Unused chimney - ventilation ?
Michael Lake
In message <5sv0uq$6...@beulah.demon.co.uk>
ric...@beulah.demon.co.uk.nojunk (Richard Robinson) writes:
> I've recently bought, and moved into, a fairly normal Victorian stone-built
> terrace house; and now I'm running around trying to find out the state of
> everything and wondering what to do about it all ... :) and I'm not
sure about
> one of the chimneys, I wonder if anyone can advise me ?
> One of the bedrooms used to have a fireplace, with a chimney running up
> the outside wall. This has been completely closed up, both at the bottom
> and at the chimney-stack. There are no air-bricks or other ventilation,
> just a closed off dead space.
> The iinside wall where this is has been damp, but I'm not not yet sure
> whether this is related, since the roof was letting water in above it as
> well. The roof has been dealt with and the wall is much drier, but it hasn't
> rained much since, so it's hard to tell. So my questions are;
> 1) if the wall remains damp, presumably the flue needs ventilating - would an
> airbrick or two at the bottom be sufficient, or should I think of opening it
> up at the chimney stack too ?
> 2) if the wall seems to dry out, would it be okay to leave this flue as it
> is, or will it be likely to give problems anyway if I don't ventilate it ?
> Thanks in advance.
>
Richard
It is always best to vent an unused chimney.The best way is to put a
vent low level in the bed room,and put a metal ch cowel on top of the
chimney stack,this will give a good flow of air and will cure any
damp related to the chimney
Mick
Frank Duffy
In article <33F884...@spamnewbridge.com>, "Derek Uttley, Nepean,
Canada." <dut...@spamnewbridge.com> writes
>
>Wouldn't it be best to have the vent on the outside of the house into
>the bottom of the chimney space? This would eliminate losing precious
>heat up an unused chimney during the winter heating season. Also, will
>avoid odours from chimney being introduced into bedroom.
>
Hi,
Just caught this one and thought I'd add a bit.
I'd say that it's better to let the chimney ventilate the living space
because. I produces a cery low level of ventilation. Virtually all the
heat will be lost to the structure of the building (so it isn't
technically wasted) But mainly because it is better to ventilate your
home. It reduces condensation and gives a generally better indoor
environment.
--
Frank Duffy
Derek Uttley, Nepean, Canada.
> >
>
> Richard
> It is always best to vent an unused chimney.The best way is to put a
> vent low level in the bed room,and put a metal ch cowel on top of the
> chimney stack,this will give a good flow of air and will cure any
> damp related to the chimney
>
> Mick
Wouldn't it be best to have the vent on the outside of the house into
the bottom of the chimney space? This would eliminate losing precious
heat up an unused chimney during the winter heating season. Also, will
avoid odours from chimney being introduced into bedroom.
D.
Derek Uttley, Nepean, Canada.
Frank Duffy wrote:
>
> In article <33F884...@spamnewbridge.com>, "Derek Uttley, Nepean,
> Canada." <dut...@spamnewbridge.com> writes
> >
> >the bottom of the chimney space? This would eliminate losing precious
> >heat up an unused chimney during the winter heating season. Also, will
> >avoid odours from chimney being introduced into bedroom.
> >
>
> Just caught this one and thought I'd add a bit.
>
> I'd say that it's better to let the chimney ventilate the living space
> because. I produces a cery low level of ventilation. Virtually all the
> heat will be lost to the structure of the building (so it isn't
> technically wasted) But mainly because it is better to ventilate your
> home. It reduces condensation and gives a generally better indoor
> environment.
> --
> Frank Duffy
there for 25 years), ventilation was never a problem. The various gaps
in doors and windows and single glazing helped keep it cool in winter
and warm in summer! (My first winter in Canada was my warmest, even
though it gets very cold (-20 deg C) and I live further South than you
do) Houses here are built from wood with 6" thick insulated walls with a
layer of brick or aluminium siding on the exterior (typical). Double
glazing is standard and oil or gas powered, forced air central heating
is normal. Fire places are not the norm, but where they are installed,
they tend to have glass doors and a vent to allow air in from outside to
feed the fire. This way one is not pulling warm air from the living area
to feed the fire. Even so, one can still feel the additional movement of
air towards the fire. Hence my suggestion of having ventilation for the
unused chimney provided from outside. Agreed, the movement of air would
be more noticeable when a fire is in the fireplace, but if one has
another form of heating in the room, I would aim at keeping it in the
home rather than trying to heat the outside. Ventilation should be
available from other leaky sources.
D.
Frank Duffy
In article <5talds$3...@beulah.demon.co.uk>, Richard Robinson <richard@be
ulah.demon.co.uk.nojunk> writes
>
>But the chimney itself ... (excellent nodename there, Frank) - I'm kicking
>myself.
Hmm. Thanks - shows professional interest you see :)
>There was a scaffold up a few weeks ago, when the roof was remade,
>I should have broken open the top of the chimney-stack then, but I got
>overloaded, too many things to think about. I wonder, if I put an airbrick
>in the bottom of the chimney, would that maybe produce more damp than leaving
>it as it is (if I wait to do the top until there are more jobs to do up
>there) ?
It would be better than bricking it up solid and leaving the top open!
>
>Does any of this have implications for the working of the other flue, which
>will have a gasfire burning in it ? I don't have much idea of the physical
>condition of either of these flues (but I do have a bloke coming to do a
>smoke-bomb test and overhaul the fires, in a week or two. I hope).
It could have a significant effect. If the other flue is used for a gas
fire then it is possible, if the masonry between the two flues is porus
or faulty, for the fumes to be drawn down into the other room. This is
a dangerous situation. If a propper smoke test is done this will show
up any faults.
>
>Maybe the best answer would be to put a fire into it.
>
>
Only if it is structurally sound. As I said, a smoke test will show
this up. If you want specific advice before or after the bloke does the
smoke test you can e me in private.
--
Frank Duffy
Personal email to fr...@chimney.demon.co.uk
at work...
ISOKERN - the safety chimney fdu...@isokern.co.uk
http://www.isokern.co.uk
Paul Burridge
In article <33fddf32...@news.demon.co.uk>, George Hockey (geo...@tracerbs.demon.co.uk) writes:
>If the plaster remains damp after you have corrected the ventilation
>and any sources of rain-water penetration, it is probable that the
>flue was inadequately swept prior to being closed off.
>Soot contains hygroscopic salts, a residue from solid fuels, and just
>like rising damp, if it becomed damp may cause the salts to migrate
>through the plaster and decorations.
>If so, and the plaster dampens periodically as humidity changes, then
>as with rising dampness, you will need to replaster.
>Avoid lightwieght Gypsum backing plasters at all costs. Instead use
>either Limelite Renovating Plaster or Washed Sharps Sand and Cement
>incorporating a salt inhibitor, such as when replastering after a
>remedial damp proof course.
>This will block the hygroscopic salts in the walls.
>If feasible, you should check the flue anf if not adequately swept,
>consider doing so.
Before going to these lengths, it might be worth trying Polycell
Stain Block. I've found it very effective at holding back this
kind of problem indefinitely.
--
audi alteram partem
Frank Duffy
In article <42...@osiris.win-uk.net>, Paul Burridge <burr...@osiris.win-
uk.net> writes
>
>Before going to these lengths, it might be worth trying Polycell
>Stain Block. I've found it very effective at holding back this
>kind of problem indefinitely.
>
structure. It'll find it's way out somewhere - an if it doesn't it
might start to smell.