Question:
The silicone caulking between the cultured-marble pan and the ceramic tile wall in my shower stall has to be replaced. Is there a special tool for this purpose?
–Gene Ackert, Ramona, CA
Pro Tip: Tom Silva, This Old House general contractor, advises that removing silicone caulk isn’t easy: “There are several ways, but I wouldn’t call any of them easy. Like with a lot of remodeling projects, you just have to get in there and sweat a little.”
Answer:
I’m sure there is, although I’ve never had to use one. I’ve had pretty good luck with a utility knife and a glass scraper with a razor blade. First, slice through each side of the bead with the knife, and pull out what you can by hand. Then, hold the scraper at a shallow angle to avoid scratching the surface, and remove any remaining caulk. Next, scrub the surface with an abrasive pad soaked in mineral spirits to get rid of any silicone residue, which will prevent the new sealant from sticking.
Pro Tip: When working on a This Old House project, Tom Silva sliced away old caulk with quick, sharp strokes of a 5-in-1 painter’s tool and a razor scraper. Note that metal blades can scratch plastic sinks, tubs, and surrounds—use a plastic razor blade instead on those surfaces. Caulk removers can also harm plastic, so proceed with caution.
Buy new mildew-resistant caulk that’s formulated for use in bathrooms, and only apply it to surfaces that are bone-dry. If there’s any wetness, fresh silicone won’t adhere properly.
Pro Tip: As Tom Silva explained on Ask This Old House, silicone can be especially tricky when it comes to recaulking: “With silicone and wood, if you try to re-caulk that joint, it won’t seal to itself. So that means you’ve got to remove all of the old caulking before you can re-caulk it.” He recommends considering an acrylic or polyurethane-base caulking as a replacement, which can be easier to deal with down the road.
