Replacing a Bathroom Shower Drain

Drains are the unsung heroes of your bathroom, handling water and debris day after day until they eventually corrode or fail at the seal. A leaking shower drain can lead to significant water damage beneath your shower pan, making this one of those repairs you need to handle as soon as you notice standing water outside the shower or damp spots on your ceiling below. Done well, a new drain creates a watertight bond that lasts for years. You are essentially resetting the interface between your drain piping and the floor surface. It requires patience and a steady hand, but it is entirely manageable without calling in professional help, provided you take your time with the cleanup and sealing process.

Pop Out the Strainer. Unscrew the decorative shower strainer or pop it off with a flathead screwdriver. If there are screws, set them aside in a secure container so they don't disappear.
Unscrew the Old Flange. Insert your drain wrench into the throat of the drain and turn it counter-clockwise to unscrew the flange from the pipe below. If the flange is stubborn, use a pair of channel-lock pliers to provide extra leverage from the inside of the drain rim.
Strip the Seal Surface. Scrape away all traces of the old putty or silicone from the shower pan surface using a plastic scraper. Wipe the area thoroughly with denatured alcohol to ensure a grease-free surface for the new seal.
Apply Fresh Silicone. Apply a generous bead of high-quality silicone plumbing sealant to the underside of the new drain flange. Ensure the bead is continuous and unbroken to prevent future leaks.
Seat the New Flange. Thread the new flange into the drain pipe by hand until it is snug. Use the drain wrench to give it an extra half-turn to compress the sealant, but do not overtighten, as you risk cracking the shower pan.
Smooth and Wait. Wipe away the excess silicone that squeezed out around the flange. Replace the strainer and allow the sealant to cure for at least 24 hours before using the shower.