Waste trap in concrete

[DIY Max]

Hi all, we are replacing a downstairs shower (whole room refit). The old tray was a whopping 20cm height from the floor. The waste outlet in the pic is 3 inches from the floor. The pipe comes outside just above the DPC. Our installer wants to dig and bury the new waste trap/pipe etc in concrete, tank etc and feed the waste into the main drainage system underground somehow. He has assured us there will not be any issues at all with this method and no issue with leaks at all. I am not 100% convinced this is the best option. I initially thought a raised shower tray was the way to go with timber or a raiser kit. Could really do with some advice on options here thank you.

 

[richw]

Well, the trendy modern approach is a lower waste, so you can have a low-profile tray without a step. It's popular.

The plumbing is more practical with a raised tray, but you have the difficulty of supporting them. Chances are, it will flex, which isn't what you want.

 

[DIY Max]

Thanks Richw. Not too fussed on look necessarily but prefer the lower profile. More interested longer term durability and access if needed. Also if there is any kind of issue we just won't know unless it gets very bad etc.

 

[endecotp]

Show us what’s the other side of the wall.

 

[DIY Max]

Will take a pic. It is engineering bricks, DPC. There is also a gutter where the waste water was dropping into. Outlet pipe above DPC. There is also a main drain pipe underneath the room going into the manhole on the other side of the room. It is an extension built about 25 years ago.