The best solution is to entirely remove the sink and re-seal the sink to the countertop. To redo it may damage your granite. Expert Interview. Provides a flexible, weather resistant seal. On average, it will be about 38 in (0.95 cm) wide. But because the rim is raised up above the surrounding countertop, water can spill out onto the countertop. Find the right local pro on Houzz to kickstart your project. If the silicone caulk is old enough and has been failing, it should be relatively easy to pull the sink away from the countertop. Any caulk left on the substrate will prevent new caulk from adhering and may lead to moldy buildup. Peel away the remains and vacuum the joint. wikiHow, Inc. is the copyright holder of this image under U.S. and international copyright laws. Let the caulk remover sit on the caulk as directed by the manufacturer's instructions. Use a razor scraper or a plastic putty knife to scrape all of the residual material off. Start by inserting the blade at the top and bottom of the caulk or against the sink. Most undermount sink manufacturers recommend that you use pure, 100-percent silicone sealant for undermount sink installation. Wipe away excess caulk. With supports as well as caulk I would hope. The best way to remove caulk is through a combination of chemical caulk remover and manual tools. Drop-in sinksare easy to installsince they simply drop, or sit, into the countertop cutout and are supported by a rim resting on the countertopitself. Needless to say, I took an extra day to kill any mold that may have started to grow! The sink was reattached with (2) Sink Straps from Regent Stone Products. Place an empty bucket beneath the drain trap under the sink. On top of this, silicone caulk can become discolored over time. I actually am more comfortable now that I have the grills which "raise" the bottom an inch. Be sure to read the label if you have silicone caulk. The positive reveal IS something I told them to do, so that's right: I would recommend just living with it since it blends in so well. This can allow water to seep into the sink, which can lead to corrosion and a loss of water pressure in the sink. It's nonporous, which makes it ideal for adhering to other nonporous materials such as stainless steel. Also, apply the new caulk to extend beyond the old, onto clean caulk-free surfaces to which it can adhere. Once it's turned black, it needs to be replaced.