You can apply a new layer of stucco over existing stucco, allowing you to refresh a wall without the hassle of removing the old stucco. Stucco is a masonry mixture of sand, cement and water. When applying stucco over existing stucco walls, you shouldn't need to apply more than two coats.

Application

Prior to applying the new stucco layer, clean the wall thoroughly. The most effective method to achieve this is with a pressure washer utilizing a mild detergent mixture. Allow the wall to dry enough so it isn't dripping wet, but don't allow it to dry completely. Stucco sets best when the surface is moist and weather conditions are cool and humid. The first coat is a scratch coat of only three-eighths of an inch thick. Scratch coats are kept very coarse to help the finish bind and set properly. The coat should set with the finishing coat applied after it dries. The finishing coat should not be more than a quarter of an inch thick.

Considerations

When applying stucco over stucco there are a few things to consider. There is the original thickness of the wall, and that you are going to add to that thickness by spraying new stucco on it, which can lead to minor or major issues. A major issue can be a property line issue if you have neighbors who don't want your wall to cross, even an inch, over your property line. Another issue is being able to fully assess the wall for damage in the future. You may not be able to see the decay or structural damage if you apply a new layer of stucco over old stucco. While these issues are rarely major concerns, they are things to consider when resurfacing your existing stucco wall.

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Ask the Builder: Stucco Walls

Cement: Stucco Frequently Asked Questions

Ejecting the chemical or cleaning solution at a high pressure will only waste your stuff. But if you have a pressure adjustable wand, you can apply the agent at low pressure then go for a higher pressure. The results will certainly be better