Switched to foam backer rod for my stucco cracks and now I'm getting water behind it

I read all the time that foam backer rod is the way to go for stucco crack repairs because it lets the caulk flex better. Tried it on a crack along my east wall last month and after the first big rain I noticed the stucco bubbling up. When I poked at it water just ran out from behind. Went back and pulled it all out, stuffed the crack with the old school fiberglass mesh and patched with stucco patch. That held fine through the next storm. I guess my cracks are narrower than most people's or something because the foam was just pushing the caulk out too far. Has anyone else had this backfire?

3 comments

3 Comments

paige42721d ago

Nah I actually had better luck with the foam honestly.

sageross21d ago

In my experience this happens when people pack foam too tight and it stops water from draining out.

bennett.patricia21d ago

Oh yeah, I was just reading a camping blog that said the same thing, @sageross. They mentioned that if the foam is too dense, water just sits on top instead of soaking through. Seems like a pretty common mistake people make when they're trying to keep things dry.