Noisy Shower waste when flushing the toilet?

[johnnyuk]

Hi All

As part of an insurance repair, we've had a new shower tray & waste fitted.

Ever since, when we flush the loo, there's a gurgling from the shower waste.

We've never heard it before. When fitting the shower waste, the plumber said the immortal words: "I've never seen a waste like this before!"

Is the noise expected / normal? We have run the shower to fill the waste trap with water. Is the issue with the toilet vent or bad plumbing?

Thanks!

John

 

[MarineBob]

I'm not an expert but to answer your questions, yes and yes. If the problems started with the repair that's certainly suspect. Simple case could be a clog but seems like venting is not right

 

[CACJL]

Hi All

As part of an insurance repair, we've had a new shower tray & waste fitted.

Ever since, when we flush the loo, there's a gurgling from the shower waste.

We've never heard it before. When fitting the shower waste, the plumber said the immortal words: "I've never seen a waste like this before!"

Is the noise expected / normal? We have run the shower to fill the waste trap with water. Is the issue with the toilet vent or bad plumbing?

Thanks!

John

When toilet waste descends the the down pipe it creates a vacuum behind it, sucking the water out of the shower water trap. There needs to be ventilation upstream from where the shower waste joins the toilet waste pipe to relieve the vacuum.

 

[Sargan]

Hi All

As part of an insurance repair, we've had a new shower tray & waste fitted.

Ever since, when we flush the loo, there's a gurgling from the shower waste.

We've never heard it before. When fitting the shower waste, the plumber said the immortal words: "I've never seen a waste like this before!"

Is the noise expected / normal? We have run the shower to fill the waste trap with water. Is the issue with the toilet vent or bad plumbing?

Thanks!

John

There should be a vent on the pipe to prevent this -ve pressure acting as a siphon on your shower waste. An easy option maybe to add a durgo valve upstream of where the waste connects to the stack. There are pipe layout design rules that prevent this - often ignored to get easy pipe connetions.

 

[Yorkieguy]

Conventional good practice is for toilets wash basins, shower trays and baths to each have separate waste pipes which are individually 'tee'd' into the vertical vented soil pipe. Sometimes the soil pipe will be external to the building, sometimes, internal. The 100mm (4") pipe with a vent on the top above the gutter height of the building. If plumbed correctly, whether the washbasin or bath is emptied, or the toilet is flushed it will have no effect on any other item such as the shower tray waste. It sounds to me as though the shower tray waste pipe has been 'tee'd' into the toilet waste and that when the toilet is flushed, it creates a partial vacuum which partially pulls water out of the shower trap. ( If dome correctly, it's OK to tee a shower tray into a bath or basin waste pipe, but nothing should be tee'd into a 4" toilet waste pipe.

If after several flushes the shower trap is sucked empty, you'll the get foul smells into the shower rising from the empty trap. Your bath (if you have one) will have a low level bath trap, the wash-basin will have a 'P' trap amd your shower tray will have a 'bottle' trap.

If it never gurgled before, that suggests that in fixing the new shower tray, the waste pipe arrangements have been altered in a detrimental way. That's just speculation on my part, but the fact is, that nothing else should be 't'eed' into the toilet waste pipe. You'll see a descriptive diagram at this link to make clear how waste pipes should be configured:

https://www.marleyplumbinganddrainage.com/media/1190/soil-waste-design-installation-manual.pdf

Hope that helps.

Good luck with it - you've had quite enough hassle sorting out the insurance claim and getting the work done.

David.