My Stucco Looks Bad, and I Need to Repair Stucco Cracks and Paint

There’s nothing more annoying than seeing cracks on your exterior stucco. You might ask, “Do I need to repair stucco cracks and paint?”

Types of stucco cracks

The good news is that cracks on stucco are relatively easy to correct. And you definitely should, even if they’re just hairline cracks. Otherwise, you’ll be in for more extensive (and expensive) repairs. You don’t want to wait until these hairline cracks get more comprehensive and more complicated to deal with, so it’s better to fix them while early (apart from the fact that you can’t simply stand the sight of them).

The following lists the different types of cracks on stucco surfaces (and their possible causes):

  • Hairline cracks – This type is a typical stucco crack, less than 1/8 of an inch. Various factors, such as improper mud mixture, foundation settlement, or a minor seismic movement, can cause them.
  • Spider cracks – When you see spider cracks on your stucco walls, they’re usually a result of poor application of the mud in the stucco mixture.
  • Pattern cracks – Cracks forming a particular pattern are usually found in wood-framed homes. When you see those cracks, they might indicate that the lath (a framework, usually a metal mesh, for the mud stucco to adhere) had a problem during installation.
  • Diagonal cracks – Diagonal cracks mainly indicate severe foundation damage resulting from structural settlement or shifting. They are usually bigger than 1/8 of an inch and found around door or window frames or AC units.

How to repair stucco cracks

Repairing stucco cracks vary slightly depending on their size and severity.

For hairline cracks:

  • Wet the wall down. The water will eliminate any standing dirt in and around the crack and allow you to apply the caulking more easily.
  • Apply the caulking to the crack.
  • Compress and smooth the caulk by pressing your moistened finger over it.
  • Wipe off excess caulking.
  • Let the caulking dry (if you plan to paint over it afterward).
  • Apply latex paint over the caulked surface, preferably the same color as the surrounding stucco finish.

For more significant cracks (reminder: wear goggles and heavy gloves to protect yourself from cuts):

  • Widen the crack (yes, you read that right) to at least a quarter inch using a cold chisel and hammer. The edges of the crack should be chiseled crosswise to the surface.
  • Cut away any rusted or torn metal lath and any torn building paper beneath the lath. Next, brush the area clean to remove any loose debris.
  • Cut a new piece of building paper to match the size of the area you are repairing. Secure it firmly to the sheathing or studs using a staple gun. Make sure the building paper overlaps the wrap on the margins that you have left intact. Seal around the wrap seam with exterior caulking.
  • Cut a new piece of metal lath to the size of the area you are repairing. Secure the new lath to the wall by stapling it or using lath or roofing nails.
  • Pour enough amount of stucco repair compound into a bucket. Have a drill and mixing paddle attachment, and mix the stucco compound thoroughly within 20 minutes. If you mix longer than that, the stucco compound will dry out and end up unusable. Another option is to use a pre-mix stucco compound.
  • Load your caulk gun with the stucco compound.
  • Using the caulk gun, apply the stucco compound along the crack. While applying the compound, trowel the stucco compound to match the existing stucco surrounding it.
  • Allow the patched area to cure for 24 hours.
  • After curing the patched area, apply latex paint, preferably the same color as the current stucco finish surrounding it.

You may notice that despite the cured stucco repair compound, the finished job feels somewhat flexible when you touch it. Don’t worry, though, as the stucco repair compound’s elasticity attests to its strength. Should the walls move slightly due to seismic activity or any other reason, the patch will adjust instead of breaking down.

With the stucco cracks patched and painted over, you can rest assured that moisture from rain and snow won’t be able to get behind the stucco.

Stucco is known for its durability, but it doesn’t mean it will never have surface issues. With wear and tear over time, it can develop cracks and even holes. When I need to repair stucco cracks and paint, follow the instructions above on how to do it or hire a licensed and insured professional painter for stucco repairs and painting.