Keeping it Internally Down to a Dull Roar

[ToughButterCup]

It's  internal foul drainage time.

Heard all sorts of dire warnings about getting this wrong. Strong  advice to shove the foul drain straight out of the house and  down an external pipe. - whassa point of a thermal bridge that size I say?   But I do agree: its obvious that internal piping does need extra care.

Here's the schema. And its based on this discussion.

 

I think I need what I think is called 'acoustic drainage'. I wonder whether anyone has any experience in this somewhat delicate area?

 

Should I just get some of Geberit's  Silent-db20 piping? I don't need all that much ...... or is there anything cheaper that just as good?

 

[Russell griffiths]

I think wavin make a silent pipe as well. 

[Oz07]

Presumably you will be boxing in? Can't you just acoustically insulate around outside of pipe within the boxing 

[Onoff]

I'd buy some secondhand acoustic tiles and wrap the pipe in that. My concealed Geberit cistern has these tiles backing the cavity and the mechanism/fill noise is pretty much imperceptible.

 

 

 

My long soil run in the wall is gun foamed in. I know expanding foam isn't supposed to do much in terms of sound deadening but this is v.quiet. I think probably most noise occurs where "stuff" encounters changes in pipe direction and there I've the acoustic tiles at the 90deg bend and the 2 45s are gun foamed.

 

 

Edited February 19, 2020 by Onoff

[Jeremy Harris]

I just wrapped some 100mm acoustic rock wool, left over from lining the stud walls, around our pipe.  I boxed the pipe in with 18mm OSB, with that plasterboarded and skimmed over the top.  Seems to work OK. 

[PeterW]

Those tiles are as cheap as chips. Worth making sure the areas where it changes direction are insulated and preferably very solidly mounted as that is where you will get noise. 

[ToughButterCup]

You lovely people, thank you.

 

I've never put any foul drainage piping together (yet) so - since the piping is internal -  I think I'll do a little pilot project first. Make something out of foul drain piping using Tees and bends and stuff. And I suppose I'd better use solvent weld hadn't I ?

[Onoff]

14 minutes ago, PeterW said:

Those tiles are as cheap as chips. 

 

Mine were 2nd hand off of eBay. Just had a bit of spray glue residue on the back. From a recording studio in Margate if my memory serves me correct.

[joe90]

I lined the lid of my treatment plant with that acoustic foam as the lid acted like a drum, works very well. Like @Jeremy Harris I wrapped rockwall round my internal poo pipe in a ceiling and that works well , I can only hear water noise in the plant cupboard as I did not insulate it there (on my extensive “to do” list)