Blistering and cracking of stucco wall surfaces are mainly caused by water and moisture seeping through the finish. Water gathers in one spot, weakening the finish and stucco material over time and causing the finish coat to blister.
Although severe stucco repairs should be left to a masonry or stucco repair contractor, most blisters and cracks should be easy to repair if you have do-it-yourself knowledge. The type of damage, such as the extent of the fracture, will affect how these repairs are carried out.
Stucco Recipe:
The basic formula for a stucco finish coat mix will be fairly similar to that of a base coat recipe, with the exception that extra water will be used to thin down the material since it is often applied at a thickness of roughly 1/8".
1. In a big bucket, mix the scratch coat of stucco using an electric drill and paddle-bit attachment.
2. Fill the bucket with 1 part portland cement and 2 1/4 to 4 parts sand.
3. The texture's smoothness is determined by the amount of sand used; the more sand used, the smoother the texture.
4. Slowly drizzle in the water and swirl with the paddle until you have a thick paste that can be distributed on your surface.
5. To help the topcoat adhere, apply with a trowel and then scratch with a mason's scratcher.
Repairing A Stucco
You might be able to repair a damaged section of stucco larger than a small hole, around a square foot or so, yourself. The most difficult part will be matching the texture of the stucco restoration to that of the original. Before you begin, make sure the damage isn't the result of poor installation or moisture that has gotten beneath the stucco. In certain cases, contact a Stucco repair contractor.
1. Break Off Loose Stucco
Before you fix flaws and cracking parts of stucco, remove any damaged stucco and debris, as well as some intact stucco surrounding the repair area, with a hammer or chisel. Remove any damaged stucco until you reach the metal mesh that protects the lath beneath. To remove loose dirt and dust, use a wire brush to clean the area.
2. Remove The House Wrap And The Lath
Cutaway the house wrap or felt paper near the damaged stucco using tin snips and remove the lath. However, leave the lath in place and wrap it around the fine stucco you removed.
3. Cover the Lath That Is Exposed
Cutting two pieces of grade D construction paper to suit the patch area to create an effective moisture barrier, each piece should cover all exposed wood materials. As needed, staple the first sheet of paper to the wood lath or plywood sheathing. Overlap the second piece of paper with a staple.
4. Add Metal Mesh
Examine the metal mesh beneath the removed plaster for any corrosion or damage. You can use it to apply your fresh stucco if the stucco inspection appears to be in good shape. Otherwise, cut the old mesh using metal snips to remove it. Replace the metal mesh. Cut a piece of galvanised metal mesh to size after measuring it. Use galvanised roofing nails inserted into the wood lath below to secure it.
5. Mix The First Coat Of Stucco Repair
Traditional stucco repair mix, which must be prepared in a wheelbarrow or plastic tray according to the manufacturer's instructions, or pre-made stucco repair mix, which is ready to trowel on. Regardless of the sort of quality stucco, you're working with, look for a combination that cures quickly.
6. Apply The First Coat
With a trowel, apply the first layer, often known as a "scratch" coat. Scratch the stucco material's surface with a putty knife or trowel to help the following layer adhere to the last. Allow for drying as directed by the manufacturer.
7. Apply The Scratch Coat Of Stucco Repair Mix
Water the margins of the stucco around the patch area (to prevent premature drying of the new stucco). Scoop a fistful of wet stucco onto a trowel, then fling it over the metal lath to embed the wet mix into the mesh's holes. Rep until the entire repair area is covered, then smooth the stucco into a level, even layer that is within 1/2 inch of the original stucco surface.
To connect the new stucco with the old, carefully push and smooth the wet stucco over the margins of the repair. Scarify the scratch coat using a trowel or scarifier, then cure according to the mix manufacturer's instructions.
8. Apply The Brown Coat
Prepare the stucco mix and coat the area with the coat, often known as a "brown" coat. With a putty knife or trowel, etch the stucco surface. Let dry.
9. Apply The Final Coat
For the final, or colour, coat, mix a batch of stucco. To create the desired effect, this coat might be a standard or custom-order colour. However, colour-matching a patch such that it fits in with the surrounding stucco is challenging; properly concealing a patch sometimes necessitates painting or coating the entire wall with a comparable paint or pigmented coating.
With a trowel, apply the last layer so that it is flush with the surrounding area. If desired, texture the coat to match the original finish. Allow the stucco to cure according to the instructions.
10. Paint
If you couldn't match your new stucco to the old stucco or if your stucco needs a new colour update, paint your complete stucco exterior once you've repaired it.