).
• No water stains or dampness near the crack (if there was, the leak was fixed first).