A drum trap is an outdated piece of plumbing. If it leaks, it may probably be due to corrosion if it is made of cast iron or a crack if it is made of plastic. The best way to repair the leak is to replace it entirely with a p-trap. This type of trap is self-cleaning, eliminating the need to clean out clogs, and is recommended by most local plumbing codes.
Step 1 – Drain the Source of Wastewater
A drum trap is usually used in the drainage system of a bathtub. Before working on replacing the leaky trap, drain the water from the tub entirely to avoid water gushing out of it during replacement.
Step 2 – Locate the Trap
The trap should be visible from underneath the tub—that is, from the ceiling downstairs. If the trap is easily visible, then it should be easy to replace. However, if it is covered by ceiling material, that section of the ceiling should be removed and replaced after repairs. The rule of thumb is to work on the ceiling instead of the floor because flooring tiles are harder to replace.
Step 3 – Remove the Drum Trap
Locate where the trap adapters or connectors are located. That is where the trap should be cut. Use an elevated platform such as a table, a chair or a stepladder to access the trap. Wear protective goggles.
Cut the trap using a reciprocating saw at the points where the pipe adapters on the trap meet the fittings on the drain pipe and tailpiece. The saw should be fitted with a metal cutter. Be careful not to cut the fitting. Allow a part of the adapter to stay on the fitting. Remove the trap. Loosen the adapters using wrenches and remove them.
Step 4 – Install the P-trap
Purchase a P-trap including elbows, extension pipes and pipe adapters as necessary. The P-trap has to be installed to the tailpiece coming from the bathtub. To extend the trap to meet the drain pipe, use elbows and extension pipes where necessary. Insert the male or female adapters (whichever is needed) to the tailpiece and the drain pipe. Measure the needed pipe extension and cut it square. Remove the burrs with a knife and sandpaper. Dry fit all the pieces of plumbing.
Remove everything first. Brush pipe dope on the male threads of the fitting or adapters, and connect the adapters to both tailpiece and drain pipe. Tighten them with wrenches. Clean the pipes first before applying pipe cement on the connections.
Apply PVC cement on all connections between the p-trap, the elbows, extension pipes, and adapters. Place everything in their proper order. Ensure that all connections are secure. Allow the cement to cure completely. Before covering the ceiling, test the connection by draining water into the tub or the source of wastewater. Check for leaks.