Advanced Techniques for Stucco Repair: Matching the Method to the Damage

Start with the Cause

Every method below starts the same way. Parex, a large stucco maker, says that before damaged finish is repaired, "a root cause analysis is needed," because if the cause isn't corrected, the problem "may reoccur." In practice that means finding where water is getting in, why a crack keeps moving, or what hit the wall, before choosing the repair.

The Methods, from Lightest to Most Thorough

Sealing and coating

For hairline cracks, Parex's repair bulletin calls for two coats of elastomeric coating, about 16 mils wet film each, carried to a corner or edge so the repair doesn't show. A few cracks can be sealed one at a time instead. See how to fix hairline cracks.

Routing and filling wider cracks

For static cracks from 1/16 to 1/4 inch, Parex's procedure routs the crack out to 1/4 inch wide, fills it with a patching compound in two layers, and then coats the area. Widening the crack first gives the filler enough depth to hold.

Patching

Holes and damaged spots are cut back to solid stucco with clean edges, then rebuilt in coats and matched in texture and color. See repairing stucco walls for the steps.

Mesh resurfacing

Where cracks spread across an area, Parex embeds 4 to 6 inch strips of reinforcing mesh in a base coat over individual cracks, or resurfaces the whole area when the cracks are widespread, then applies a new finish. The Stucco Manufacturers Association describes the same idea, a fiberglass mesh embedded in a polymer-modified base coat, as "proven to greatly reduce cracking."

Refinishing blistered areas

Blistered or bubbling finish, Parex notes, "is often caused by water that has gotten behind the finish." After the cause is fixed, its procedure scrapes off the blistered finish, repairs any weak or loose stucco underneath, and applies new finish matched in texture and color.

Remediation behind the stucco

When water has reached the layers behind the stucco on a frame wall, the repair goes deeper: the stucco over the damage comes off, wet or rotted sheathing is replaced, the water-resistive barrier and lath are rebuilt, the flashing is corrected, and new stucco goes on. On wood sheathing, the Florida Building Code calls for two layers of water-resistive barrier behind the stucco. See stucco water damage.

Re-stucco

When damage covers most of a wall, or the old stucco is failing across it, replacing the stucco on that wall can be cleaner than patching it piece by piece. The old stucco comes off, what's behind it is repaired as needed, and new stucco goes on to the code. See stucco replacement.

Repairing EIFS (Synthetic Stucco)

EIFS isn't cement plaster, and it isn't repaired like it. The EIFS Industry Members Association describes it as an insulation board with a base coat reinforced by glass fiber mesh and a textured finish. Repairs use the system's own materials: new insulation board where it's damaged, base coat and mesh lapped onto the sound areas, and matching finish. Knowing whether a wall is stucco or EIFS before any work starts saves time. See stucco siding for the difference.

Why Matching Matters

Whatever the method, a repair that doesn't match shows. The best repairs:

• stop at a corner, control joint or trim line, where an edge looks intentional,
• match the texture, from smooth to sand to hand-troweled,
• finish or paint the whole section of wall, so color differences disappear.

Getting the Right Repair

Choosing the method takes seeing the wall: the cracks, the finish, and what's behind it. Your local Stucco HQ contractor looks at the damage in person and puts the repair and the price in writing, free, before any work starts. See how a stucco repair works, or how to choose a stucco contractor.

Frequently asked questions