That bit about the vent stack caught my attention—
—I ran into that on a job last month. Weirdest thing: the smell was strongest when it was windy outside, almost like the wind was pushing the odor back down the pipe. Any chance you’ve noticed if the smell changes depending on the weather or if you’ve got a window open? Sometimes those little details point to a venting issue, not just the toilet itself.Sometimes a blocked vent can trap sewer gases and make the whole bathroom smell off.
That bit about the vent stack caught my attention——I ran into that on a job last month.
I get where you’re coming from about the vent, but honestly, I’ve seen “pool smell” in bathrooms more often from cleaning products or even a slow leak around the toilet base than from vent issues. That “chlorine” scent can linger if someone’s using bleach or certain tablets. Not saying venting can’t cause odors, but if it’s always got that pool vibe, I’d double-check what’s being used to clean or if there’s any dampness under the floor. Sometimes it’s not as complicated as a blocked stack.
Why does my bathroom always smell like a pool?
That “pool” smell is a classic head-scratcher. I’ve been called out for it more times than I can count, and honestly, it’s almost never the vent stack—though I get why folks jump to that. Here’s how I usually break it down when I’m troubleshooting:
Step 1: Sniff around (literally). If the scent is strongest right by the toilet or under the sink, odds are it’s not a vent issue. Vents tend to cause more of a sewer gas stink, not that sharp chlorine tang.
Step 2: Check your cleaning stash. Bleach-based cleaners or those drop-in tablets are notorious for leaving that “public pool” aroma behind. Even if you’re not using them every day, residue can linger in grout or under the rim.
Step 3: Look for leaks. A slow leak at the toilet base or under the sink can mix with cleaning chemicals and create some wild smells. I once found a tiny drip behind a client’s toilet that had soaked into the subfloor—smelled like someone dumped a bottle of bleach every week.
Step 4: Ventilation check. If your fan isn’t pulling its weight, moisture and odors just hang around. Quick test: hold up a square of toilet paper to the fan grill—if it doesn’t stick, your fan’s probably not moving enough air.
Step 5: Inspect for hidden dampness. Sometimes water sneaks under vinyl or tile and just sits there... add a little bleach from mopping, and you’ve got yourself an indoor YMCA.
I’m not saying vent stacks never cause weird smells, but in my experience, they’re more likely to make things smell like rotten eggs or something died in there—not like you’re about to do laps.
If you’ve ruled out all the above and still get that pool vibe, maybe try switching up your cleaning products for a week or two. You’d be surprised how much difference that makes. And if you find any mystery puddles, well... time to break out the wrench (or call someone who will).
Hope this helps someone dodge an unnecessary plumbing bill—or at least gives you an excuse to skip cleaning for a bit while you “investigate.”
I get what you’re saying about bleach cleaners, but I’ve had a few units where tenants swear up and down they don’t use any, and that smell still hangs around. Sometimes it’s actually the water itself—city water with high chlorine can leave that pool scent after a hot shower. Not super common, but it happens. Worth checking if the smell gets stronger after running the tap or shower for a while.
Sometimes it’s actually the water itself—city water with high chlorine can leave that pool scent after a hot shower.
Interesting point. I’ve noticed that too, especially in older buildings where the plumbing might hold onto that smell longer. Have you ever checked if the smell lingers in the bathroom even after the water’s been off for a while? Or is it only right after a shower? Makes me wonder if ventilation plays a part, or if it’s just the water chemistry.