On Wed, 03 Mar 2004 07:15:52 -0800, Mathew J. Newton wrote:

Hi everyone,

I have a disused chimney/flue which, whilst blocked off (vented) at
the bottom, has an open pot at the top. I have been advised that this
could allow rain (and animal) ingress thus I thought I would take
advantage of my next door neighbour having scaffolding up to wander up
there to fit a suitable cap. The one I had in mind is the 'C-Cap' for
£20 as detailed at:

http://www.fluesystems.com/cowls/info/ccap.htm

Any comments on this choice? It seems perfect for the job, not to
mention a doddle to fit requiring only a screwdriver (the thought of
going up on the roof is bad enough, wrestling with tools and mortar
keeps me awake at night...).

My main question however is that relating to a suitable cowl for my
lounge chimney which currently has a living flame gas fire (Valor
Urban) installed. Given I'll be up on the roof I thought I may as well
fit another cowl for minimising rain ingress into this flue and it is
my understanding that the difference here (compared with a disusued
chimney) is that whatever cowl I fit must be able to cope with heat
and allow sufficient draw. Thus I had my eye on the 'Brewer Birdguard'
for £25 as detailed at:

http://www.fluesystems.com/cowls/info/birdguard.htm

Two types are listed - one for solid fuel fires and one for gas - the
only difference seemingly being the gas version has a smaller/finer
mesh. At the risk of asking a stupid question which one do I want? I
initially assumed the gas version however I'm sure I may have read
somewhere (here?) that a living flame gas fire requires a greater draw
than a 'standard' gas fire and thus a cowl suitable for solid fuels
should be fitted. Can anyone advise?

I posed the question to the above site and they said that I should use
the gas version as 'the finer mesh meets the gas regs'. This confused
me as my pot currently has no cowl fitted (and thus no mesh at all) so
howcome the larger mesh (solid fuel version) doesn't satisfy the regs?
Or am I wrong to have inferred this?

If the solid fuel version is okay, would this be a better option given
it would allow the gas fire to be replaced with a real fire at a later
date without requiring the cowl to be replaced? My assumed drawbacks
with this version however is that the larger mesh may not be as good
at keeping birds/leaves out...

I would welcome any advice on this issue - feel free to ignore my
specific questions and merely recommend the cowl(s) I should get. I
primarily chose the above two based on cost (i.e. cheapest!) and them
appearing to be 'fit for purpose'.


You might find that for the unused chimney a terracotta terminal whcih
simply drops into the existing chimney pot is ideal and very simply to
fit.

The one with the gas fire requires a terminal approved for such use.
Plain open round terracotta chimney pots (amazingly) are approved.
The terracotta type that drops into the top of the pot are seriously
expensive (about £50+).

Any how youshould in no way fit anything other than an approved
terminal on the gas flue. Since you are modifying the flue you should also
check that after you have added the terminal the gas fire still passes its
required spillage tests as laid out in its manual.

HTH
--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html