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Paul Barker

Quote:

Originally Posted by andrewpreece

"Paul Barker" wrote in message
...

andrewpreece Wrote:
"Ed Sirett" wrote in message
news On Sun, 13 Feb 2005 12:44:21 +0000, Lobster wrote:
-
andrewpreece wrote:-
I was wondering whether gas pipes can be run behind plasterboard
studding? I know that gas pipes penetrating a cavity wall need to
be
sleeved, with one end vented, but am not aware of such a requirement
for use within studding. Of course the consequences of a gas leak
there are not so severe - a gas leak into a cavity wall could be
disastrous, whereas a gas leak into a studding wall would not cause
stuctural collapse ( if ignited ), but I thought I'd ask about any
regs/best practise,-

According to Ed Sirett's FAQ
(http://www.makewrite.demon.co.uk/GasFitting.html)

"Pipes may be run inside partition walls provided they are corrosion
protected with anti-corrosion tape" (although I don't know whether
that
refers to stud partitions or solid brick ones? Not sure why you'd
need
the tape inside a stud partition?)
-
I have perhaps over stated the case here. The pipe will need
protection
where it goes through the p/board. Also you need to make sure that
the
pipe is adequately supported, bearing in mind that the p/board will
not
hold a pipe clip very well.
-
Thanks folks,

Andy.

Gas pipe inside timber frame construction walls should be a/ run
vertically within purpose designed channels or ducts (i.e. a wooden
backing batten and two wooden side battens against which the
pasterboard buts), b/ adequately secured to studding, c/ have a minimum
number of joints with no compression fittings, d/ be protected where
appropriate from mechanical and corrosion damage. Do a tightness test
before you wrap and conseal the pipe.

A gas leak in any enclosure would be disastrous as the explosive
mixture of between 5 to 15% gas to air (though combustion usually takes
place at 9% under test) is soon reached. It is preferable to run gas
pipes outside, and not ideal to run it inside stud walls, but vanity is
such an important criteria in use guys' homes these days.

Paul

Thanks for that Paul: I had already figured on solder joints, and the usual
gas-tightness tests with that aerosol soapy spray stuff that is designed
for this purpose. Ditto for protecting against mechanical and corrosion
damage,
and secure mounting every x inches ( I forget the figure, I'll have to look
it up ).
I also know about keeping it away from electricity cables ( at x spacing,
again I
will look it up ).

The stuff about putting it in channel is new to me, I shall look into that.
The
problem is that part of the run needs to be horizontal, and that means any
channel can butt to the plasterboard as the studding frames are in the way.
I had already decided to ventilate the plasterboard studding, with vents
down at base
level and up above the kitchen units to keep air ventilating ( help prevent
damp
too! ).

The previous owner buried the gas pipe in cement render - you should see the
state of it - bright green!

Andy.

Cement attacks copper pipe whether gas or water, it should have been wrapped.

Corgi rules are quite clear that runs in stud walls can only be vertical, horizontal runs shouldn't run inside the wall. Horisontal runs in chases are also frowned upon.

15mm copper pipe clip minimums are 2m vert 1.5m horiz and for 22mm 2.5 vert 2 horiz. Most people clip more frequently than that anyway because it's not particularly secure at that. Pipe mustn't touch the mortar in a bare brick wall because of the attack from the cement in it.

Distance from electic cable is 50mm by prefernce but 25mm can be used, closer than that may be OK if you wrap the pipe with insulating tape where it comes close to electric cable or terminals/connections.

Very safest route for gas pipe is outside the house and straight through the wall into where it is needed. Any gas escape is imediately dissipated into the atmosphere where it presents no risk of explosion.

Explosion is your enemy with natural gas. Stud walls present a beautiful opportunity for the gas air ratio to reach explosive limits.