How you repair stucco depends on how much damage has been done. A large hole in the wall will need to be scraped away and reapplied. Since you’re unlikely to find stucco that matches the rest of the surface exactly, it’s best to paint over the entire surface to make it look clean. GoldLeaf Designs, custom home builders in Philadelphia, says, “A stucco patch will stick out like a sore thumb. If you want the surface to look uniform again, you’ll have to paint over it.” However, if you just have some cracks in your stucco, you can fill them in with caulk. You’ll still be left with an unsightly patch that is best painted over, but fixing a crack is much simpler than repairing large holes. It’s best to catch cracks quickly before they become large holes.
Even larger cracks can be filled with a premixed stucco patch. You won’t need to mix your own stucco unless there are large holes. If you need to patch a large hole, follow the steps below. You will need work gloves, safety glasses, a hammer, a chisel, nails, and a trowel.
Step 1: Completely Remove the Loose Stucco
Remove any loose stucco with a hammer and chisel until you get to solid stucco around the edges. Stop once you reach the metal mesh underneath. When you get to the metal mesh, carefully cut it out and remove any fasteners. Brush the area clean to remove any debris.
Step 2: Apply Building Paper & Metal Lath
Next, apply grade D building paper to act as a moisture barrier. This will protect the wood underneath from damage. Use staples to apply one piece and then add a second layer on top. Next, add your new metal lath. Make sure you cut it to be the exact size of the patch. There should be no gaps between the lath and edges of the hole. Nail the lath into the wall with appropriate nails for the material your wall is made of.
Step 3: Mix Your Stucco
Only mix enough stucco to use within 20 minutes. If you take any longer, it will dry out and become unusable. Use a bucket or wheelbarrow to hold the mixture. You should be able to use a drill and mixing paddle to properly mix your stucco. Check one more time for any debris and wet the patch with a spray bottle before you begin. Moisture helps the mixture adhere to the wall properly. Once the surface is prepared, you can begin adding your first layer.
Step 4: Apply 3 Coats of Stucco
The first layer is called the scratch coat. Cover the metal lath entirely with a layer of stucco. Put on your gloves and use your trowel to apply the stucco. Once that layer dries, scratch the surface with X patterns. These patterns are why it’s called the scratch coat. It might seem counterintuitive to damage the layer you just applied, but it actually helps the next coat adhere better. Allow that layer to cure by covering it with plastic and holding the plastic there with painters tape. Once it’s firm enough, add the second layer and cover it back up. The only layer that should completely dry is the final layer.
Once the second layer is cured, spray it with your water bottle again. Then apply your final layer. You don’t need to cover the final layer, but you do need to smooth it out to be flush with the rest of the wall. The patch will likely stand out. Unfortunately, the only way to make the wall the same color now is to paint the whole surface. This will add an extra layer of protection to the wall.
Step 5: Paint the Entire Surface
Before you can paint, you’ll need to wait seven to 10 days for the stucco to fully cure. How long you should wait depends on the product you buy. Once enough time has passed, you can apply your painter’s tape and a coat of exterior masonry primer. Brush the edges and roll on the rest. The primer will need time to dry as well. Check the label on your product to find out how long to wait. As with the primer, brush your exterior masonry paint around the edges and roll on the rest. Let the first coat of paint dry and apply a second coat. Carefully remove the painter’s tape, and you’ll have a uniform surface in color and texture. Are you planning on painting over your old stucco? Let us know in the comments!
This article is provided by Jennifer Bell who is a freelance writer, blogger, dog-enthusiast and avid beachgoer operating out of Southern New Jersey.