Waste-and-overflow gasket, not the drain. It only leaks while someone is in the tub, which is why it goes unfound for years. Access is usually from below.

This is most common in homes built before about 1940. Pre-war construction — galvanized supply, cast iron drains, cloth-wrapped wiring, ungrounded circuits.

Related

• Pressure drops at every fixture at once
• Every drain in the house is slow, not just one
• Rusty water only on the first draw
• The main shutoff will not turn
• Sewer backs up in the lowest fixture after heavy rain
• Sewer smell from a room nobody uses
• Hose bib with no vacuum breaker
• Laundry standpipe overflows on the spin cycle

Back to Plumbing.

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Written by Jaylan Jones. I Like To Fix earns a referral fee when a call connects to a contractor. See our business-model disclosure.