Stud thickness for horizontal 110mm soil pipe

[sean1933]

Hi all. 

 

I've come to put up the last stud wall in our house (vaulted ceiling @ 3.8m, not load bearing) and my wife in all her wisdom is now adamant on a new bathroom layout, which moves the toilet to the opposite corner from the soil pipe.  I am mindful that the 110mm soil pipe now has to travel horizontally 2.5m within this wall before it can turn 90deg and go under the floor (there is a steel within the mid span of the room that prevents me from going straight into the pozi joist floor at this point). The room sizes are already getting smaller than ideal so anything I can do to mitigate would be ideal. I had planned for 145 studs to hide vertical soil stack but now its going horizontal I appreciate after 125mm central hole is cut the remaining 10mm either side is clearly insufficient. 

 

Should I beef them up to 195 studs / line with ply (both sides I assume) ? I think someone had previously mentioned a similar issue being avoided with a raised sole plate but for the life of me I cannot find it by searching. I also found some sort of stud shoe but these didnt appear to be appropriate for 4inch pipes.

Or is there an alternative easy solution? 

 

thanks in advance!

[nod]

I put to studs back to back with a 150 cavity Great for soundproofing also 

[Mr Punter]

I guess you could have a pair of, say 220 x 45 joists across the of top of the pipe as a lintel and sheathe with OSB

 

[sean1933]

Thanks both. I really like Punter's idea as it would help keep the wall slenderness down to a minimum which will keep her in doors happy, and I'm pretty sure I have some of that size timber lying around already. 

 

I did consider back to back studs but a +275mm finished wall buildup made me wince somewhat!