General Information

MISSION STUCCO COLORED EXTERIOR is factory prepared by a member of the Stucco Manufacturers Association. All ingredients conform to standards established by the Association.


• Application should be over a base of uniform thickness and suction.

• Mix in a mechanical mixer for 10 minutes.

• To avoid joinings mix enough at one time to complete one unbroken elevation to a natural break in the wall.

• For continuous mixing, when the elevation is complete, add a new batch to the remaining material in the mixer and carefully control the amount of water added, for the next elevation.

• For hand application dampen the brown coat with water to create a uniform suction.

• One person should do all the floating or texturing to keep the finish consistent.

• In hot dry windy weather, water curing may be needed. When necessary a fog spray of water should be done within 24 to 48 hours.

• Do not retemper after the set has begun.

FLOAT FINISH - Uniformly moisten the brown coat and allow the water to dissipate. Trowel the first coat on 1/10' thick. Trowel a final finish coat over the firm first coat to a natural break. Joinings of fresh and set coats shall not occur except at natural breaks (corner, angle, screed, etc.). Float uniformly using an absolute minimum of water and taking care not to lap joinings.

DASH FINISH - The first dash application over the brown coat shall cover the dry surface and create a uniform color and suction on the wall. The second dash coat shall be applied after the first is dry and shall assure uniformity of color and texture. If over monolithic concrete apply a thin "parge" coat and hand tool for maximum compaction. Allow it to set at least 24 hours and then proceed with the dash finish described above.

TEXTURED FINISHES - For surface treatments other than float and dash, consult "Stucco Textures & Finishes" and/or your plastering contractor. When a heavy texture is specified the manufacturer should be informed to insure proper formulation for the thicker finish.

SANDBLAST & RESTUCCO - Some preparation must be done before sandblasting. The dirt should be trenched to allow blasting below ground level. The plants may have to be trimmed to allow access to the walls. Sandblasting must remove the old paints and some of the stucco finish to a sound surface. If there are any questionable areas, use Tie Bond. After the building has been restuccoed, a water repellent may be advisable before filling in the trench with enough dirt to keep water from standing against the stucco.


• During the winter months the base of the wall may get a green Mildew on lt. Usually this comes from an older wooden roof. Using a bleach mixed with 112 water will remove it immediately. After the treatment, rinse the wall with water.

• When washing down an exterior wall to remove dust, etc., start wetting the wall at the ground level and work your way up the wall. If you start at the top and work down, the dirty water from the top will be absorbed by the dry wall area below. From the bottom up the dirty water is going over a wet wall.

• A new wooden roof can emit a water soluble stain that can turn any stucco wall brown or black where it-runs down the wall. Diverting the runoff will keep this from happening.

• At the corners of window and door frames you will find the weakest part of the wall. There may be cracks on an angle from these corners. These are structural cracks that if repaired will appear again after the next earthquake. The cracks are unsightly but should not cause a leak because there is a water repellent paper behind the stucco that is the moisture barrier.

ALKALI & EFFLORESCENCE - New construction is now required to have a weep screed at the base of the wall. This keeps the stucco above the dirt line. Unfortunately older construction has the stucco below the dirt and at times this can cause some problems. Alkali appears on the stucco surface as a white film or as a growth of white crystals. It is important to realize that alkali is not from faulty stucco or improper application, but rather a deposit of mineral salts from a variety of possible sources. For alkali to appear, there must be 3 conditions. There must be water soluble salts present, there must be sufficient water to dissolve the salts and there must be a path for the salts to move through the wall to the surface. If anyone of these 3 conditions is missing, alkali will not be a problem. When the ground is damp and the sun is making the wall hot, it is natural for the ground water to travel up into the wall and evaporate out of the wall into the air. If this water carries the salts you will have an alkali problem. Two possible solutions are, cutting through the stucco to the concrete foundation to form an air gap, or covering the stucco from the foundation below the stucco to the ground line with a non setting, non hardening mastic. Alkali can be removed with acid. Acid and alkali will neutralize each other. A safe acid is a 5% white vinegar which will usually do the job. Spraying vinegar on the base of the wall every Spring and Fall may be enough to control some alkali problems. In the dirt near the stucco, the use of an acid fertilizer will help control alkali salts. In all cases there should be a build up at the base of the building to keep the water draining away. It is not advisable to pour concrete up against the stucco. If the stucco starts above and the poured cement is against the foundation there will be less problems.

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Mission Stucco Co 7751 E. 70th Street, Paramount, CA 90723

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Phone: (562) 634-1400 Fax: (562) 634-4440   Email

Phone: (562) 634-1400 Fax: (562) 634-4440   Email