What is the best way to fix hair-line stair-stepping cracks in your stucco with concrete blocks?

Construction Walls
1

I have a chimney that has cracks though the stucco from top to bottom, what is the best way to fix this?

1 Like
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I fix a lot of this here in Vegas…

I am not sure where you are but our Las Vegas ground has an abundance of  salt which forms Subflorescence, when too much water and salt is wicked up and absorbed into the concrete foundation, it will collect underneath the "creamed", finished layer of concrete. This salt will crystallize, creating pressure on the top layer of concrete and climb our walls which will lead to spalling, and the degradation of the face and expulsion of stucco from it’s surface..

Depending on how your fire place was made...we could speculate... the internal surfaces have become moist..... it will begin to degrade and corrode. As it does so, it will also create off gassing which puts pressure on the concrete and stucco, leading to spalling and cracking.

Here is the part where you need a cup of Coffee or Tea!!!....The Thermodynamics and moisture must be curtailed to stop efflorescence, spalling and concrete surface degradation.  Capillary Action transports liquids through porous solid by way of surface tension acting in the capillary pores.  Concrete bricks can wick over three pounds of water per square foot per day.!!! No stucco or paint  can stick to any surface with that much moisture. Closing those capillaries is the first step to arresting the destruction of your stucco and concrete.  Hydrophilic densifyers (Green Tek's  PBG7) which is absorbed and utilize water to catalyze and react with stucco and cement particles to produce elongated crystalline structures. These structures physically block pores, cracks, and it sufficiently resists the penetration of water under pressure.  

After you have sealed everything go back and perform the cosmetic touch ups along the cracks....then densidy and seal them as well....

Good Luck!!

Jimmy
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the answer by seemingly straight gives you a good idea where to start… you have to find the underlying cause of why the concrete cracked in the first place… it could be the soil conditions in your area, if there are cracks in other parts of your house, the reason could be the settlement of soil beneath your house, etc.