Tried polyurethane caulk vs silicone for a commercial storefront job in Cleveland

Honestly, I always used silicone for glass storefronts because that's just what the old guys taught me. But on a job last month at a strip mall on Euclid Ave, the polyurethane was way easier to tool and paint over without that sticky mess. Has anyone else made the switch or am I missing something with silicone's flexibility?

3 comments

3 Comments

king.derek1mo ago

100 bucks says that paint shop on Chester charged you double for the polyurethane and told you it was "commercial grade". Silicone is like that old friend who never calls back but always shows up when you need him, and polyurethane is the new guy who paints over his mistakes. I tried the Sika polyurethane on a storefront on West 117th and it worked fine, but the cleanup with mineral spirits drove me nuts compared to just wiping silicone off with a rag.

robinp722mo ago

Polyurethane definitely beats silicone for painting over, that's for sure.

anthonymurray2mo ago

Polyurethane is great for adhesion and flexibility, but one thing people miss is that not all polyurethanes are created equal for painting over. The single-component stuff from a tube is a lot easier to paint than the two-part or hybrid blends. However, even with the right polyurethane, you still need to wait for it to FULLY cure before slapping paint on it, or it'll peel right off later. Silicone at least has the advantage of being ready to caulk and forget if you never plan to paint it. But for a simple fix where painting is the goal, yeah, polyurethane wins hands down. Just don't expect every brand to behave the same way.