How to Install a Drain Strainer to Catch Hair

Drain strainers are the simplest line of defense against the hair that ends up clogging your bathroom sink or shower. They sit right at the drain opening and catch everything before it goes down the pipes. Installing one takes minutes, saves you from pulling out a plumbing snake later, and works whether you're retrofitting an old drain or replacing a worn-out strainer that's finally given up. The key is getting a snug fit so water still flows freely but nothing solid makes it through.

1. Clear the Old Drain First. If you already have a strainer, unscrew or unclip it from the drain opening. Pull it straight up and out. For pop-up stoppers in sinks, you may need to remove the stopper rod underneath the sink first by loosening the horizontal screw on the rod's collar. Clean out any hair or debris sitting in the drain opening with your fingers or a small brush.
2. Find Your Exact Drain Size. Drain openings come in standard sizes: 1.25 inches (small sink drains), 1.5 inches (most standard sinks), and 2 inches (large kitchen sinks and tub drains). Measure your drain opening with a ruler or bring the old strainer to the hardware store. Buy a strainer designed for your specific opening size. Basket-style strainers work best for hair capture; avoid flat screens that clog quickly.
3. Clean the Drain Opening. Wipe the inside edges of the drain opening with a cloth to remove any old sealant, corrosion, or residue. For metal drains, a little white vinegar on a cloth cleans the rim quickly. Dry it completely with a clean cloth. A clean, dry surface ensures the new strainer sits tight and the gasket seals properly.
4. Seat the Gasket and Basket. Most strainers come with a rubber gasket that goes down first. Place the gasket flat inside the drain opening, centering it. Set the strainer basket on top, aligning any tabs or notches with the drain opening's shape. Press down firmly so the basket sits snug against the gasket. The basket should sit just barely proud of the sink surface—not flush, not sticking up.
5. Tighten Firmly, Not Hard. From underneath the sink (or from above, depending on your strainer type), thread the locking ring hand-tight over the strainer body. Tighten it clockwise with a basin wrench or adjustable wrench until snug—not gorilla-tight, just firm enough that the strainer doesn't twist or shift when you tug it. If your strainer uses a set screw, tighten it with an Allen wrench or screwdriver until the basket is held solid.
6. Verify the Seal. Run water into the sink and watch for leaks where the strainer meets the drain rim. If water seeps out, tighten the locking ring a quarter-turn and retest. Once it holds, let water run for 30 seconds to confirm the strainer basket doesn't back up water. If the gap between the strainer rim and sink surface is visible, apply a thin line of silicone caulk around the top edge for a finished look (optional but recommended).
7. Empty Weekly, Replace Yearly. Remove the strainer basket once a week and empty the hair into the trash. Rinse it under hot water and replace it. If the basket gets crushed, cracked, or the gasket hardens and stops sealing, buy a replacement basket or a full strainer assembly. Most last 2–4 years before degradation begins.