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Default Cavity wall insulation

I thought that all modern houses had to have cavity wall insulation.

However my neighbour has found that their 8 year old house does not
have cavity wall insulation. Apparently the builders (Redrow) were
able to get away with using just thermalite blocks and no cavity wall
insulation.

We are now planning to have the insulation installed, but what were
the regs 8 years ago and should Redrow have been allowed to get away
with not installing cavity wall insulation?

Incidently we thought the house was a bit cold and the heating bills
high.
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chudford wrote:
I thought that all modern houses had to have cavity wall insulation.

However my neighbour has found that their 8 year old house does not
have cavity wall insulation. Apparently the builders (Redrow) were
able to get away with using just thermalite blocks and no cavity wall
insulation.

We are now planning to have the insulation installed, but what were
the regs 8 years ago and should Redrow have been allowed to get away
with not installing cavity wall insulation?

Incidently we thought the house was a bit cold and the heating bills
high.


There has never been a requirement to install CWI on any building - the only
requirement is that the wall must meet certain levels of heat retention,
this can be acheived by using thicker thermalite blocks and having them dry
lined.

I'll wager that the walls in your house are about 350mm wide - 100mm outside
brick, 75mm cavity and 150mm inside block...the reamaining 25mm will be
drylining.

Why housebuilders go down this route is beyond me - the cost of the thicker
blocks far outweighs the price of having regular blocks and CWI


--
Phil L
RSRL Tipster Of The Year 2008


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Default Cavity wall insulation

chudford wrote:
I thought that all modern houses had to have cavity wall insulation.

However my neighbour has found that their 8 year old house does not
have cavity wall insulation. Apparently the builders (Redrow) were
able to get away with using just thermalite blocks and no cavity wall
insulation.

We are now planning to have the insulation installed, but what were
the regs 8 years ago and should Redrow have been allowed to get away
with not installing cavity wall insulation?

Incidently we thought the house was a bit cold and the heating bills
high.


Looking on the good side, you can now upgrade the insulation further with
CWI, where as, if they had just put this in, and not used the thicker
thermalite blocks, then upgrading the insulation would have been more
expensive and more disruptive, so really they have done you a favor :-)

Toby...

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Default Cavity wall insulation

chudford wrote:
I thought that all modern houses had to have cavity wall insulation.

However my neighbour has found that their 8 year old house does not
have cavity wall insulation. Apparently the builders (Redrow) were
able to get away with using just thermalite blocks and no cavity wall
insulation.

We are now planning to have the insulation installed, but what were
the regs 8 years ago and should Redrow have been allowed to get away
with not installing cavity wall insulation?

Incidently we thought the house was a bit cold and the heating bills
high.

I have a 10 yr old Rerow home , again without cavity wall insulation.
The construction is, as you say, themalite block but also with dry
lining. This was apparently good enough for the regs at the time. As
an aside, if you hve small bore heating, the pipes come down the wall
between the plasterboard and the blocks, sometimes in the corner of the
room.

Malcolm
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On Sun, 16 Nov 2008 19:20:28 GMT Phil L wrote :
Why housebuilders go down this route is beyond me - the cost of the thicker
blocks far outweighs the price of having regular blocks and CWI


IIRC the NHBC do not allow CWI in some exposed areas

--
Tony Bryer, 'Software to build on' from Greentram
www.superbeam.co.uk www.superbeam.com www.greentram.com



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Default Cavity wall insulation


"Malcolm" wrote in message
news
chudford wrote:
I thought that all modern houses had to have cavity wall insulation.

However my neighbour has found that their 8 year old house does not
have cavity wall insulation. Apparently the builders (Redrow) were
able to get away with using just thermalite blocks and no cavity wall
insulation.

We are now planning to have the insulation installed, but what were
the regs 8 years ago and should Redrow have been allowed to get away
with not installing cavity wall insulation?

Incidently we thought the house was a bit cold and the heating bills
high.

I have a 10 yr old Rerow home , again without cavity wall insulation. The
construction is, as you say, themalite block but also with dry lining.
This was apparently good enough for the regs at the time. As an aside, if
you hve small bore heating, the pipes come down the wall between the
plasterboard and the blocks, sometimes in the corner of the room.

Malcolm


How can you tell if a house has CWI? I have a 2001 build (Permisson, I
think) house. How would one tell if it has CWI?


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Slider wrote:

How can you tell if a house has CWI? I have a 2001 build (Permisson,
I think) house. How would one tell if it has CWI?


drill a hole in the cement joint and have a poke around.
The hole only needs to be about 5mm diameter, but obviously 100mm deep, and
poke in a piece of wire, a straightened coathanger preferably, and if
there's any sponginess, it's insulated with yellow fibreglass batts, if
there isn't, it may still be insulated with loose fill fibreglass, and to
check for this, add a bit of gob oil to the end of the wire and have another
poke, fibreglass will be white, rockwool will be cement coloured.
If it's insulated with polystyrene or celotex type rigid foam, you should be
able to push the wire into it and you can 'feel' the sqeakiness of it as the
wire goes through, if that makes sense.

I'll wager a pound to a piece of dogturd that it's done with white blowing
wool - I used to do Persimmon homes every Saturday morning for years, and we
used white fibre,.

--
Phil L
RSRL Tipster Of The Year 2008


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"Phil L" wrote in message
om...
Slider wrote:

How can you tell if a house has CWI? I have a 2001 build (Permisson,
I think) house. How would one tell if it has CWI?


drill a hole in the cement joint and have a poke around.
The hole only needs to be about 5mm diameter, but obviously 100mm deep,
and poke in a piece of wire, a straightened coathanger preferably, and if
there's any sponginess, it's insulated with yellow fibreglass batts, if
there isn't, it may still be insulated with loose fill fibreglass, and to
check for this, add a bit of gob oil to the end of the wire and have
another poke, fibreglass will be white, rockwool will be cement coloured.
If it's insulated with polystyrene or celotex type rigid foam, you should
be able to push the wire into it and you can 'feel' the sqeakiness of it
as the wire goes through, if that makes sense.

I'll wager a pound to a piece of dogturd that it's done with white blowing
wool - I used to do Persimmon homes every Saturday morning for years, and
we used white fibre,.

--
Phil L
RSRL Tipster Of The Year 2008


Thanks for the reply. Actually I was wrong with Persimmon, it was built by
Alfted McAlpine. Have you any experience of these?


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Slider wrote:


Thanks for the reply. Actually I was wrong with Persimmon, it was
built by Alfted McAlpine. Have you any experience of these?


No.
McAlpine, and Barratt come to think of it, were never on our list of new
build sites.
This doesn't mean it isn't insulated though.


--
Phil L
RSRL Tipster Of The Year 2008


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On 16 Nov, 17:46, chudford wrote:
I thought that all modern houses had to have cavity wall insulation.


No: Walls have to meet the thermal resistance standard specified in
the building regs.
There are many ways to achieve that.


snip

We are now planning to have the insulation installed,

I'd be very wary of doing that. It may last a few years but you might
end up with a different problem or 2. Cavity walls need an air gap in
the cavity of at least 25mm against the outside wall. Water vapour
from the atmosphere inevitably percolates through the outside brick
skin & the air gap allows this to run down the inner surface of the
wall. Without it the insulating rockwool or fibre in the cavity will
get wet & become ineffective. Other types of filling have their own
problems. Also shaling may occur on the outside brick face.

but what were
the regs 8 years ago


Much the same as now except required level of thermal resistance has
been upped + some options verboten. You need to check the building
regs for exact info or if you are lucky someone else will be along
this way soon with chapter & verse :-)

and should Redrow have been allowed to get away
with not installing cavity wall insulation?


IMHO they didn't 'get away' with anything: they made the best
engineering decision.


Incidently we thought the house was a bit cold and the heating bills
high.


underrated CH boiler? under-rated rads not heating up fast enough?

You might do better to concentrate your efforts on upping attic
insulation & look at ways of minimising heat loss in exposed sections
of your house - curtains, carpets etc can all help. Can you mask a
wall exposed to the full force of cold winds so that they are
deflected, eg by repositioning a shed? Consider putting rockwool
insulation between ceiling joists over living rooms. We found that
made quite a difference to comfort in our sitting room.

HTH


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replying to chudford, Steve Scott wrote:
Hi I'm in a persimmon Hatfield house. The house is 18 months old. When sold I
asked the cwi question and was told they are a traditional builder and as such
didn't supply any form of cwi just brick and a thermal block. So what I'm
saying is some builders only do the bare minimum.

--
for full context, visit https://www.homeownershub.com/uk-diy...on-520978-.htm


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On Tuesday, 18 November 2008 23:56:49 UTC, jim wrote:
On 16 Nov, 17:46, chudford wrote:
I thought that all modern houses had to have cavity wall insulation.


No: Walls have to meet the thermal resistance standard specified in
the building regs.
There are many ways to achieve that.


snip

We are now planning to have the insulation installed,

I'd be very wary of doing that. It may last a few years but you might
end up with a different problem or 2. Cavity walls need an air gap in
the cavity of at least 25mm against the outside wall. Water vapour
from the atmosphere inevitably percolates through the outside brick
skin & the air gap allows this to run down the inner surface of the
wall. Without it the insulating rockwool or fibre in the cavity will
get wet & become ineffective. Other types of filling have their own
problems. Also shaling may occur on the outside brick face.

but what were
the regs 8 years ago


Much the same as now except required level of thermal resistance has
been upped + some options verboten. You need to check the building
regs for exact info or if you are lucky someone else will be along
this way soon with chapter & verse :-)

and should Redrow have been allowed to get away
with not installing cavity wall insulation?


IMHO they didn't 'get away' with anything: they made the best
engineering decision.


Incidently we thought the house was a bit cold and the heating bills
high.


underrated CH boiler? under-rated rads not heating up fast enough?

You might do better to concentrate your efforts on upping attic
insulation & look at ways of minimising heat loss in exposed sections
of your house - curtains, carpets etc can all help. Can you mask a
wall exposed to the full force of cold winds so that they are
deflected, eg by repositioning a shed? Consider putting rockwool
insulation between ceiling joists over living rooms. We found that
made quite a difference to comfort in our sitting room.



Blown in cavity wall fibres are silicon coated to make them water repellent.
As are the cavity wall bats.
https://www.nia-uk.org/consumer/unde...-mineral-wool/
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2008?
Deja view all over again.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"harry" wrote in message
...
On Tuesday, 18 November 2008 23:56:49 UTC, jim wrote:
On 16 Nov, 17:46, chudford wrote:
I thought that all modern houses had to have cavity wall insulation.


No: Walls have to meet the thermal resistance standard specified in
the building regs.
There are many ways to achieve that.


snip

We are now planning to have the insulation installed,

I'd be very wary of doing that. It may last a few years but you might
end up with a different problem or 2. Cavity walls need an air gap in
the cavity of at least 25mm against the outside wall. Water vapour
from the atmosphere inevitably percolates through the outside brick
skin & the air gap allows this to run down the inner surface of the
wall. Without it the insulating rockwool or fibre in the cavity will
get wet & become ineffective. Other types of filling have their own
problems. Also shaling may occur on the outside brick face.

but what were
the regs 8 years ago


Much the same as now except required level of thermal resistance has
been upped + some options verboten. You need to check the building
regs for exact info or if you are lucky someone else will be along
this way soon with chapter & verse :-)

and should Redrow have been allowed to get away
with not installing cavity wall insulation?


IMHO they didn't 'get away' with anything: they made the best
engineering decision.


Incidently we thought the house was a bit cold and the heating bills
high.


underrated CH boiler? under-rated rads not heating up fast enough?

You might do better to concentrate your efforts on upping attic
insulation & look at ways of minimising heat loss in exposed sections
of your house - curtains, carpets etc can all help. Can you mask a
wall exposed to the full force of cold winds so that they are
deflected, eg by repositioning a shed? Consider putting rockwool
insulation between ceiling joists over living rooms. We found that
made quite a difference to comfort in our sitting room.



Blown in cavity wall fibres are silicon coated to make them water
repellent.
As are the cavity wall bats.
https://www.nia-uk.org/consumer/unde...-mineral-wool/


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On Sunday, November 16, 2008 at 7:20:28 PM UTC, Phil L wrote:
chudford wrote:



Why housebuilders go down this route is beyond me - the cost of the thicker
blocks far outweighs the price of having regular blocks and CWI


Perhaps it's quicker to build. The cost of the materials might not be a major factor.

Robert




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wrote
Phil L wrote
chudford wrote


Why housebuilders go down this route is beyond me - the cost of the
thicker blocks far outweighs the price of having regular blocks and CWI


Perhaps it's quicker to build. The cost of the materials might not be a
major factor.


The thicker blocks and be a real bugger at the end
of the day, lifting them up to head height etc.



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On 14/06/2018 06:12, harry wrote:
On Tuesday, 18 November 2008 23:56:49 UTC, jim wrote:
On 16 Nov, 17:46, chudford wrote:
I thought that all modern houses had to have cavity wall insulation.


You might do better to concentrate your efforts on upping attic
insulation & look at ways of minimising heat loss in exposed sections
of your house - curtains, carpets etc can all help. Can you mask a
wall exposed to the full force of cold winds so that they are
deflected, eg by repositioning a shed? Consider putting rockwool
insulation between ceiling joists over living rooms. We found that
made quite a difference to comfort in our sitting room.


Blown in cavity wall fibres are silicon coated to make them water repellent.
As are the cavity wall bats.
https://www.nia-uk.org/consumer/unde...-mineral-wool/


That wasn't always so. Newcastle has a problem with rogue cavity wall
installations from about 10 years ago that are still just about under
guarantee failing in large numbers because the fibre method used has
bridged the outer and inner wall causing widespread penetrating damp.

I happened to meet one of the insurance assessors when he was looking at
my brother in law's house. It has wrong method of insulation but so far
doesn't have any obvious signs of water ingress. The guy suggested
moving any furniture backed up against outside walls and taking a look
since the deadline for making a claim was fast approaching.
--
Regards,
Martin Brown
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On Thu, 14 Jun 2018 16:36:13 +1000, cantankerous geezer Rot Speed blabbered,
again:

Perhaps it's quicker to build. The cost of the materials might not be a
major factor.


The thicker blocks and be a real bugger


Thick and a bugger, that's what you are, Rot!

--
Sqwertz to Rot Speed:
"This is just a hunch, but I'm betting you're kinda an argumentative
asshole.
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