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Solving Stucco Problems

Solving Stucco Problems


A major problem that many homeowners with stucco homes have is efflorescence. This is the white dust or deposits that mysteriously form on the surface of the stucco. Efflorescence is simply a by product of evaporating water. People in the southwest are plagued with this problem at the bottoms of their houses. The stucco soaks up moisture from the soil which contains dissolved salts. The water evaporates and leaves the salts at the surface. Rinsing with water does nothing. It just drives the salt temporarily back into the stucco. The salts will return!

Efflorescence growing in the mortar of a brick fireplace. PHOTO CREDIT: Michael Hannum

Efflorescence growing in the mortar of a brick fireplace. PHOTO CREDIT: Michael Hannum

This condition can be solved by preventing water from entering the stucco. In the case of our southwestern friends, the stucco beneath grade level needs to be sealed. That way water from the ground can't get in. The entire foundation may have to be sealed to prevent the efflorescence.

Cracking - Random

If you have a cement stucco house with cracks, the cracks may be caused by several different things. If it is a new house, the cracks could be from lumber shrinkage. Older houses that develop cracks can be the victims of soil movement. Southern California houses get their cracks from earthquake shaking. Houses not properly designed can actually crack from wind pressure!

Fixing cracks is tough. To make a permanent repair you must be sure that the house isn't going to move again at that location. That may be a tough bill to fill.

Crack Repair

OK, so you want to fix the crack. Remove all of the loose stucco. I prefer that you do this repair on an overcast, cool day if at all possible. You will need to locate sand that is close to the texture of what your stucco looks like. What? You didn't know sand comes in different sizes? You bet it does.

Buy a bag of Portland cement. Mix the sand and cement together dry. I like a mixture of two parts moist sand to 1 part cement. Remove the dust from the crack and slightly moisten the old stucco. After mixing water with the sand and cement to a mortar-like consistency, fill the crack. Let it set for a few minutes. Using a sponge, brush or trowel, do whatever is necessary to mimic the texture that the original master created. It will take practice, trust me! Patience is everything.

Over the years, I've seen many different spellings of efflorescence. Here's my growing list: effervesce, effervescence, effervescent, effleresants, effloreflance, efflorescence, efflorressance, effluorescence, eflorescence, eflorescents, ellforesce and ifflorescence.

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One Response to Solving Stucco Problems

  1. I have a Portland cement stucco chimney which is forty feet tall . the stucco was applied over red clay and brick and is over one inch thick. I have repaired cracks on chimney in the past and are currently repairing newly developed cracks.i am a stucco tradesman and wondered if saw cut control joints could this help control cracking as the freeze thaw climate is uncontrollable.these joints would then be filled with the proper sealant and profile.or is this for horizontal concrete only.

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