Exterior Rubber Seals

I inspected a new construction yesterday that had stucco front and hardi on the back and sides. This was the model home so there were little feature and amenity signs one of which boasted about rubber seals at the stucco joints. The joints were about 1 1/2 inches wide and the seals felt like a polyurethane material, similar to Vulkem. Has anyone come across this? Any issues down the road?

Interesting, and no I haven’t myself. Metal expansion joints, yes.

But…1 1/2" Poly or similar expansion joints? (if I understand your meaning)

Cosmetically… what does that look like? Pics?

I’m curious if someone else has seen these. Is it an expansion joint that someone filled? Even at that, i’ve not seen expansion joints on hard coat stucco that were nearly that wide.

Pics would be cool.


I didn’t take pictures but it looked and felt like polyurethane. It looked proffessional and by design. I don’t know how thick it was and there was no reason to call it out. We don’t get a lot of stucco in the PNW so I may not see this for a year or more. I’ll have to ask around. If I find something I will post it.

What color was this material?