Stucco repair question -- in semi-dire need of advice.

[kguttenb]

Hello - I am a homeowner in the San Jose, CA area with a question on a proposed stucco repair and any advice would be appreciated.

2+ year old 3-coat color-integrated cement stucco installation is badly cracked. Mostly many hairline cracks running horizontally and vertically, but also some wider diagonal cracks from penetrations. Original installer said he’s never seen anything like it, and says it’s clear that our house has excessive structural movement.

I hired a civil engineer and a ‘forensic’ construction person to check it out, as well as several other stucco contractors that I bribed into taking a look at it. The end result was that there is no sign the house is exhibiting excessive movement, and although the stucco looks unappealing, it seems to be a serviceable installation with a repair for the most impacted walls which would consist of 1) fill in the larger cracks with a flexible bonding agent, 2) cover all the cracks with mesh/bonding agent and 3) cover with another color-coat.

The question is: an acrylic color coat would work best as it is more flexible than a cement color coat. However, then I would have to get the whole house done as it sounds like acrylic and cement color coats just won’t mesh with each other in appearance. Opinions seem to vary on sticking with cement for the additional color coat. Some felt a few more cracks would appear with concrete than acrylic, but the mesh/bonding agent would still absorb most of the stucco movement telegraphing through. A couple of people thought acrylic was really the only way to go. And for appearances sake we prefer the mottled look of concrete.

I know there is a near religious argument going on about whether stucco should be always/never painted, but we would prefer to leave the stucco unpainted if at all possible.

Any opinions or experiences anyone has would be greatly appreciated.

Thank you,

[Dick Seibert]

Re: Stucco repair question -- in semi-dire need of advice.

I build in your area, better jobs are now going 4 coats to help prevent the cracking, our problem is that in the summer we have hot days and cool nights, that's a great climate to live in, but with plywood or OSB behind stucco it swells up during the day an and flattens out at night causing stucco cracking. I had one case where they put cedar shingles over 3/8" plywood, every morning it was flat, by afternoon there were waves all over the walls only to be flat again in the morning, you can imagine what that does to stucco. Personally I put no sheathing behind my stucco, but you already have it.

I'd patch it and put the 4th coat on but use a cement based stucco, I'm a believer in the no-paint religion (I like that), and acrylic is worse than paint when it comes to sealing stucco up, you may not have any cracks but you may get mold and mildew in the home, to say nothing of dryrot in your walls.

If you want to PM me I'll stop by if it's not too far out of my way.