My house is a semi built in 1873, from Yorkshire stone.

It is a devil of a job heating it and keeping the heat in.

I'm getting the existing poor quality double glazing replaced next summer, but I
am also considering cavity wall insulation.

I'm not sure how effective CWI is in house such as mine, and also the effect it
has on resisting or promoting damp penetration.

On 05/10/2010 21:19, S R wrote:
My house is a semi built in 1873, from Yorkshire stone.

It is a devil of a job heating it and keeping the heat in.

I'm getting the existing poor quality double glazing replaced next
summer, but I am also considering cavity wall insulation.

I'm not sure how effective CWI is in house such as mine, and also the
effect it has on resisting or promoting damp penetration.

If your walls are two feet thick then they are almost certainly rubble
filled. Such walls have voids but AIUI cavity wall insulation is not
effective. Two feet of wall is a better insulator than 9 inches of wall
but it is not comparable with a modern insulated wall.

If the wall is substantially thinner you will need to establish what
there is between the inner and outer courses. 1873 is early for proper
cavity walls in brick built houses. I would have thought a cavity would
be unlikely in a stone built house of that age but I could be wrong.

On Tue, 05 Oct 2010 21:19:12 +0100, S R wrote:

My house is a semi built in 1873, from Yorkshire stone.

It is a devil of a job heating it and keeping the heat in.

I'm getting the existing poor quality double glazing replaced next summer, but I
am also considering cavity wall insulation.

I'm not sure how effective CWI is in house such as mine, and also the effect it
has on resisting or promoting damp penetration.

Get in touch with the local council environment dept. who will come round
to check whether you are eligible for a grant. Mine has solid (brick) walls
at the front and cavity at the back, but they drilled the wall and found
that the gap is too narrow. (
--
Jim S
Tyneside UK
www.jimscott.co.uk

On Oct 5, 9:19*pm, S R wrote:
I'm getting the existing poor quality double glazing replaced
next summer, but I am also considering cavity wall insulation.

In what way is it poor quality?

I ask because as long as it is a) not rotten b) seals work c) no
howling gales through it d) windows not broken or steamed-up (which
can be fixed) then windows are windows and the money may be better
spent elsewhere...

I'm not sure how effective CWI is in house such as mine, and also
the effect it has on resisting or promoting damp penetration.

.... such as after finding out you do not have a usable cavity wall
(sufficient depth, free from obstructions etc) that you could insulate
on the inside via sticking insulation on the walls or building a free-
standing timber frame inside into which you stuff insulation and
dryline (plasterboard).

The reason I say that is double glazing is quite expensive (payback
period is 50-100yrs over single glazing and even longer if you already
have double glazing), and insulating solid walls on the inside is also
rather expensive. If you DIY it will still be costly re materials,
redecorating etc - but the difference is you reduce your heating bill
really quite significantly. If you are spending £800/yr on heating-
alone now, it is quite conceivable you could reduce that to £300 as
well as feeling somewhat warmer. Payback period would be quite long
even though.

You can insulate on the outside, but unless that is rendered it can
significantly change the character and may be prohibited if a Gr-II
listed building etc. If possible, however, you can the thermal mass of
the inside as long as you can stuff enough heat into it in the first
place. You would use polystyrene stuck to the wall with plastic pegs,
with an expanding mesh, and a render coat over the top - or something
along those lines.

On Oct 5, 9:19*pm, S R wrote:
My house is a semi built in 1873, from Yorkshire stone.

It is a devil of a job heating it and keeping the heat in.

I'm getting the existing poor quality double glazing replaced next summer, but I
am also considering cavity wall insulation.

replacing dg is unlikely to yield any useful result unless its so
broken its howling.


I'm not sure how effective CWI is in house such as mine, and also the effect it
has on resisting or promoting damp penetration.

You need to find out what construction your walls are. Dont assume
theyre all the same, old houses can have several different wall types.
Measure the wall thickness, and drill a little test hole to see if
there's a cavity in there, and if so of what depth. Also let us know
fi the stone's rough rubble or sawn blocks.

If there's no cavity there are other options.


NT

On 6 Oct, 18:08, Jim K wrote:
On 6 Oct, 00:10, "js.b1" wrote:

You can insulate on the outside, but unless that is rendered it can
significantly change the character and may be prohibited if a Gr-II
listed building etc. If possible, however, you can the thermal mass of
the inside as long as you can stuff enough heat into it in the first
place. You would use polystyrene stuck to the wall with plastic pegs,
with an expanding mesh, and a render coat over the top - or something
along those lines.

do you have a link to anywhere that has been done and works?

IMHO talking of "thermal mass" in these situations is somewhat of a
red herring as these thick walls are not isolated/insulated from the
earth they are built on....

Jim K

I have done it to my house. (DIY project.)