How To Do Stucco Repairs

At first glance, the seamless coat of stucco on the Due east Boston house looked as bulletproof every bit a sidewalk, the perfect foil against the harsh wet atmospheric condition of this coastal city. Withal beneath its lush cloak of ivy, the cement shell was a mess of cracks and buckling, signs that h2o had gotten in and damaged the underlying wood lath.

When properly installed, stucco (a cement- or lime-based plaster) is about as carefree and long-lived a cladding equally anyone could wish—100 years is not uncommon. Simply when big cracks or blisters appear, the time to make repairs is right away, before the damage grows.

Antonio DiSilva of MJM Masonry performed the remedial piece of work on the Eastward Boston house over ten days, ripping off loose material and patching information technology with three split coats. Here'south how to brand stucco repair that lasts.

Stucco Recipes

Stucco Recipes

Get-go coat:

ane⁄2 bag (47 lbs.) Portland cement
6 shovels brick or masonʼs sand, slightly damp
1 shovel hydrated lime
ane⁄two loving cup acrylic bonding amanuensis

Second and terminate coats:

1⁄ii bag (47 lbs.) portland cement
8 shovels amass sand for concrete
1 shovel hydrated lime
ane⁄2 cup acrylic bonding agent

Directions:

Shovel the dry ingredients into a wheelbarrow and alloy them with a mortar hoe.
Add the acrylic bonding agent, and then stir in water, a little at a time, until the mix reaches the consistency of buttercream frosting.
Too much water volition make information technology loose and unworkable.
In one case water is added, the mix will stay usable for 30 to 90 minutes before it starts to harden.

Watch The Weather

Freezing temperatures can ruin wet stucco. Look for nighttime temperatures that stay above forty degrees earlier tackling repairs. Hot, dry, windy weather can also interfere by sucking out moisture the mix needs to cure properly. Work in the shade so the stucco doesn't dry as well fast. Between coats, keep the patch moist past covering it with a plastic sheet.

Piece of work Safely

The alkalis in moisture cement tin cause burns. So when working with fresh stucco, habiliment gloves or touch the mix only with your tools, non your fingers. Keep a bucket of water nearby to launder whatsoever splashes off your skin.

Finish It Right

No patch, no matter how expertly textured, will match the color of the old stucco effectually it. To do that, you need to apply a pigmented coating over the unabridged surface. The patch at this business firm was covered with a thick, sprayed-on acrylic elastomer that bridges and seals hairline cracks. Other acceptable coatings include physical paints and stains, mineral paints, lime washes, and "fog coats" of pigmented cement. Whichever coating y'all use, make certain it's alkaline metal tolerant and permeable to h2o vapor. Otherwise, it will be peeling off in no fourth dimension.

Steps for Repairing Stucco

Stride 1: Suspension Off Loose Stucco

Whack it with a hammer, or a hammer and a cold chisel, taking care not to impairment the underlying wood board supports. Heart protection is a must.

Pace 2: Chip Abroad At The Edges

Continue until you achieve stucco that's firmly adhered to its lath. Cut any metal mesh with snips.

Step 3: Cover The Exposed Board

Using a utility knife, trim a slice of grade-D builder'due south paper to fit tightly along the boundary where the old stucco meets the exposed wood lath. Fasten the newspaper to the lath with roofing nails, then put a second layer of paper on peak of the beginning.

Step 4: Add Mesh

Place galvanized metal lath over the paper and trim information technology tight against the edge of the stucco. Snips with offset handles will brand this task easier. Drive more than roofing nails through the mesh and into the wood lath.

Stride 5: Mix The Stucco

Following the get-go-coat recipe, stir upward a batch of stucco, using a wheelbarrow equally a mixing basin. The acrylic bonding agent added to this mix improves the adhesion of the new stucco to the old.

Step half dozen: Sling It

Moisture the border of the old stucco so information technology won't suck wet out of the patch and weaken the bond between old and new. Scoop fist-size wads of wet stucco onto a brick trowel and toss them against the wire lath until it's completely covered. Smooth the mix with a finishing trowel, then pack it against the border of the existing stucco with a brick trowel. Proceed adding more than textile until this layer is near 1/2 inch below the existing stucco surface.

Footstep 7: Scratch It

When the patch loses its wet sheen, score its surface to ameliorate the bond to the next glaze. Tape a plastic sail over the patch to keep information technology from drying out.

Step 8: Employ Second Coat

Wait 7 days, then remove the plastic and mist the patch with water. Mix upward a batch of stucco following the 2nd-coat recipe, and trowel on a iii/viii-inch-thick glaze, working from the lesser up. Pack downwardly the edges with a brick trowel. Wait for the moisture sheen to disappear, and so trowel the patch smooth, just below the level of the existing stucco. Comprehend again with a plastic canvass.

Step 9: Put On The Finish Glaze

After three days, remove the plastic, mist the patch, and mix up a fresh batch of stucco, following the stop-coat recipe. Different textures require different techniques. To match this wall's original "dash" terminate, DiSilva scooped small globs of wet mix onto his brick trowel, so flicked them confronting the wall until they were flush with the old surface.

Footstep x: Expect To Paint

Let the patch cure for a week before painting it and the residue of the wall. Nether a glaze of heavy-bodied acrylic elastomer, the patch is invisible.

Tools: