Stucco cracks around windows

I have been finding many cracks in stucco around windows in my four-year-old community in southern Utah. I believe this is fairly common but can someone explain why this is happening and what the solution is? Do I just apply a clear exterior caulk to prevent moisture intrusion? The ones I have seen are about 1/16" in width or less. At what point (size) is additional action recommended?

My guess would be the different expansion and contraction rates of the varying materials. I would use a paintable, high quality, preferably color-matched caulk, rather than a clear caulk or silicone for this application.

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Thanks Ryan. Are you suggesting I use a polyurethane caulk? I believe the other types are acrylic and silicone.

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For just about everything window, door, or siding related, my go-to is OSI Quad. Especially where aesthetics are concerned.

Beware…lol

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Yes, this stuff can get messy. Don’t try to smooth it with a finger. You best know how to apply it properly right from the tube.

Thanks Ryan for that additional info – big help!

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Phil can help

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Poor window frame/stucco clearance. When installing windows in stucco leave a ¼ inch gap between the window frame and the stucco on all sides, except for vinyl j-channels.
Recommend a licensed caulking contractor improve clearance and caulk.

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Could be lumber shrinkage as it dries out. Some window installation drawings require a foam backer rod and elastomeric caulk around the perimeter.

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Crap workmanship (Stucco), IMO…!!

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https://forums.jlconline.com/forums/forum/jlc-online-expert-forums/exterior-details/32283-expansion-for-stucco-around-windows

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While you are arguably correct, the photo shows how it is done 99% of the time for aesthetics and ease and price. Best practice is a 1/2" gap between the window frame and stucco finish with a casing bead laid in the gap and a 1/2" bead of caulk over the gap. (See Advanced Stucco course) I see a lot of stucco, and have seen the transition between trim and stucco done to best practice…twice.

Agree with Ryan. Caulk (I use high quaility acrylic latex for ease of application) the gap. Regular maintenance will be required. A small, thin bead of caulk does not age as well as the thick bead used in best practice.

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The solution is knowing how to do it right by using a casing bead and sealant.

This is a common mistake when installing doors and windows in brick or masonry like construction materials. You’re supposed to leave a gap 1/4 or 3/8" and fill it with a backer rod (round piece of foam) and caulk over that with some elastomeric caulk like quad or poly seam seal. This would allow for natural expansion and contraction of materials.

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