Caulk instead of grout on granite porch and steps?
So we have two porches of large tumbled granite slabs, with polished granite risers and side trim. We are built on clay soil. Every few years the slabs crack and we need to get a few replaced. The guy who did this work retired. We couldn’t find anyone else to do it – tile guys said no, stonemasons said no.
Finally I found a guy who mainly does this sort of outdoor tile work. By now the whole thing was crumbled and dangerous. He created a beautiful drawing and said the problem we moisture getting in, not the shifting ground underneath. Replaced the steps made sure they were leveled the right direction. So far so good, although a couple of the riser tiles were cut about 3/4 of an inch short.
He taped everything and I assumed the next step would be dark gray sandy grout. Instead, yesterday his guys caulked the entire expanse of tile with a light grey plasticky looking caulk. Including a generous slop of it to fill out the gap where the tiles were short.
Replies
The tiling standard is - Anywhere there is a change in plane, the joint is caulked. Everywhere else, it is grouted. So, all vertical and horizontal corners get caulked. This is because grout cracks at changes in plane and may lead to water infiltration.
Caulk and grout joints should be uniform throughout. Whether caulk or grout, one joint shouldn't be 1/2" wider than all others. I suspect the stair risers aren't equal if the tiles were cut the same height. That's would be a trip hazard and against Code.
Frankie