How to Seal a Drain in a Fiberglass Shower Base

  • 2-3 hours
  • Intermediate
  • 65-100
What You'll Need
Putty knife
Silicone caulk
Plumbers putty
Replacement parts
Channel locks or pliers
Ball of paper

A drain in a fiberglass shower base is easy to seal during the installation of the shower pan, but the procedure may be a bit complicated when resealing it for repairs. Shower drain leaks are caused by a variety of reasons, including worn out rubber gaskets, washers, and gaps in the silicone caulk or plumber’s putty.

Step 1 - Remove the Shower Strainer

The shower drain connector is part of the drain assembly that connects to the drain pipe. It contains the drain body, the strainer, the rubber gasket, and washer. In order to seal the fiberglass shower base properly, this device has to be checked for sealing efficiency.

To remove the strainer and access the gasket and washer, loosen the screws securing it to the connector. If the strainer does not have screws, use the flat edge of a screwdriver to pry it off. Be careful not to drop the screws into the drain. Plug the drain hole with a ball of paper to make sure.

Step 2 - Remove the Gasket and Washer

On the internal part of the connector, there should be a metal washer securing and compressing the rubber gasket to ensure a good seal. Remove the washer by turning it counterclockwise until it loosens. Inspect it for any signs of damage. Pull out the rubber gasket beneath it, using a flathead screwdriver. This gasket wraps around the drain pipe and prevents water from leaking. Check for any sign of damage. If the washer or gasket is worn out or torn, purchase a replacement.

Step 3 - Remove the Drain Body

Loosen the sealant under the flange of the drain body with a putty knife. Use channel locks or a pair of pliers to turn the drain body counterclockwise and loosen it from the fiberglass shower base. Remove the entire connector from the drain hole.

Step 4 - Clean the Sealant

Remove any bit of silicone or putty around the joints to prepare for resealing. Check the threads on the drain connector and remove any sealant still sticking onto the surfaces of the flange. Clean the drain body and the joints, and purchase necessary replacement parts from a local plumbing store.

Step 5 - Reinstall the Connector

Before reinstalling, ensure that the surfaces around the drain pipe and the drain hole are clean and dry. Insert the rubber gasket into hole in the drain body and around the drain pipe. Use a screwdriver to push it further down until it sits flush with the opening of the drain pipe. Insert the metal washer and turn it clockwise until it locks into position.

Mold plumber’s putty into a ring and fit it into the undersides of the flange on the drain body. Insert it into the drain hole and turn it clockwise to tighten. Wipe off any excess putty. Remove the ball of paper and reinstall the strainer on top of the connector.