I used this to seal the membrane to fundations sprayed with polyurethane. It hold well and doesn't seem to react to the polyurethane, but I think the seal would have been better with sprayed polyurethane because of the irregular surface. I may complete the work with this in the future.

As another reviewer mentioned, this stuff is hard to find, so rather than take the chance of running 1 or 2 tubes short, add them to your original order. I made the mistake of underestimating the # of pins and caulk and had to re-order and pay shipping. What really hurt was stopping my progress to wait for these items. Everything I ordered from these guys is top notch and the pricing is very fair. Don't hesitate to call Larry or the others for advice. They were very patient with this novice who had a ton of questions.

Stuck well to poly vapor barrier and concreate wall. Appears to be a good product. Will know in 5 - 10 years how it holds up.

I ran into concrete block sweating to the point that the foundation tape wouldn't stick. This stuff worked perfectly.

used this to seal around the vents. Put a 4x8x16 solid block in where the vents were after closing them then pushed the backer rod into the gaps about 3/4 inch to seal off air flow then used the cement caulk. Didnt order enough so used a water noodle of the kids for the last 4 vents. You can improvise but backer rod is inexpensive and works great.