Joined: July 2004
||Posted: 27 Aug. 2019,12:55
Fig 7 (p15) of Doc H B.Regs requires 50mm all around, and then fill with compressible sealant.
As ever with B.Regs, it comes down to what Building Control will accept, so you would need to have a chat with them.
When you think that, only 20 or so years ago, the "through" pipe was always rigidly embedded in the wall with mortar or concrete, and then linked either side with short rockers (300mm or so), and I've never yet seen a failure, so why all this fuss about compressible fillers and gas protection?
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