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downstairs toilet bubbles when upstairs is flushed

My first floor toilet hasn't been fully emptying lately unless I hold the handle. This morning we noticed that when we flush the upstairs toilet, the downstairs toilet bubbles. We can hear it upstairs. And now, I think I heard it bubbling when my wife took a shower (also on second floor).

Any thoughts on what the problem could be, and if I can fix it or need a plumber?

Re: downstairs toilet bubbles when upstairs is flushed

In my toilet I installed a flapper that has 'timer' on it. It's basically a plastic cup that has holes in it so when the water drains out the flapper closes. No need to hold the handle down, just press it once and it does it's job.

On the bubbling toilet, it sounds like whoever installed it didn't put a vent pipe (or a large enough one) on your downstairs toilet when they did the plumbing. When any water leaves your upstairs it creates a suction, the only place it can get air from is to pull it in from the downstairs toilet. You can either call a plumber or live with it.

Re: downstairs toilet bubbles when upstairs is flushed

Sounds as though this a recent occurrence

Sight unseen I'm guessing the upstairs bathroom is more or less above the first floor bathroom.
If so .... they're likely sharing the main soil stack.

By the sounds of the issue with the main floor toilet not flushing properly sounds more to be an issue with a partial blockage somewhere in the drain pipe close to where this toilet joins the main stack.

The bubbling of this toilet can also be caused by a blockage.
Anytime water from the shower , sink or toilet is flowing down the drain line .... a volume of air is being pushing ahead of it.

When the second floor toilet flushes it's moving a large bubble of air ahead of the discharge down the soil stack. When this hits an obstruction the bubble of air will flow back. If your main floor toilet is the closet fixture to the stack the air will flow back up into the toilet.

If you have a clean out access to the stack in the main floor bathroom .... remove the cap and with a snake try and dislodge the obstruction.

Otherwise if no clean out access you may need to remove the main floor toilet and try to snake the drain.

Just a thought.:)

Re: downstairs toilet bubbles when upstairs is flushed

I agree that there is probably a blockage/restriction below the 1st fl toilet - - - but if nothing happens with that theory, consider going up on the roof, and snaking down the vent-pipe, all the way to the basement.

Good Luck.

Re: downstairs toilet bubbles when upstairs is flushed

thank you guys for all the suggestions. in fact i am so clueless with this things that every time it happens someting like that the oly thing i can do is to call someone

Re: downstairs toilet bubbles when upstairs is flushed

it could also be something as simple as an animal/bird making a nest on the top of the main stack...the bubbling is definitely a venting issue.

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