In article ,
Huge writes:
On 2007-02-23, John Rumm wrote:

The purpose of the sleeve is to contain any escape of gas such that it
is vented outside the building (preventing corrosion of the pipe is a
welcome fringe benefit, but not the primary motivation).

Pity whoever installed the bottled gas system in my house didn't read
this... The bottles are outside and the 15mm copper pipe just comes
straight through the wall. No sleeving.

Just walk down any road of houses, and you'll see a number of
tell-tale signs of sealed system boilers, i.e. a flue terminal,
pressure relief pipe, and gas pipe all going through the wall
within a few feet of each other. It's remarkably rare to see
the gas pipe is actually sleaved, yet these will nearly all
have been installed by CORGIs. I often wonder why this particular
regulation is so universally ignored by the profession.

Needless to say, if you look at my own DIY installation, they're
all sleaved (even the water pipes, so as they exand and contract,
they don't eventually rub a hole through the pipe), although I
must admit I didn't bother with the PRV outlet.

--
Andrew Gabriel
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