Thread: Cracks in Stucco - To caulk or not to caulk?

I inspect in Central Florida and run across hairline vertical and step cracks in masonry stucco on most homes. While these do not usually present a problem during normal rains, what is the consesus during periods of wind blown rain such as in a hurricane or tropical storm? Would you advise caulking the cracks? And if so, would you also say that they need to be painted to blend in with the surrounding wall surface (the reason I ask is once it's caulked, it then becomes a cosmetic issue... right?)? Your thoughts would be most appreciated.

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• caulk that crack says SE

any stucco siding I tell clients to check it annually, fix the cracks by paint or caulkiing, totally repaint once every 6 yrs or so.

I like something like this:

"Properly maintain all exterior surfaces to prevent moisture penetration."

It is not up to us to (necessarily) determine the proper method without taking on additional responsibility. If you tell them what to use and how to do it, you are leaving yourself wide open. Our job is to find and disclose defects and that is a defect. That statement along with a good picture fulfills that obligation.

While looking at your crack(s), the most important issue that comes to mind is ; why did the blocks (joints) crack and are the cracks (blocks) stabilized? Since the stucco appears to be installed on masonry blocks, the cracks are really associated more with the blocks and not with the stucco finish.

Once you have determined if the cracks are growing or are stable, you can concern yourself with how to seal them. If you can't determine if they are stable or do not feel confident in making that call, you should recommend someone who can. Or you can recommend sealing them and monitoring them for future movement. If all you do is seal them, without repairing them, I assure you that they will reappear.

I don't have much faith in a simple caulking, since that is a band-aid and not a repair. You could " paint the surface with something like Thoroseal, but the crack with come through again.

The best way I have ever seen a crack sealed is with hydrophobic polyurethane. Which is injected into the crack (from the middle out). Another way is by V-ing out the crack and then repairing it. Once again, if there is continued movement, they will reappear.

My last and least concern is the aesthetics, in which case any masonry paint will take care of. Unless, if the finish is polymer based. If so, I would recommend an elastomeric paint.

too many cracks there-and are you a stucco expert

and over what seems to be block--i would recommend evaluation by licensed stucco/eifs inspector--if your repair recommendations don't work--you are liable

cvf

Just report what you see. Typical cracks, see it all the time on that type of contruction here. Assuming there is no displacement.

I agree with what Steven posted..... Those cracks are telling you something and that might just be that it is a real crappy stucco coating! Really looks like more of single heavy finish coat over CMU.

Hold on there, fellas.

Those are common CMU/Stucco cracks for our location. No cause for alarm.

The block walls were "sprayed" with a stucco coating/covering, and the cracks appear in the weak spots (windows/doors).

See it all day long here. No need to panic because of that.

Originally Posted by Dom D'Agostino

Hold on there, fellas.

Those are common CMU/Stucco cracks for our location. No cause for alarm.

The block walls were "sprayed" with a stucco coating/covering, and the cracks appear in the weak spots (windows/doors).

See it all day long here. No need to panic because of that.

This is when to panic.

Originally Posted by Paul Kondzich

This is when to panic.

And clearly worse than the original poster's minor issue.

Perhaps there IS no need for alarm, and panic usually accomplishes nothing. But without a closer look at the WHOLE scenerio; I would be hesitant to simply blow it away.

The second set of photos is just one step away from the first, and the next step is what? Condemnation?

I realize that "common" cracks may be very common, but I would also venture to say that at some point in history, the cracks in house # 2 were no worse that those in house #1.

Dom, you stated that you see this type of cracking all day long. Is this because all homes in Florida crack in this fashion? Or is it that some (or even alot) of homes in Florida crack like this? If so... what is the difference between those that do, and those that don't?

Or is it possible that these are initial settlement cracks, and that the building is finished doing whatever it is going to do?

They are initial settlement cracks. My set of pictures are nothing like the first set. In my pictures the inside of the house was moving, as in cracked drywall, windows that would not open etc. The slab was sinking, which you can see from the picture with the straight line crack. The block wall is sinking from the tie beam, which is poured concrete. These houses are monolithic slab, block construction, and a tie (poured concrete) beam on top of the block wall. The hurricane straps are placed in the wet concrete when the tie beam is poured. The trusses are nailed to the hurricane straps, the trusses sit on the tie beam. Everything is concrete, something will crack. I just drove by new contruction house, without the stucco. I will take pictures and post tomorrow.

Steven,

See them on all homes that haven't been painted in the last 90 days.

I would be surprised to not see those cracks on a CMU/stucco house around here.

Dom.

Originally Posted by Dom D'Agostino

Steven,

See them on all homes that haven't been painted in the last 90 days.

I would be surprised to not see those cracks on a CMU/stucco house around here.

Dom.

Dom, I dont think they are picturing the whole structure of the house basically being one piece of concrete. Do you have any DiVosta houses over there? Poured walls. Ive never seen any cracks in those places.

Originally Posted by Paul Kondzich

Dom, I dont think they are picturing the whole structure of the house basically being one piece of concrete. Do you have any DiVosta houses over there? Poured walls. Ive never seen any cracks in those places.

I guess its no different than when I was in the mountains of Colorado and saw my first floating walls, because the basement slab heaved 4 inches every winter.

Step cracks mean CMU block wall. The lattice that goes between each layer of CMU block is probably missing. Even with cement and rebar the wall will shift along the alternating blocks if there is no lattice between them.