I have a vintage home that's over 100 years old. There's a grated drain in the basement that connects directly to the sewer, and from what I've learned, it doesn't have a P-trap. Whenever it rains, I notice some unpleasant odors coming from it, which I suspect is due to storm runoff pushing gases back. I used to pour water down this drain, thinking it would fill a leaky trap. A plumber confirmed there's no trap—just a straight pipe. Since we never use the drain, I'm wondering if it's safe to cover it, or would that lead to a dangerous buildup of gases in the pipe?
2 Answers
Make sure that the drain is definitely not a vent for your plumbing system before covering it. If it’s just a drain, sealing it up with a rubber stopper or cap should be fine, just ensure it’s airtight so no gases can escape.
Yeah, you can cover it with a proper airtight plug to block those smells. Just avoid using any random cover—grab a mechanical test plug from a hardware store for a secure fit. This should help keep the odors out and prevent any gas leaks from coming back into your basement.
Exactly! It’s important to seal it properly. You don't want to risk having trapped gases build up and create a potential problem.
Right, double-check that. It could cause issues if it’s actually part of the venting system for your other plumbing!