Problems with U bends after attic conversion

Wabbit Ears

Hi All

Had an attic conversion over covid. The company no longer exists so I cant chase them for repairs.

One big problem is that, since the attic was done there sems to be a vacuum thing going on where the U bend from the bath gets sucked dry resulting in the bathroom smelling horrible. If I run the bath it is ok for a short while.

Is there a pressure valve or something I can get to cap the downpipe to stop this happening or any other suggestions?

Cheers

Sleeper12

https://www.screwfix.ie/p/osma-waste-valve-white-32-x-32mm/1819K?tc=BI3&gclid=Cj0KCQjw_4-SBhCgARIsAAlegrVQxj88N2F3PJ6HQj7e-sTLxk2kQH9qTHglXoW5vlt4fq5ggM5woJ0aAv5FEALw_wcB&gclsrc=aw.ds

Something like the trap above will keep smells out. You might be able to fit it under the bath. Obviously it's not plumbed correctly. Best practice is to replumb it but the trap above is good if no other options

Wabbit Ears

https://www.boards.ie/discussion/comment/118857548#Comment_118857548

this looks like it'll do the trick. Ill let you know how I get on!! The other option is to tear down several walls in the attic to access the new plumbing and that would be a nightmare