Cast iron stacks scale shut over sixty to eighty years. One slow drain is a clog. All of them slow, with gurgling from a fixture when another drains, is the stack. A camera inspection tells you whether it is scale, a belly, or a break before anyone quotes you.

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
• 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
• Stain on the ceiling directly under a bath
• 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.