Caulking Out Trouble
Recaulking the horizontal joint between the tub or shower pan and the first course of tiles is the next step after regrouting. A 100 percent silicone caulk is best for sealing out water. Silicone isn't the easiest caulk to use — it skins over quickly and isn't easy to smooth out — but it grips with bulldog tenacity and is very flexible. What's more, it won't tear free from the surface as latex caulk often does, nor will it crack like grout.
To make recaulking less arduous, buy a small squeeze tube of silicone ($4). It's much easier to control than a cartridge in a caulking gun. Cut the tip of the tube at a 30-degree angle, making sure the opening is as wide as the joint. Squeeze the caulk into the joint (photo below, left), but be careful not to overfill it. Apply 10 to 12 inches of caulk at a time, and only enough to bring the joint out flush with the tile. Then quickly smooth the bead with the tip of your finger before a skin forms over the surface. Squeeze in another short bead and repeat the process.
It's essential to caulk around the shower handle and tub spout. Remove the shower handle by prying off the decorative cover with a thin-blade screwdriver. Then back out the retaining screw (photo above, right) and pull off handle. Remove the trim plate and apply a continuous bead of silicone caulk around its rubber gasket (photo below, left). Press the plate back into position and replace the handle. Then apply a thin bead of caulk all the way around the tub spout (photo below, right).
Don't use the shower for two to three days so the grout and caulk can cure. If you must use the shower you just worked on, tape up plastic sheets to keep the walls dry. Once everything has cured, apply a liquid silicone sealer ($3.50) to all the grout joints, both old and new (below). The sealer will make the grout more water-resistant and less porous so it lasts longer and stays cleaner.
