Drop-In Bathroom Sinks and Drain Strainers

Drop-in, undermount or semi-recessed: how the basin sits

A drop-in, or self-rimming, sink has a rim that rests on top of the countertop, making it the easiest to fit and the most forgiving of cutout errors. An undermount basin hangs below the counter and needs a solid, sealed edge such as stone or quartz. A semi-recessed basin sits partly in the counter and partly above it. Use the maker's cutout template, check the basin depth against the cabinet, and confirm the faucet hole layout, since three-hole and no-hole basins suit different faucets.

Drains, strainers and overflow: what fits what

A basin with an overflow hole needs a drain assembly that connects to it, while one without needs a no-overflow drain, and mixing them leaks or leaves the overflow useless. Strainers and hair catchers are sized to the drain opening and rim: a listing might give a 2.25 inch rim or a 4.4 inch basket, so measure the opening before buying. Mesh, chain mail and stainless steel catchers trap hair, and stainless resists corrosion. Floor sink baskets fit square floor drains in utility rooms rather than vanity basins.

Questions about Drop-In Bathroom Sinks and Drain Strainers

Can I swap a drop-in sink for an undermount?

Only if the countertop suits it. Undermount basins need a solid-surface material with a finished, waterproof cutout edge, such as stone, quartz or solid surface. Laminate counters have an exposed core that swells, so they normally take drop-in basins.

Do I need a basin with an overflow?

An overflow hole lets water drain if the faucet is left running with the stopper closed, which helps prevent spills. Some designs omit it, so buy the matching drain type and check that the basin's drain hole diameter fits the assembly.

How do I seal a drop-in sink to the counter?

Run a continuous bead of mildew-resistant silicone sealant under the rim, set the basin in place and press it down. Wipe away the excess, and leave it to cure before using water. Clips beneath the counter hold some basins, so follow the maker's instructions.