Fixing a Leaking Pipe Joint

Types of Pipe Joints

The repair method depends on the type of joint that is leaking. Common residential pipe joints include soldered copper joints, threaded connections, compression fittings, push-fit connectors, and glued PVC joints. Each type fails for different reasons and requires a different repair approach. Before starting any repair, turn off the water supply and drain the affected pipe by opening a faucet downstream of the leak.

Threaded Joint Repairs

Threaded pipe joints (common on galvanized steel and brass pipes) leak when the thread sealant fails or when vibration loosens the connection. Disassemble the joint by unscrewing the pipes, clean the threads with a wire brush, and apply new PTFE thread tape (wrap clockwise, three to five wraps) or pipe thread compound. Reassemble and hand-tighten, then give one to two additional turns with a wrench. For stubborn leaks, use both tape and compound together for maximum sealing.

Copper Joint Repairs

Leaking soldered copper joints can be repaired by re-soldering, but the joint must be completely dry — even a small amount of moisture will prevent solder from bonding. Drain the pipe fully and use bread (white bread with crusts removed) stuffed into the pipe upstream to temporarily dam residual water. Heat the joint evenly with a propane torch, apply lead-free solder, and let it cool naturally. Remove the bread dam by turning the water back on — it dissolves harmlessly.

Temporary Emergency Repairs

When a pipe joint is leaking and you cannot make a permanent repair immediately, several temporary fixes can minimize damage. A pipe repair clamp (a two-piece metal sleeve with rubber gasket) can stop most joint leaks quickly. Self-fusing silicone tape stretched tightly around the joint creates a waterproof seal for days or weeks. Epoxy putty kneaded and applied to a dry joint surface hardens to form a temporary patch. All temporary repairs should be replaced with permanent fixes as soon as possible.