"Mike" wrote in message
...
"brugnospamsia" wrote

Dear group,

My home improvement programme is in danger of being held up due to
conflicting advice I have received regarding how to attach
insulated plaster
boards to 9 inch solid brick walls built with lime mortar.

Brent borough council insist on battening and hence a generous air
gap over
brickwork with no waterproofing treatment applied directly to the
wall :-


http://www.brent.gov.uk/bccs.nsf/248...944/bda0a799ca
60698c80256c1d0047621d/$FILE/BCCS%20Dry%20lining%20Solid%20Blockwork%20info%
20sheet%20No.7.doc

A video made 10 years ago by a local university shows waterproof
sand/cement
render being applied then the insulating boards attached with
adhesive dabs,
the boards then being skimmed.

The outside of the wall is rendered and I don't appear to have
problems with
penetrating damp


If your wall had been unrendered life would be much easier. You could
simply use a vapour barrier, PB and rockwool.

Unfortunately unDPCed solid walls should not be rendered on both
sides, nor vapour barriered on both sides, since damp will slowly
accumulate in the wall, and have nowhere to go. Injection DPCs do not
solve the problem.

Since youre already cement rendered on one side, you dont want to be
attaching any form of vapour barrier to he inside.

Yet if you use PB and glass wool, a vapour barrier you would need.


The possible solutions?

A. Remove external render, with real care to avoid damage, then
proceed with vapour barrier internally. Dont cement render these old
buildings, it can damage them.

B. Apply expanded clay in lime plaster to the interior. This gives
insulation with no vapour barrier, retaining wall breathability, and
without the damage cement sometimes causes.

C. Do nothing.


Your idea of venting to the loft might work, I dont know. It would
make damp worse in winter, but then dry it in summer. But if you do
that you will lose out on insulation value, and I didnt see where in
your sketch the rockwool is going.

In principle I imagine you could install PB with vapour barrier and
pipe the trapped air to a micropower drying unit, never heard it
tried.


Knowledge on old houses has come on a lot in the last ten years.
Look at www.periodproperty.co.uk for a variety of articles on the subject.

hear hear


NT

The message
from (N. Thornton) contains these words:

B. Apply expanded clay in lime plaster to the interior. This gives
insulation with no vapour barrier, retaining wall breathability, and
without the damage cement sometimes causes.

Not a solution I have previously heard of. How effective is that plaster
mix as insulation?

I am in a similar position to the op other than I have 2' thick rubble
filled stone walls and no external render.

--
Roger

"Roger" wrote in message
k...
The message
from (N. Thornton) contains these words:

B. Apply expanded clay in lime plaster to the interior. This gives
insulation with no vapour barrier, retaining wall breathability, and
without the damage cement sometimes causes.

Not a solution I have previously heard of. How effective is that plaster
mix as insulation?

I use it for floors as it needs to be a lot thicker than Kingspan/Celotex or
even Rockwool. LECA (Optiroc) in a lime/sand mix to a foot or so depth
definitely does lower heat loss through the floor though. A friend did put
a thin layer of it as an outside render but this was on a 'best attempt'
basis rather than trying to meet part L.



I am in a similar position to the op other than I have 2' thick rubble
filled stone walls and no external render.

Same here.

The message
from "Mike" contains these words:

B. Apply expanded clay in lime plaster to the interior. This gives
insulation with no vapour barrier, retaining wall breathability, and
without the damage cement sometimes causes.

Not a solution I have previously heard of. How effective is that plaster
mix as insulation?

I use it for floors as it needs to be a lot thicker than Kingspan/Celotex or
even Rockwool. LECA (Optiroc) in a lime/sand mix to a foot or so depth
definitely does lower heat loss through the floor though. A friend did put
a thin layer of it as an outside render but this was on a 'best attempt'
basis rather than trying to meet part L.

I had a google but couldn't find any reference to its use as wall
insulation. One of my round tuits near the top of the pile is to dig up
and re lay my solid ground floor but I think I will avoid the expanded
clay route as I would probably have to dig out to below my shallow
foundations. I can't afford to raise the floor level at all as headroom
is aleady minimal.

I am in a similar position to the op other than I have 2' thick rubble
filled stone walls and no external render.

Same here.

I note you have gone the batten out route but I have small rooms and
particularly in the kitchen, smallest bedroom and bathroom no space for
more than the thinest of insulation. One of my earlier jobs (still not
plastered out because of the insulation dilemma) was to increase the
size of the bedroom at the expense of the bathroom so space is really
tight in there now.

--
Roger

"Roger" wrote in message
k...
The message
from "Mike" contains these words:

B. Apply expanded clay in lime plaster to the interior. This gives
insulation with no vapour barrier, retaining wall breathability, and
without the damage cement sometimes causes.

Not a solution I have previously heard of. How effective is that
plaster
mix as insulation?

I use it for floors as it needs to be a lot thicker than
Kingspan/Celotex or
even Rockwool. LECA (Optiroc) in a lime/sand mix to a foot or so depth
definitely does lower heat loss through the floor though. A friend did
put
a thin layer of it as an outside render but this was on a 'best attempt'
basis rather than trying to meet part L.

I had a google but couldn't find any reference to its use as wall
insulation.

www.periodproperty.co.uk appear to have cleared their back files but google
has some cached. Start with

http://www.google.co.uk/search?q=cac...property.co.uk
/cgi-bin/discuss/forum.pl%3Fread%3D3966+LECA+render+site:www.periodproperty.
co.uk&hl=en%20target=nw

and work from there. But you will have to search the google cache, not the
web site itself.


One of my round tuits near the top of the pile is to dig up
and re lay my solid ground floor but I think I will avoid the expanded
clay route as I would probably have to dig out to below my shallow
foundations. I can't afford to raise the floor level at all as headroom
is aleady minimal.

Same here. Remember there is still a lot of sand and lime in the mix so use
very little clay in the mix near the wall (or none even - just leave it as
is) but a lot in the centre of the room. A couple of feet of this stuff is
definitely noticeable.


I am in a similar position to the op other than I have 2' thick rubble
filled stone walls and no external render.

Same here.

I note you have gone the batten out route but I have small rooms and
particularly in the kitchen, smallest bedroom and bathroom no space for
more than the thinest of insulation. One of my earlier jobs (still not
plastered out because of the insulation dilemma) was to increase the
size of the bedroom at the expense of the bathroom so space is really
tight in there now.

Fully understand. Ours is a very long 16'8" wide farmhouse internally with
2' walls each side so we decided to sacrifice the 8" for insulation, 4" on
each side - 35mm typical ventilated space, 50mm insulation and 12mm
plasterboard+skim. The alternative was heating bills of over £5k per annum
so it wasn't too hard to sacrifice the space. In your case I would
superinsulate the loft and the floor, plus work on draughts and suchlike.
Are you allowed to double glaze ? (but not with PVC please :-)

The message
from "Mike" contains these words:

{ Apply expanded clay in lime plaster }

I had a google but couldn't find any reference to its use as wall
insulation.

www.periodproperty.co.uk appear to have cleared their back files but google
has some cached. Start with

http://www.google.co.uk/search?q=cac...property.co.uk
/cgi-bin/discuss/forum.pl%3Fread%3D3966+LECA+render+site:www.periodproperty.
co.uk&hl=en%20target=nw

and work from there. But you will have to search the google cache, not the
web site itself.

Thanks. I will try that tomorrow. I wasn't previously aware google had a
cache.

One of my round tuits near the top of the pile is to dig up
and re lay my solid ground floor but I think I will avoid the expanded
clay route as I would probably have to dig out to below my shallow
foundations. I can't afford to raise the floor level at all as headroom
is already minimal.

Same here. Remember there is still a lot of sand and lime in the mix so use
very little clay in the mix near the wall (or none even - just leave it as
is) but a lot in the centre of the room. A couple of feet of this stuff is
definitely noticeable.

2 feet would definitely get below what little foundations I have. ISTR
that most heat through the floor leaves close to the walls so insulation
is more important there. Someone in the past replaced most of my
(presumably stone flagged) floor with poor quality concrete with a
dubious dpm. I am inclined to just go the modern route for the
replacement.

I am in a similar position to the op other than I have 2' thick rubble
filled stone walls and no external render.

Same here.

I note you have gone the batten out route but I have small rooms and
particularly in the kitchen, smallest bedroom and bathroom no space for
more than the thinnest of insulation. One of my earlier jobs (still not
plastered out because of the insulation dilemma) was to increase the
size of the bedroom at the expense of the bathroom so space is really
tight in there now.

Fully understand. Ours is a very long 16'8" wide farmhouse internally with
2' walls each side so we decided to sacrifice the 8" for insulation, 4" on
each side - 35mm typical ventilated space, 50mm insulation and 12mm
plasterboard+skim. The alternative was heating bills of over £5k per annum
so it wasn't too hard to sacrifice the space. In your case I would
superinsulate the loft and the floor, plus work on draughts and suchlike.
Are you allowed to double glaze ? (but not with PVC please :-)

Double glazing is one of the few jobs I have got a builder in for so
far. Double glazed with hardwood frames to replace the rotting single
glazed softwood. Some of the window openings showed evidence of long
departed stone mullions but I decided not to attempt to reinstate those,
the windows are very small by modern standards already. I didn't enquire
about the type of glass. :-)

As to loft, only in one small section do I have a loft, the remainder of
the upstairs is open to the pitch of the roof. Luckily this place is not
listed. Nothing worth listing in the first place I suspect, it is only a
humble cottage attached to a larger field barn. My heating bills aren't
too bad but I could do with something on the walls that makes a
significant difference without eating space. I can't afford more than 2"
on most of the external walls and in some places more than an inch would
be an embarrassment.

--
Roger

"N. Thornton" wrote in message
om...
"Mike" wrote in message
...
"brugnospamsia" wrote

Dear group,

My home improvement programme is in danger of being held up due to
conflicting advice I have received regarding how to attach
insulated plaster
boards to 9 inch solid brick walls built with lime mortar.

Brent borough council insist on battening and hence a generous air
gap over
brickwork with no waterproofing treatment applied directly to the
wall :-



http://www.brent.gov.uk/bccs.nsf/248...944/bda0a799ca

60698c80256c1d0047621d/$FILE/BCCS%20Dry%20lining%20Solid%20Blockwork%20info%
20sheet%20No.7.doc

A video made 10 years ago by a local university shows waterproof
sand/cement
render being applied then the insulating boards attached with
adhesive dabs,
the boards then being skimmed.

The outside of the wall is rendered and I don't appear to have
problems with
penetrating damp


If your wall had been unrendered life would be much easier. You could
simply use a vapour barrier, PB and rockwool.

Unfortunately unDPCed solid walls should not be rendered on both
sides, nor vapour barriered on both sides, since damp will slowly
accumulate in the wall, and have nowhere to go. Injection DPCs do not
solve the problem.

Since youre already cement rendered on one side, you dont want to be
attaching any form of vapour barrier to he inside.

Yet if you use PB and glass wool, a vapour barrier you would need.


I was planning to use foam-backed plasterboard, though perhaps I would be
better using thicker battens and seperate insulation
(spaced from wall with netting ?) and foil-backed plasterboard - thus making
the decorative layer "serviceable" ?
would I be better off using soft insulation ?

I've just amended my diagram :-
http://uk.geocities.com/gentlegreengiant/walldetail.JPG

----------------------------



The possible solutions?

A. Remove external render, with real care to avoid damage, then
proceed with vapour barrier internally. Dont cement render these old
buildings, it can damage them.

B. Apply expanded clay in lime plaster to the interior. This gives
insulation with no vapour barrier, retaining wall breathability, and
without the damage cement sometimes causes.

C. Do nothing.


Your idea of venting to the loft might work, I dont know. It would
make damp worse in winter, but then dry it in summer. But if you do
that you will lose out on insulation value, and I didnt see where in
your sketch the rockwool is going.

In principle I imagine you could install PB with vapour barrier and
pipe the trapped air to a micropower drying unit, never heard it
tried.


Knowledge on old houses has come on a lot in the last ten years.
Look at www.periodproperty.co.uk for a variety of articles on the
subject.

hear hear


NT

"brugnospamsia" wrote in message
k...

"N. Thornton" wrote in message
om...
"Mike" wrote in message
...
"brugnospamsia" wrote

Dear group,

My home improvement programme is in danger of being held up due to
conflicting advice I have received regarding how to attach
insulated plaster
boards to 9 inch solid brick walls built with lime mortar.

Brent borough council insist on battening and hence a generous air
gap over
brickwork with no waterproofing treatment applied directly to the
wall :-




http://www.brent.gov.uk/bccs.nsf/248...944/bda0a799ca


60698c80256c1d0047621d/$FILE/BCCS%20Dry%20lining%20Solid%20Blockwork%20info%
20sheet%20No.7.doc

A video made 10 years ago by a local university shows waterproof
sand/cement
render being applied then the insulating boards attached with
adhesive dabs,
the boards then being skimmed.

The outside of the wall is rendered and I don't appear to have
problems with
penetrating damp


If your wall had been unrendered life would be much easier. You could
simply use a vapour barrier, PB and rockwool.

Unfortunately unDPCed solid walls should not be rendered on both
sides, nor vapour barriered on both sides, since damp will slowly
accumulate in the wall, and have nowhere to go. Injection DPCs do not
solve the problem.

Since youre already cement rendered on one side, you dont want to be
attaching any form of vapour barrier to he inside.

Yet if you use PB and glass wool, a vapour barrier you would need.


I was planning to use foam-backed plasterboard, though perhaps I would be
better using thicker battens and seperate insulation
(spaced from wall with netting ?) and foil-backed plasterboard - thus
making
the decorative layer "serviceable" ?
would I be better off using soft insulation ?

I've just amended my diagram :-
http://uk.geocities.com/gentlegreengiant/walldetail.JPG

----------------------------

I just realised I need to treat the upstairs and downstairs as one system


http://uk.geocities.com/gentlegreengiant/wallsystem.jpg

not yet sure how I will achieve it .......

I'm beginning to wish I never started this !





The possible solutions?

A. Remove external render, with real care to avoid damage, then
proceed with vapour barrier internally. Dont cement render these old
buildings, it can damage them.

B. Apply expanded clay in lime plaster to the interior. This gives
insulation with no vapour barrier, retaining wall breathability, and
without the damage cement sometimes causes.

C. Do nothing.


Your idea of venting to the loft might work, I dont know. It would
make damp worse in winter, but then dry it in summer. But if you do
that you will lose out on insulation value, and I didnt see where in
your sketch the rockwool is going.

In principle I imagine you could install PB with vapour barrier and
pipe the trapped air to a micropower drying unit, never heard it
tried.


Knowledge on old houses has come on a lot in the last ten years.
Look at www.periodproperty.co.uk for a variety of articles on the
subject.

hear hear


NT

"brugnospamsia" wrote in message
...
----------------------------

I just realised I need to treat the upstairs and downstairs as one system



http://uk.geocities.com/gentlegreengiant/wallsystem.jpg

Ah - now I've seen what you've got it's a lot clearer. But you'll never get
air to move effectively all the way from the underfloor to the roof. I
would separate these out. Most damp is downstairs and needs more effective
dealing with by inserting air bricks in the wall.

I found it easiest to mount the batterning to the ceiling and floor. The
only point it touches the wall is a couple of spacers into the wooden
lintels above the windows for some extra stability.

The seals you show would be top and bottom I assume. Using glued on coving
and skirting is one option.

Don't you have eaves in the roof ? If so the air should turn right and feed
out there. If not you've got a problem as the damp will accumulate there.






I'm beginning to wish I never started this !

Yep - know exactly how you feel. But our old farmhouse now takes about a
quarter of the heat it took to heat before I started and the damp feel to
the air has gone.

"Mike" wrote in message
...

"brugnospamsia" wrote in message
...
----------------------------

I just realised I need to treat the upstairs and downstairs as one system



http://uk.geocities.com/gentlegreengiant/wallsystem.jpg

Ah - now I've seen what you've got it's a lot clearer. But you'll never
get
air to move effectively all the way from the underfloor to the roof. I
would separate these out. Most damp is downstairs and needs more
effective
dealing with by inserting air bricks in the wall.

I found it easiest to mount the batterning to the ceiling and floor. The
only point it touches the wall is a couple of spacers into the wooden
lintels above the windows for some extra stability.

The seals you show would be top and bottom I assume. Using glued on
coving
and skirting is one option.


Don't you have eaves in the roof ? If so the air should turn right and
feed
out there. If not you've got a problem as the damp will accumulate there.

unfortunately not - it's a centre-valley :

http://uk.geocities.com/gentlegreengiant/ruinbig.jpg








I'm beginning to wish I never started this !

Yep - know exactly how you feel. But our old farmhouse now takes about a
quarter of the heat it took to heat before I started and the damp feel to
the air has gone.

"brugnospamsia" wrote in message
k...

http://uk.geocities.com/gentlegreengiant/wallsystem.jpg


Don't you have eaves in the roof ? If so the air should turn right and
feed
out there. If not you've got a problem as the damp will accumulate
there.

unfortunately not - it's a centre-valley :

http://uk.geocities.com/gentlegreengiant/ruinbig.jpg


Perhaps an airbrick or two at the top of the upstairs level as well might be
a good ideal if it is possible. Would help vent the roof better as well as
the area behind the insulation.

Remember cold is bad but damp is always far far worse, hot or cold !!

"brugnospamsia" wrote in message
k...


I was planning to use foam-backed plasterboard, though perhaps I would be
better using thicker battens and seperate insulation

Yes. The insulation is a lot cheaper that way as well.