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By GSB
#8487
Hello Every one
I am doing my bathroom removed the tub and putting recess shower tray . I have two bathrooms next to each other. bathroom one drains comes in bathroom two and then goes in soil pipe as soil pipe is boxed in bathroom 2 corner. check
picture 1 and 2
I added boss connector to soil pipe which is about 45 cm below the roof to drain both bathroom separately. used 40mm pipe.
check picture 3 and 4
The drain pipe of shower tray is running around 1meter before turning 90 degree downwards parallel to the soil pipe and connected to the soil at around 40 cm below.

my concern is siphon of the pipe when they drop 90 degree downwards. please let me know if I need to vent there 40 mm pipes .
Thank you
Attachments
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Picture 2.jpeg
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picture 3.jpeg
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picture 4.jpeg
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Last edited by GSB on April 13th, 2021, 10:35 am, edited 3 times in total.
User avatar
By REDSAW
#8491
No, should only need the one to stop back-flow into shower tray as that would be the escape point otherwise drawing the seal from its waste then stinking out the bathroom every time bath is taken. However, you dont want blockage at the 'y' section either otherwise bath will empty into shower tray- all of it. therefore fit a one way trap or inline seal as well. ideally the shower waste should exit on its own to drain usually to an air brake hopper outside.
By GSB
#8492
REDSAW wrote:
April 13th, 2021, 11:36 pm
No, should only need the one to stop back-flow into shower tray as that would be the escape point otherwise drawing the seal from its waste then stinking out the bathroom every time bath is taken. However, you dont want blockage at the 'y' section either otherwise bath will empty into shower tray- all of it. therefore fit a one way trap or inline seal as well. ideally the shower waste should exit on its own to drain usually to an air brake hopper outside.
Thank you, that was of great help.
I have to pass 40mm pipe through joist. Joist which is 19.5 cm . My question can a i drill 40mmhole?
User avatar
By REDSAW
#8493
GSB wrote:
April 15th, 2021, 11:48 am
REDSAW wrote:
April 13th, 2021, 11:36 pm
No, should only need the one to stop back-flow into shower tray as that would be the escape point otherwise drawing the seal from its waste then stinking out the bathroom every time bath is taken. However, you dont want blockage at the 'y' section either otherwise bath will empty into shower tray- all of it. therefore fit a one way trap or inline seal as well. ideally the shower waste should exit on its own to drain usually to an air brake hopper outside.
Thank you, that was of great help.
I have to pass 40mm pipe through joist. Joist which is 19.5 cm . My question can a i drill 40mmhole?
yes you can, but not if its going to be notched. then it depends on the joist type. you need to be aware on the building regs docJ for correct drilling and notching of joists which has had a bit of a rejuvination at the moment, (was on my exam resits last week lol)
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