How To Fix Cracks in Stucco

There are three main methods for repairing cracks. We will start with the simplest, most economical method and work our way up to the more comprehensive repair.

1. Surface / Superficial Repair

This is the simplest form of repair. The main function of this repair is to provide a barrier for water that attempts to penetrate at the crack. Typical steps include:
(1) Injection / application of a sealant
A sealant such as NP1 polyurethane sealant or your basic acrylic caulk is commonly used at the cracked site.
(2) Application of additional stucco texture
You can make your own mix (this is what we do) or purchase the stucco finish similar to the one present on the walls (we do this for synthetic finishes).
(3) Paint, if the stucco is painted.
​A heavy coat of paint provides an additional " bridge" over the crack. The elastomeric type of paints in particular provide added flexibility that allows for movement at the crack site while maintaining elasticity and avoiding breaks.

Full Panel Repairs

Irrespective of the type of repair chosen, one critical choice to be made by both the homeowner and prospective contractor is to decide whether repairs need to be made locally (spot repairs) or if there is a need to re-plaster a full panel, a section or even a full side of the house. This is due to differences in texture that may be visible as a patch even after a house is painted in full. Plastering over a full 100-200 SF panel is obviously a more expensive endeavor especially if the crack in question is a thin line over the wall. Have this conversation with your contractor before starting work to ensure this eventuality is considered. Call Today 832-720-6828.

2. Crack Chasing / Routing

A process of crack chasing is a great option for crack repairs that are larger than a hairline (1/16-1/8"). Any crack we deem to be substantially open we will recommend this type of repair. The typical steps include:

(1) Crack chasing / routing 
This is the step where the crack is "opened up". There are various methods to achieve this. Our usual method will entail using power tools to increase the width of the crack. While this may seem counterintuitive, this process allows the application of a larger volume of repair product. Repair products or customized mixes made in the field by technicians will be made to have higher PSI ratings. This means opening up the crack allows the technician to backfill the area of repair with stronger stucco. Additionally, opening up the crack and filling it with enough stucco product actually creates two smaller joints to replace the one crack.

​At the end of the day, the stucco wants to move and that's part of the reason a relief crack was created. The final repair will have two parallel cracks that provide greater freedom of motion for the panels with less movement required at the crack. This movement can be compensated for with applied coatings or paints that will literally bridge the gap on the visible surface while allowing movement underneath.

3. Full Core Replacement of Stucco

Most customers will opt to repair cracks via option 1 or 2. These are usually the most practical and most economical options.
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The source of the cracking problem could be an improper application that goes right down to the initial installation of the metal lath (nail or staple patterns included) or a poor concrete mix design. If these problems are the suspected source of the problem, it is also possible to do a full core demolition and re-installation of stucco either locally at the cracked site, or as a full panel of the area of interest. 

However, sometimes cracking could be due to water damage, as the internal stresses cause a shift in the load on the stucco that causes cracking. These cracks will tend to be concentrated in one area rather than being isolated. Also there will sometimes be "branching" present whereby one crack leads into another crack in a different direction.

When many cracks have developed it is usually advisable to test for water intrusion. A full core replacement may be necessary.