On Fri, 23 Jan 2004 10:09:27 -0000, "IMM" wrote:


"David Moodie" wrote in message
...

"Dean Richard Benson" wrote in
message newsan.2004.01.22.17.24.49.501186@spamlessharker hill.co.uk...
On Thu, 22 Jan 2004 15:28:12 +0000, Andy Hall wrote:
That's exactly what I'm saying. Insulate it to the level of the walls
which is a U value of 0.25 to 0.35 for a place with cavity walls and
insulation. That equates to 100-150mm of glass fibre, not
350mm-600mm.

I think I am seeing your point.

On an older property, the U value of the walls can easily be 2.0.

Yep, my house is 250 years old, so really thick walls, but certainly no
cavity.

There is very little point in reducing the U value for the roof below
0.25 in the context of that.

Is there a way to find out the current heat loss through a wall?

Thanks

Dean

I was going to suggest the Knauf U value calculator normally available as
a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the moment as
it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you \re still
interpreted.


The point is that the house has to be viewed as upper and lower floors. the
difference in the upper floors is marked in most houses.


Heatloss through walls of the same construction, accounting for
temperature variation, varies depending on whether you are upstairs or
downstairs?


---

..andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 09:59:12 -0000, "David Moodie"
wrote:


"Dean Richard Benson" wrote in
message newsan.2004.01.22.17.24.49.501186@spamlessharker hill.co.uk...
On Thu, 22 Jan 2004 15:28:12 +0000, Andy Hall wrote:
That's exactly what I'm saying. Insulate it to the level of the walls
which is a U value of 0.25 to 0.35 for a place with cavity walls and
insulation. That equates to 100-150mm of glass fibre, not
350mm-600mm.

I think I am seeing your point.

On an older property, the U value of the walls can easily be 2.0.

Yep, my house is 250 years old, so really thick walls, but certainly no
cavity.

There is very little point in reducing the U value for the roof below
0.25 in the context of that.

Is there a way to find out the current heat loss through a wall?

Thanks

Dean

I was going to suggest the Knauf U value calculator normally available as a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the moment as it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you \re still
interpreted.

cheers

David


THe heatloss calculator programs from the radiator manufacturers have
this data as well....


..andy

To email, substitute .nospam with .gl

"IMM" wrote in message
...

"Andy Hall" wrote in message
...

It does!!!!!!!!!! The upstairs then is much more well insulated,
warmer
and
consumes less fuel to heat. The upstairs rooms benefit greatly by
heavy
insulation in the loft.

Do I need to do the sums again for
you to demonstrate the point?

Well do them by having a before and after of the ground floor and the
1st
floor.

Here's my house as an exercise:-

Foot print ~ 70m2
Downstairs wall height ~ 2.1m
Upstairs wall height ~ 2.2m
Wall construction:-
downstairs 27 m solid wall construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
upstairs 27 m tile hung lath/plaster construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
Ground floor :- thick concrete + screed + covering U-val ~ 0.3
Ceiling Floorbaord/Joist/Plaster U-val ~ 1.6
Loft currently insulated with ~ 100mm mineral wool U-val ~ 0.5

Windows:-
Downstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8
Upstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8

Doors:-
6 m2 mixed construction U-val ~ 3.0

Air changes :- 1.5 per hour

Design parameters
=================
Outside temp -3 C

Downstairs temp 21 C (delta-T = 24)
Upstairs temp 18 C (delta-T = 21)

Heat loss - downstairs
======================
Floor = 70 x 0.3 x 24 = 504 W
Walls = (27*2.1 - 5.9 - 3) * 2.0 * 24 ~ 2295 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 2462 W

Windows = 2.2 * 4.8 * 24 = 254 W
+5.9 * 3.8 * 24 = 538 W
Windows Total = 792 W

Doors = 6 * 3 * 24 = 432 W
Ceiling = 70 * 1.6 * 3 = 336 W
Air changes = 70 * 2.1 * 0.36 * 1.5 * 24 = 1896 W

Downstairs losses = 6422 W

Heat loss - upstairs
====================
Floor = 70 x 1.6 x -3 = 336 W
Walls = (27*2.2 - 5.9) * 2.0 * 21 ~ 2247 W
+( 8*2.2 - 2.2) * 0.6 * 21 = 194 W
Walls Total = 2441 W

Windows = 2.2 * 4.8 * 21 = 222 W
+5.9 * 3.8 * 21 = 471 W
Windows Total = 693 W

Ceiling = 70 * 0.5 * 21 = 735 W
Air changes = 70 * 2.2 * 0.36 * 1.5 * 21 = 1746 W

Upstairs losses = 5951 W

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%


Then see how much fuel is saved in each. I bet the 1st floor saves
more fuel. Then there is superior cooling of the 1st floor and higher
comfort conditions.

"Andy Hall" wrote in message

I was going to suggest the Knauf U value calculator normally available
as
a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the moment
as
it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you \re
still
interpreted.

The point is that the house has to be viewed
as upper and lower floors. the
difference in the upper floors is marked
in most houses.

Heatloss through walls of the same construction, accounting for
temperature variation, varies depending on whether you are upstairs or
downstairs?

Grow up! The rooms in the upper floors have a large area that is the
ceiling with a cold loft over in winter and hot loft over in summer.
Insulate the loft heavily and heat loss in these rooms reduces considerably,
giving superior comfort conditions in winter and summer, moreso than the
ground floors.

You didn't know that did you?



---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Andy Hall" wrote in message
...

It does!!!!!!!!!! The upstairs then is much more well insulated,
warmer
and
consumes less fuel to heat. The upstairs rooms benefit greatly by
heavy
insulation in the loft.

Do I need to do the sums again for
you to demonstrate the point?

Well do them by having a before and after of the ground floor and the
1st
floor.

Here's my house as an exercise:-

Foot print ~ 70m2
Downstairs wall height ~ 2.1m
Upstairs wall height ~ 2.2m
Wall construction:-
downstairs 27 m solid wall construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
upstairs 27 m tile hung lath/plaster construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
Ground floor :- thick concrete + screed + covering U-val ~ 0.3
Ceiling Floorbaord/Joist/Plaster U-val ~ 1.6
Loft currently insulated with ~ 100mm mineral wool U-val ~ 0.5

Windows:-
Downstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8
Upstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8

Doors:-
6 m2 mixed construction U-val ~ 3.0

Air changes :- 1.5 per hour

Design parameters
=================
Outside temp -3 C

Downstairs temp 21 C (delta-T = 24)
Upstairs temp 18 C (delta-T = 21)

Heat loss - downstairs
======================
Floor = 70 x 0.3 x 24 = 504 W
Walls = (27*2.1 - 5.9 - 3) * 2.0 * 24 ~ 2295 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 2462 W

Windows = 2.2 * 4.8 * 24 = 254 W
+5.9 * 3.8 * 24 = 538 W
Windows Total = 792 W

Doors = 6 * 3 * 24 = 432 W
Ceiling = 70 * 1.6 * 3 = 336 W
Air changes = 70 * 2.1 * 0.36 * 1.5 * 24 = 1896 W

Downstairs losses = 6422 W

Heat loss - upstairs
====================
Floor = 70 x 1.6 x -3 = 336 W
Walls = (27*2.2 - 5.9) * 2.0 * 21 ~ 2247 W
+( 8*2.2 - 2.2) * 0.6 * 21 = 194 W
Walls Total = 2441 W

Windows = 2.2 * 4.8 * 21 = 222 W
+5.9 * 3.8 * 21 = 471 W
Windows Total = 693 W

Ceiling = 70 * 0.5 * 21 = 735 W
Air changes = 70 * 2.2 * 0.36 * 1.5 * 21 = 1746 W

Upstairs losses = 5951 W

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again. Also what
about the hallway which is also upstairs and downstairs. Look specifically
at the upper rooms and see the difference. Also there is the matters of
keeping the upper rooms cool in summer too. 400mm does that wonderfully.
It is a win, win situation.


---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

On Fri, 23 Jan 2004 11:00:34 -0000, "Neil Jones"
wrote:



Here's my house as an exercise:-

Foot print ~ 70m2
Downstairs wall height ~ 2.1m
Upstairs wall height ~ 2.2m
Wall construction:-
downstairs 27 m solid wall construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
upstairs 27 m tile hung lath/plaster construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
Ground floor :- thick concrete + screed + covering U-val ~ 0.3
Ceiling Floorbaord/Joist/Plaster U-val ~ 1.6
Loft currently insulated with ~ 100mm mineral wool U-val ~ 0.5

Windows:-
Downstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8
Upstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8

Doors:-
6 m2 mixed construction U-val ~ 3.0

Air changes :- 1.5 per hour

Design parameters
=================
Outside temp -3 C

Downstairs temp 21 C (delta-T = 24)
Upstairs temp 18 C (delta-T = 21)

Heat loss - downstairs
======================
Floor = 70 x 0.3 x 24 = 504 W
Walls = (27*2.1 - 5.9 - 3) * 2.0 * 24 ~ 2295 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 2462 W

Windows = 2.2 * 4.8 * 24 = 254 W
+5.9 * 3.8 * 24 = 538 W
Windows Total = 792 W

Doors = 6 * 3 * 24 = 432 W
Ceiling = 70 * 1.6 * 3 = 336 W
Air changes = 70 * 2.1 * 0.36 * 1.5 * 24 = 1896 W

Downstairs losses = 6422 W

Heat loss - upstairs
====================
Floor = 70 x 1.6 x -3 = 336 W
Walls = (27*2.2 - 5.9) * 2.0 * 21 ~ 2247 W
+( 8*2.2 - 2.2) * 0.6 * 21 = 194 W
Walls Total = 2441 W

Windows = 2.2 * 4.8 * 21 = 222 W
+5.9 * 3.8 * 21 = 471 W
Windows Total = 693 W

Ceiling = 70 * 0.5 * 21 = 735 W
Air changes = 70 * 2.2 * 0.36 * 1.5 * 21 = 1746 W

Upstairs losses = 5951 W

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%



These are quite typical numbers, Neil.

I guess that this is an older house with a new extension?

It's interesting to note that the losses are close to being the same
upstairs and downstairs.



..andy

To email, substitute .nospam with .gl

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it cost to
buy 70 m2 loft insulation, at a depth of 300mm?

Also what
about the hallway which is also upstairs and downstairs.

What about it?

"Andy Hall" wrote in message
...

These are quite typical numbers, Neil.

I guess that this is an older house with a new extension?

Yes. The old part is 500 year old, or so. The extension was bulit in
1995.

It's interesting to note that the losses are close to being the same
upstairs and downstairs.

Quite.



.andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 11:15:14 -0000, "IMM" wrote:


"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Andy Hall" wrote in message
...

It does!!!!!!!!!! The upstairs then is much more well insulated,
warmer
and
consumes less fuel to heat. The upstairs rooms benefit greatly by
heavy
insulation in the loft.

Do I need to do the sums again for
you to demonstrate the point?

Well do them by having a before and after of the ground floor and the
1st
floor.

Here's my house as an exercise:-

Foot print ~ 70m2
Downstairs wall height ~ 2.1m
Upstairs wall height ~ 2.2m
Wall construction:-
downstairs 27 m solid wall construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
upstairs 27 m tile hung lath/plaster construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
Ground floor :- thick concrete + screed + covering U-val ~ 0.3
Ceiling Floorbaord/Joist/Plaster U-val ~ 1.6
Loft currently insulated with ~ 100mm mineral wool U-val ~ 0.5

Windows:-
Downstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8
Upstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8

Doors:-
6 m2 mixed construction U-val ~ 3.0

Air changes :- 1.5 per hour

Design parameters
=================
Outside temp -3 C

Downstairs temp 21 C (delta-T = 24)
Upstairs temp 18 C (delta-T = 21)

Heat loss - downstairs
======================
Floor = 70 x 0.3 x 24 = 504 W
Walls = (27*2.1 - 5.9 - 3) * 2.0 * 24 ~ 2295 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 2462 W

Windows = 2.2 * 4.8 * 24 = 254 W
+5.9 * 3.8 * 24 = 538 W
Windows Total = 792 W

Doors = 6 * 3 * 24 = 432 W
Ceiling = 70 * 1.6 * 3 = 336 W
Air changes = 70 * 2.1 * 0.36 * 1.5 * 24 = 1896 W

Downstairs losses = 6422 W

Heat loss - upstairs
====================
Floor = 70 x 1.6 x -3 = 336 W
Walls = (27*2.2 - 5.9) * 2.0 * 21 ~ 2247 W
+( 8*2.2 - 2.2) * 0.6 * 21 = 194 W
Walls Total = 2441 W

Windows = 2.2 * 4.8 * 21 = 222 W
+5.9 * 3.8 * 21 = 471 W
Windows Total = 693 W

Ceiling = 70 * 0.5 * 21 = 735 W
Air changes = 70 * 2.2 * 0.36 * 1.5 * 21 = 1746 W

Upstairs losses = 5951 W

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

The U value for 100mm of mineral fibre in a pitched roof construction
is 0.36 according to BS 5449.

So in fact Neil's heat loss via this route is less than suggested and
more like

70 x 0.36 x 21 = 529W.

This is about 4% of his total 12.3kW

Increasing the insulation to your suggested level might achieve a U
value of 0.15 taking the heatloss down to 220W.

This represents a difference of 2.4%

Not very interesting in the context of 20% going out through the solid
walls.



Also what
about the hallway which is also upstairs and downstairs.

The only effect that can happen there is to assume that the hallway
downstairs is at downstairs temperature and that the landing above
will achieve the same temperature via convection.

In most houses the upstairs landing might be 15-20% of the total
upstairs area, so in essence the landing becomes 3 degrees warmer than
the bedrooms. the impact is demonstrably marginal. Another corner
case.

Look specifically
at the upper rooms and see the difference.

They look remarkably similar, even accounting for convection from
downstairs.

Also there is the matters of
keeping the upper rooms cool in summer too. 400mm does that wonderfully.
It is a win, win situation.


If you think that that is a win, win then you are missing out on much
bigger prizes.

Somebody once related the following tale to me, which seems apropos.

There were too bulls standing on the top of a hill and below them a
field of cows.

One was always enthusiastic about chasing the latest idea, so he said
"Cor. Look at that lot. Let's run down and f*ck one of them"

The other one said

"Let's walk down and f*ck all of them"



---

..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
The U value for 100mm of mineral fibre in a pitched roof construction
is 0.36 according to BS 5449.

So in fact Neil's heat loss via this route is less than suggested and
more like

70 x 0.36 x 21 = 529W.

This is about 4% of his total 12.3kW

Increasing the insulation to your suggested level might achieve a U
value of 0.15 taking the heatloss down to 220W.

This represents a difference of 2.4%

In fact I deliberately increased the U-value of the loft because I don't
know exactly how much insulation there is throughout the whole thing -
part of it is inaccessible at the moment - and some of it appears to be
somewhat low quality.

On Fri, 23 Jan 2004 11:08:45 -0000, "IMM" wrote:


"Andy Hall" wrote in message

I was going to suggest the Knauf U value calculator normally available
as
a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the moment
as
it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you \re
still
interpreted.

The point is that the house has to be viewed
as upper and lower floors. the
difference in the upper floors is marked
in most houses.

Heatloss through walls of the same construction, accounting for
temperature variation, varies depending on whether you are upstairs or
downstairs?

Grow up! The rooms in the upper floors have a large area that is the
ceiling with a cold loft over in winter and hot loft over in summer.

Yes, and all the exterior walls and windows have an even larger area
that is hot in the summer and cold in the winter.

Insulate the loft heavily and heat loss in these rooms reduces considerably,
giving superior comfort conditions in winter and summer, moreso than the
ground floors.

Please provide the figures to demonstrate that assertion.



If you are saying that adding insulation where there was none before
makes a significant difference to the overall effect in the house, I
will accept it. I don't accept that insulating up to 300-400 mm
rather than 100 or 150 makes a huge difference to the *total* for a
house because the figures don't support that.

If you can demonstrate, for an existing property, (not an
eco-special), with independently verifiable figures and quantitative
references that doing what you propose makes a difference of more than
a very few percent then there is something to discuss.

Otherwise you are just doing your normal arm waving with nothing
substantial to back it up.




You didn't know that did you?



---

..andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 11:41:24 -0000, "Neil Jones"
wrote:


"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

U value of mineral wool of 100mm is 0.36 according to the British
Standard, Neil, so I think you are probably better off than you think
with respect to the roof, and the difference is not as substantial as
this suggests. I reckoned that this would save about 2.5%.



Saving 588W, 5% of the total loss previously. How much does it cost to
buy 70 m2 loft insulation, at a depth of 300mm?

Also what
about the hallway which is also upstairs and downstairs.

What about it?




..andy

To email, substitute .nospam with .gl

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it cost to
buy 70 m2 loft insulation, at a depth of 300mm?

Also what
about the hallway which is also upstairs and downstairs.

What about it?

Must be regarded as a ground floor room.



---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

In article , Imm wrote:
Insulate the loft heavily and heat loss in these rooms reduces
considerably,
^^^^^^^^^^^^

The word you are thinking of is slightly. As has been repeatedly
pointed out, we are currently insulating to levels where providing
any more has a minimal effect.

On the typical 108m2 2-storey house file we supply with our
SuperHeat program the structural heat loss with a roof UV of 0.18
is 111.92W/K which would fall to 105.15 if you could get the
U-value down to 0.05. But at this point with a condensing boiler
the energy split is roughly 33% fabric, 17% ventilation, 33% DHW
and 17% system losses, and the cash saving shown on the SAP
worksheet is £5.78p.a. Most people would rather have a usable loft.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser
http://www.sda.co.uk/qsedbuk.htm

"Andy Hall" wrote in message
...
On Fri, 23 Jan 2004 11:15:14 -0000, "IMM" wrote:


"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Andy Hall" wrote in message
...

It does!!!!!!!!!! The upstairs then is much more well insulated,
warmer
and
consumes less fuel to heat. The upstairs rooms benefit greatly by
heavy
insulation in the loft.

Do I need to do the sums again for
you to demonstrate the point?

Well do them by having a before and after of the ground floor and the
1st
floor.

Here's my house as an exercise:-

Foot print ~ 70m2
Downstairs wall height ~ 2.1m
Upstairs wall height ~ 2.2m
Wall construction:-
downstairs 27 m solid wall construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
upstairs 27 m tile hung lath/plaster construction U-val ~ 2.0
+ 8 m timber clad cavity wall construction U-val ~ 0.6
Ground floor :- thick concrete + screed + covering U-val ~ 0.3
Ceiling Floorbaord/Joist/Plaster U-val ~ 1.6
Loft currently insulated with ~ 100mm mineral wool U-val ~ 0.5

Windows:-
Downstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8
Upstairs
2.2 m2 single glazed timber frames U-val ~ 4.8
5.9 m2 sealed double glazed units in plastic and metal U-val ~ 3.8

Doors:-
6 m2 mixed construction U-val ~ 3.0

Air changes :- 1.5 per hour

Design parameters
=================
Outside temp -3 C

Downstairs temp 21 C (delta-T = 24)
Upstairs temp 18 C (delta-T = 21)

Heat loss - downstairs
======================
Floor = 70 x 0.3 x 24 = 504 W
Walls = (27*2.1 - 5.9 - 3) * 2.0 * 24 ~ 2295 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 2462 W

Windows = 2.2 * 4.8 * 24 = 254 W
+5.9 * 3.8 * 24 = 538 W
Windows Total = 792 W

Doors = 6 * 3 * 24 = 432 W
Ceiling = 70 * 1.6 * 3 = 336 W
Air changes = 70 * 2.1 * 0.36 * 1.5 * 24 = 1896 W

Downstairs losses = 6422 W

Heat loss - upstairs
====================
Floor = 70 x 1.6 x -3 = 336 W
Walls = (27*2.2 - 5.9) * 2.0 * 21 ~ 2247 W
+( 8*2.2 - 2.2) * 0.6 * 21 = 194 W
Walls Total = 2441 W

Windows = 2.2 * 4.8 * 21 = 222 W
+5.9 * 3.8 * 21 = 471 W
Windows Total = 693 W

Ceiling = 70 * 0.5 * 21 = 735 W
Air changes = 70 * 2.2 * 0.36 * 1.5 * 21 = 1746 W

Upstairs losses = 5951 W

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

The U value for 100mm of mineral fibre in a pitched roof construction
is 0.36 according to BS 5449.

So in fact Neil's heat loss via this route is less than suggested and
more like

70 x 0.36 x 21 = 529W.

This is about 4% of his total 12.3kW

Increasing the insulation to your suggested level might achieve a U
value of 0.15 taking the heatloss down to 220W.

This represents a difference of 2.4%

Not very interesting in the context of 20% going out through the solid
walls.



Also what
about the hallway which is also upstairs and downstairs.

The only effect that can happen there is to assume that the hallway
downstairs is at downstairs temperature and that the landing above
will achieve the same temperature via convection.

In most houses the upstairs landing might be 15-20% of the total
upstairs area, so in essence the landing becomes 3 degrees warmer than
the bedrooms. the impact is demonstrably marginal. Another corner
case.

Look specifically
at the upper rooms and see the difference.

They look remarkably similar, even accounting for convection from
downstairs.

Also there is the matters of
keeping the upper rooms cool in summer too. 400mm does that wonderfully.
It is a win, win situation.


If you think that that is a win, win then you are missing out on much
bigger prizes.

You really haven't got it have you?



---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"IMM" wrote in message
...

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it cost
to
buy 70 m2 loft insulation, at a depth of 300mm?


What was the answer to this?

"Andy Hall" wrote in message
news
On Fri, 23 Jan 2004 11:08:45 -0000, "IMM" wrote:


"Andy Hall" wrote in message

I was going to suggest the Knauf U value calculator normally
available
as
a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the
moment
as
it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you \re
still
interpreted.

The point is that the house has to be viewed
as upper and lower floors. the
difference in the upper floors is marked
in most houses.

Heatloss through walls of the same construction, accounting for
temperature variation, varies depending on whether you are upstairs or
downstairs?

Grow up! The rooms in the upper floors have a large area that is the
ceiling with a cold loft over in winter and hot loft over in summer.

Yes, and all the exterior walls and windows have an even larger area
that is hot in the summer and cold in the winter.

They generally do not. Most it is about equal in area. My main bedroom
has a very large ceiling area. More than the walls. And when you take into
account much of the outside walls have build-in wardrobes across them, there
is not much wall area at all compared to ceiling area. Most homes have
built-in floor to ceiling wardrobes these days, with many of them against
outside walls, which gives an extra level of insulation against the outside
walls. Packing in loft insulation for the benefit of the upper rooms is a
win, win, win situation, giving greater benefits to these rooms than others.
It is worth alone just for these rooms.

As I have told you. Last August in a heat wave, the coolest roomin my house
was the main bedroom. The insulatio above proteced it from the 55C in the
loft above. A breeze runningthrough the uper windows, which are beter for
breeze being higher up, and it was very comfortable.

Many selfbuilt homes have the living areas on the upper floors, which makes
much more sense.

Insulate the loft heavily and heat loss in these rooms reduces
considerably,
giving superior comfort conditions in winter and summer, moreso than the
ground floors.

Please provide the figures to demonstrate that assertion.

Depends on the house in question. 90% plus will benefit and many others
will greatly benefit.

If you are saying that adding insulation where there was none before
makes a significant difference to the overall effect in the house, I
will accept it. I don't accept that insulating up to 300-400 mm
rather than 100 or 150 makes a huge difference to the *total* for a
house because the figures don't support that.

You are a thicko! The upper rooms greatly benefit, of which there is
usually 3 or 4 bed and one or two baths. You make the silly mistake of
looking at the whole house and treating it as one with all rooms being
equal. Big mistake.



---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Andy Hall" wrote in message
...
On Fri, 23 Jan 2004 11:41:24 -0000, "Neil Jones"
wrote:


"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

U value of mineral wool of 100mm is 0.36 according to the British
Standard, Neil, so I think you are probably better off than you think
with respect to the roof, and the difference is not as substantial as
this suggests. I reckoned that this would save about 2.5%.

So worth it.


---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Tony Bryer" wrote in message
...
In article , Imm wrote:
Insulate the loft heavily and heat loss in these rooms reduces
considerably,
^^^^^^^^^^^^

The word you are thinking of is slightly. As has been repeatedly
pointed out, we are currently insulating to levels where providing
any more has a minimal effect.

On the typical 108m2 2-storey house file we supply with our
SuperHeat program the structural heat loss with a roof UV of 0.18
is 111.92W/K which would fall to 105.15 if you could get the
U-value down to 0.05. But at this point with a condensing boiler
the energy split is roughly 33% fabric, 17% ventilation, 33% DHW
and 17% system losses, and the cash saving shown on the SAP
worksheet is £5.78p.a. Most people would rather have a usable loft.

You can have both. I do. Look at the benefits to the upper rooms only.
You are looking at the house as one big blob.


---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs
again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it
cost
to
buy 70 m2 loft insulation, at a depth of 300mm?


What was the answer to this?



I'll answer my own question. About £300, as far as I can tell.

For the same price I can get enough boards of 25mm Kingspan to dryline
the solid walls downstairs, which would reduce the U-value to 0.6.

So the heat loss here would become

Walls = (27*2.1 - 5.9 - 3) * 0.6 * 24 = 688 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 855 W
Previous Walls Total = 2462 W

Saving = 1607 W

So I can either spend £300 to save 588 W, (£1.96/W) or I can spend the
same and save 1607 W. (£5.35/W)

If I go for 50mm Kingspan, the price goes up to £400, but the saving
goes to 1870 W. (£2.63/W for the extra £100, which still gives a better
return than more loft insulation).

Alternatively, I could spend another £300 on 25mm Kingspan for the
upstairs and get another 1573 W saving, at £5.24/W.

[If Andy is right, and I'm only saving 392 W with the extra loft
insulation, it's £1.31/W.]

Extra loft insulation comes well down the priority list for my house,
because the cost/Watt saved is easily beaten elsewhere.

"Neil Jones" wrote in message
...

. How much does it
cost
to
buy 70 m2 loft insulation, at a depth of 300mm?


What was the answer to this?



I'll answer my own question. About £300, as far as I can tell.

For the same price I can get enough boards of 25mm Kingspan to dryline
the solid walls downstairs, which would reduce the U-value to 0.6.

So the heat loss here would become

Walls = (27*2.1 - 5.9 - 3) * 0.6 * 24 = 688 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 855 W
Previous Walls Total = 2462 W

Saving = 1607 W

So I can either spend £300 to save 588 W, (£1.96/W) or I can spend the
same and save 1607 W. (£5.35/W)

If I go for 50mm Kingspan, the price goes up to £400, but the saving
goes to 1870 W. (£2.63/W for the extra £100, which still gives a
better
return than more loft insulation).

Alternatively, I could spend another £300 on 25mm Kingspan for the
upstairs and get another 1573 W saving, at £5.24/W.

[If Andy is right, and I'm only saving 392 W with the extra loft
insulation, it's £1.31/W.]

Extra loft insulation comes well down the priority list for my house,
because the cost/Watt saved is easily beaten elsewhere.


Whoops! These are all in Watts saved / £ spent, not the other way
around.

Neil

On Fri, 23 Jan 2004 12:16:12 -0000, "IMM" wrote:


"Andy Hall" wrote in message
news
On Fri, 23 Jan 2004 11:08:45 -0000, "IMM" wrote:


"Andy Hall" wrote in message

I was going to suggest the Knauf U value calculator normally
available
as
a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the
moment
as
it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you \re
still
interpreted.

The point is that the house has to be viewed
as upper and lower floors. the
difference in the upper floors is marked
in most houses.

Heatloss through walls of the same construction, accounting for
temperature variation, varies depending on whether you are upstairs or
downstairs?

Grow up! The rooms in the upper floors have a large area that is the
ceiling with a cold loft over in winter and hot loft over in summer.

Yes, and all the exterior walls and windows have an even larger area
that is hot in the summer and cold in the winter.

They generally do not. Most it is about equal in area.

Nonsense.

Detached House. 7m x 7m x 5m high
Outside wall area 140 sq metres
Ceiling area 49 sq metres

Semi detached house 7m x 5m frontage x 5m high
outside wall area 85 sqm
ceiling area 35 sqm

Bungalow 10m x 7m x 2.5m high
outside wall area 85 sqm
ceiling 70sqm

Terraced house 15m x 5m *5m high
outside wall area 50sqm (assuming small front and back walls)
ceiling area 75sqm.

This is the only case, and even then there is a question mark over the
party walls which should probably be treated as a third to a half the
heat loss of an outside wall.


My main bedroom
has a very large ceiling area. More than the walls.

By counting three walls as internal? That's a crock because for the
house as a whole there will be 2,3 or 4 external walls overall.


And when you take into
account much of the outside walls have build-in wardrobes across them, there
is not much wall area at all compared to ceiling area. Most homes have
built-in floor to ceiling wardrobes these days, with many of them against
outside walls, which gives an extra level of insulation against the outside
walls. Packing in loft insulation for the benefit of the upper rooms is a
win, win, win situation, giving greater benefits to these rooms than others.
It is worth alone just for these rooms.

This is just pulling things out of the air.




As I have told you. Last August in a heat wave, the coolest roomin my house
was the main bedroom. The insulatio above proteced it from the 55C in the
loft above. A breeze runningthrough the uper windows, which are beter for
breeze being higher up, and it was very comfortable.

Maybe you should try mirrors on the ceiling as well......



Many selfbuilt homes have the living areas on the upper floors, which makes
much more sense.

Insulate the loft heavily and heat loss in these rooms reduces
considerably,
giving superior comfort conditions in winter and summer, moreso than the
ground floors.

Please provide the figures to demonstrate that assertion.

Depends on the house in question. 90% plus will benefit and many others
will greatly benefit.

Figures? Otherwise this is just armwaving again.




If you are saying that adding insulation where there was none before
makes a significant difference to the overall effect in the house, I
will accept it. I don't accept that insulating up to 300-400 mm
rather than 100 or 150 makes a huge difference to the *total* for a
house because the figures don't support that.

You are a thicko! The upper rooms greatly benefit, of which there is
usually 3 or 4 bed and one or two baths. You make the silly mistake of
looking at the whole house and treating it as one with all rooms being
equal. Big mistake.

I've done heating calculations in fine detail for different
properties, counting losses and gains through internal surfaces as
well.

The temperature ranges for different rooms by recommendation range
from 16 to 23 degrees and I suspect a lot of people run with less
than that. If you plug in these factors for most properties, the
heat flow internally is generally relatively small in comparison with
flows through external surfaces.





---

..andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 12:16:54 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Fri, 23 Jan 2004 11:41:24 -0000, "Neil Jones"
wrote:


"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

U value of mineral wool of 100mm is 0.36 according to the British
Standard, Neil, so I think you are probably better off than you think
with respect to the roof, and the difference is not as substantial as
this suggests. I reckoned that this would save about 2.5%.

So worth it.

ROTFL.




---

..andy

To email, substitute .nospam with .gl

"Neil Jones" wrote in message
...

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs
again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it
cost
to
buy 70 m2 loft insulation, at a depth of 300mm?


What was the answer to this?



I'll answer my own question. About £300, as far as I can tell.

For the same price I can get enough boards of 25mm Kingspan to dryline
the solid walls downstairs, which would reduce the U-value to 0.6.

So the heat loss here would become

Walls = (27*2.1 - 5.9 - 3) * 0.6 * 24 = 688 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 855 W
Previous Walls Total = 2462 W

Saving = 1607 W

So I can either spend £300 to save 588 W, (£1.96/W) or I can spend the
same and save 1607 W. (£5.35/W)

If I go for 50mm Kingspan, the price goes up to £400, but the saving
goes to 1870 W. (£2.63/W for the extra £100, which still gives a better
return than more loft insulation).

Alternatively, I could spend another £300 on 25mm Kingspan for the
upstairs and get another 1573 W saving, at £5.24/W.

[If Andy is right, and I'm only saving 392 W with the extra loft
insulation, it's £1.31/W.]

Extra loft insulation comes well down the priority list for my house,
because the cost/Watt saved is easily beaten elsewhere.

You are looking at the house as a whole again. Duh! The extra insulation
benefits greatly the upper rooms.

The loft insulation is the depth over and above the 100mm. You have to
take into account the fixing of the downstairs wall Kingspan. Loft
insulation is cheap and easy, so do it. Also do downstairs too with
Kingspan, but the installation cost is greater.




---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

On Fri, 23 Jan 2004 12:05:18 -0000, "Neil Jones"
wrote:


"IMM" wrote in message
...

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it cost
to
buy 70 m2 loft insulation, at a depth of 300mm?


What was the answer to this?



Supawrap from BuilderCenter is £12.66 exc. for 4sqm and 150mm thick.

So for 70sqm coverage you would need 35 rolls to achieve a thickness
of 300mm at a total cost of £520. This appears to be the cheapest
they have on a volume basis. You could probably get 20% discount,
so say £400.

On your assumed U value of 0.5, which is worse than it probably is,
you are saving 588W worst case.

If the temperatures were worst case all year all day then at 1.4p a
unit for gas you would save £72 per annum.

If you work on the 10 degree average which is closer to reality, then
the loss is going to be 8/21 x the figure - i.e. 220W and £27 per
annum.

In reality, the insulation you have is probably better than 0.5 and
the saving perhaps £20 per year.

A 20 year payback or 10 years if energy costs double today....

Doesn't seem interesting to me.

I'd think about using even a thin Celotex layer on a few outside walls
during redecoration first, if that's practicable. This is about
£5/sqm for 50mm, 25mm is about £3.50.





..andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 12:47:50 -0000, "Neil Jones"
wrote:


"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs
again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it
cost
to
buy 70 m2 loft insulation, at a depth of 300mm?


What was the answer to this?



I'll answer my own question. About £300, as far as I can tell.

For the same price I can get enough boards of 25mm Kingspan to dryline
the solid walls downstairs, which would reduce the U-value to 0.6.

So the heat loss here would become

Walls = (27*2.1 - 5.9 - 3) * 0.6 * 24 = 688 W
+( 8*2.1 - 2.2 - 3) * 0.6 * 24 = 167 W
Walls Total = 855 W
Previous Walls Total = 2462 W

Saving = 1607 W

So I can either spend £300 to save 588 W, (£1.96/W) or I can spend the
same and save 1607 W. (£5.35/W)

If I go for 50mm Kingspan, the price goes up to £400, but the saving
goes to 1870 W. (£2.63/W for the extra £100, which still gives a better
return than more loft insulation).

Alternatively, I could spend another £300 on 25mm Kingspan for the
upstairs and get another 1573 W saving, at £5.24/W.

[If Andy is right, and I'm only saving 392 W with the extra loft
insulation, it's £1.31/W.]

Extra loft insulation comes well down the priority list for my house,
because the cost/Watt saved is easily beaten elsewhere.


Exactly. See my other post. Slightly different prices, but the
principle is the same.









..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
Supawrap from BuilderCenter is £12.66 exc. for 4sqm and 150mm thick.

So for 70sqm coverage you would need 35 rolls to achieve a thickness
of 300mm at a total cost of £520. This appears to be the cheapest
they have on a volume basis. You could probably get 20% discount,
so say £400.

On your assumed U value of 0.5, which is worse than it probably is,
you are saving 588W worst case.

If the temperatures were worst case all year all day then at 1.4p a
unit for gas you would save £72 per annum.

If you work on the 10 degree average which is closer to reality, then
the loss is going to be 8/21 x the figure - i.e. 220W and £27 per
annum.

In reality, the insulation you have is probably better than 0.5 and
the saving perhaps £20 per year.

A 20 year payback or 10 years if energy costs double today....

Doesn't seem interesting to me.

I'd think about using even a thin Celotex layer on a few outside walls
during redecoration first, if that's practicable. This is about
£5/sqm for 50mm, 25mm is about £3.50.


Exactly, although I'm looking at Kingspan rather than Celotex.

"Andy Hall" wrote in message
...
On Fri, 23 Jan 2004 12:16:12 -0000, "IMM" wrote:


"Andy Hall" wrote in message
news
On Fri, 23 Jan 2004 11:08:45 -0000, "IMM" wrote:


"Andy Hall" wrote in message

I was going to suggest the Knauf U value calculator normally
available
as
a
trial version from
http://www.knaufinsulation.co.uk/ but it is unavailable at the
moment
as
it
is apparently being updated.

It may be worthwhile checking the site in a week or so if you
\re
still
interpreted.

The point is that the house has to be viewed
as upper and lower floors. the
difference in the upper floors is marked
in most houses.

Heatloss through walls of the same construction, accounting for
temperature variation, varies depending on whether you are upstairs
or
downstairs?

Grow up! The rooms in the upper floors have a large area that is the
ceiling with a cold loft over in winter and hot loft over in summer.

Yes, and all the exterior walls and windows have an even larger area
that is hot in the summer and cold in the winter.

They generally do not. Most it is about equal in area.

Nonsense.

Detached House. 7m x 7m x 5m high
Outside wall area 140 sq metres
Ceiling area 49 sq metres

You have to look at individual upper rooms.

My main bedroom
has a very large ceiling area. More than the walls.

By counting three walls as internal? That's a crock

Not in that room it isn't.

And when you take into
account much of the outside walls have build-in wardrobes across them,
there
is not much wall area at all compared to ceiling area. Most homes have
built-in floor to ceiling wardrobes these days, with many of them against
outside walls, which gives an extra level of insulation against the
outside
walls. Packing in loft insulation for the benefit of the upper rooms is a
win, win, win situation, giving greater benefits to these rooms than
others.
It is worth alone just for these rooms.

This is just pulling things out of the air.

It is NOT! It is looking at the house realistically, instead of one blob of
a box.

As I have told you. Last August in a heat wave, the coolest roomin my
house
was the main bedroom. The insulatio above proteced it from the 55C in
the
loft above. A breeze runningthrough the uper windows, which are beter for
breeze being higher up, and it was very comfortable.

Maybe you should try mirrors on the ceiling as well......

If these wo rk then I will. Do you have a URL?

Depends on the house in question. 90% plus will benefit and many others
will greatly benefit.

Figures? Otherwise this is just armwaving again.

Figures? For what type of house? Do they all one bedroom wall top to toe
built-in cupboards? Etc, etc.

If you are saying that adding insulation where there was none before
makes a significant difference to the overall effect in the house, I
will accept it. I don't accept that insulating up to 300-400 mm
rather than 100 or 150 makes a huge difference to the *total* for a
house because the figures don't support that.

You are a thicko! The upper rooms greatly benefit, of which there is
usually 3 or 4 bed and one or two baths. You make the silly mistake of
looking at the whole house and treating it as one with all rooms being
equal. Big mistake.

I've done heating calculations in fine detail for different
properties, counting losses and gains through internal surfaces as
well.

The devil is in the detail. Your detail was not fine enough. It is worth
having high levels of insulation in my house just to keep the bedrooms warm
and cool. For those who have an upper room as an office the benefits are
even greater. Keeping bedrooms cool is good in preventing cots deaths too.
I'm sure the lower rooms didn't benefit too much.

Even in the depths of winter, once the bedrooms are up to temperature, the
TRVs virtually stay off all day. I have the bedroom doors always closed, so
no heat is rising from downstairs into them.




---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Andy Hall" wrote in message
news
On Fri, 23 Jan 2004 12:16:54 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Fri, 23 Jan 2004 11:41:24 -0000, "Neil Jones"
wrote:


"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

U value of mineral wool of 100mm is 0.36 according to the British
Standard, Neil, so I think you are probably better off than you think
with respect to the roof, and the difference is not as substantial as
this suggests. I reckoned that this would save about 2.5%.

So worth it.

ROTFL.

You did? Do you laugh at the Vicar of Dibley too?


---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Andy Hall" wrote in message
...
On Fri, 23 Jan 2004 12:05:18 -0000, "Neil Jones"
wrote:


"IMM" wrote in message
...

"Neil Jones" wrote in message
...

"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

Saving 588W, 5% of the total loss previously. How much does it cost
to
buy 70 m2 loft insulation, at a depth of 300mm?


What was the answer to this?



Supawrap from BuilderCenter is £12.66 exc. for 4sqm and 150mm thick.

So for 70sqm coverage you would need 35 rolls to achieve a thickness
of 300mm at a total cost of £520. This appears to be the cheapest
they have on a volume basis. You could probably get 20% discount,
so say £400.

On your assumed U value of 0.5, which is worse than it probably is,
you are saving 588W worst case.

If the temperatures were worst case all year all day then at 1.4p a
unit for gas you would save £72 per annum.

If you work on the 10 degree average which is closer to reality, then
the loss is going to be 8/21 x the figure - i.e. 220W and £27 per
annum.

In reality, the insulation you have is probably better than 0.5 and
the saving perhaps £20 per year.

A 20 year payback or 10 years if energy costs double today....

Doesn't seem interesting to me.

Because you haven't looked at it properly.



---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Neil Jones" wrote in message
...

"Andy Hall" wrote in message
Supawrap from BuilderCenter is £12.66 exc. for 4sqm and 150mm thick.

So for 70sqm coverage you would need 35 rolls to achieve a thickness
of 300mm at a total cost of £520. This appears to be the cheapest
they have on a volume basis. You could probably get 20% discount,
so say £400.

On your assumed U value of 0.5, which is worse than it probably is,
you are saving 588W worst case.

If the temperatures were worst case all year all day then at 1.4p a
unit for gas you would save £72 per annum.

If you work on the 10 degree average which is closer to reality, then
the loss is going to be 8/21 x the figure - i.e. 220W and £27 per
annum.

In reality, the insulation you have is probably better than 0.5 and
the saving perhaps £20 per year.

A 20 year payback or 10 years if energy costs double today....

Doesn't seem interesting to me.

I'd think about using even a thin Celotex layer on a few outside walls
during redecoration first, if that's practicable. This is about
£5/sqm for 50mm, 25mm is about £3.50.


Exactly, although I'm looking at Kingspan rather than Celotex.

Do both. Loft and walls.



---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

You are looking at the house as a whole again. Duh! The extra
insulation
benefits greatly the upper rooms.

Of course I'm looking at the whole house. I pay the whole gas bill,
which covers the heating for the whole house. If I only paid for my
study, and my wife paid for the rest, then I'd turn the radiator off in
that room and buy a few jumpers.

The loft insulation is the depth over and above the 100mm.
That's right - the extra 300mm required to take it up to the 400mm you
requested. Well spotted.

You have to
take into account the fixing of the downstairs wall Kingspan.

I did, actually, because the costs I have been quoted for the Kingspan
alone are less than I mentioned, but I allowed extra for battening etc.

Loft
insulation is cheap and easy, so do it.
As I have shown, the loft insulation is the same cost and has a much
smaller benefit, so it is lower priority.

Also do downstairs too with
Kingspan, but the installation cost is greater.


Do you think I am made of money? If my budget is (lets say) £400, it's
either/or, not both. Insulating the downstairs wins hands down because
it has a much bigger effect for the same outlay.

Regards

Neil

"IMM" wrote in message
...

"Neil Jones" wrote in message
...

"Andy Hall" wrote in message
Supawrap from BuilderCenter is £12.66 exc. for 4sqm and 150mm
thick.

So for 70sqm coverage you would need 35 rolls to achieve a
thickness
of 300mm at a total cost of £520. This appears to be the cheapest
they have on a volume basis. You could probably get 20%
discount,
so say £400.

On your assumed U value of 0.5, which is worse than it probably
is,
you are saving 588W worst case.

If the temperatures were worst case all year all day then at 1.4p
a
unit for gas you would save £72 per annum.

If you work on the 10 degree average which is closer to reality,
then
the loss is going to be 8/21 x the figure - i.e. 220W and £27 per
annum.

In reality, the insulation you have is probably better than 0.5
and
the saving perhaps £20 per year.

A 20 year payback or 10 years if energy costs double today....

Doesn't seem interesting to me.

I'd think about using even a thin Celotex layer on a few outside
walls
during redecoration first, if that's practicable. This is about
£5/sqm for 50mm, 25mm is about £3.50.


Exactly, although I'm looking at Kingspan rather than Celotex.

Do both. Loft and walls.


Do you live in the real world? Money is finite, and so we prioritise.

"Neil Jones" wrote in message ...
"Andy Hall" wrote in message
...

These are quite typical numbers, Neil.

I guess that this is an older house with a new extension?

Yes. The old part is 500 year old, or so. The extension was bulit in
1995.

It's interesting to note that the losses are close to being the same
upstairs and downstairs.

Just to add my 2p. I insulated my loft to 150mm. I had lots of
insulation over so doubled up over the main bedroom where I sleep.
This bedroom is warmer in winter, and thankfully last summer a lot
cooler. I could always sleep while neighbours complained they were too
hot to sleep in similar houses to mine. When I have time I will do
the whole loft to at least 300mm. If I can get a decent deal maybe
thicker. To me it will be worth it. I don't know about economics as I
haven't kept a watch on the gas bills. To me that is not the real
issue during a hot summer.

Quite.



.andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 13:59:48 -0000, "IMM" wrote:




They generally do not. Most it is about equal in area.

Nonsense.

Detached House. 7m x 7m x 5m high
Outside wall area 140 sq metres
Ceiling area 49 sq metres

You have to look at individual upper rooms.

OK. So present a worked example of a typical house of today, yours
if you like, and show figures for why you believe this is significant
in the context of this discussion.

Obviously this is important in terms of heat emitter sizing but that
is not the discussion here



My main bedroom
has a very large ceiling area. More than the walls.

By counting three walls as internal? That's a crock

Not in that room it isn't.

OK, so why don't you present some real figures and workings to
demonstrate your point.


And when you take into
account much of the outside walls have build-in wardrobes across them,
there
is not much wall area at all compared to ceiling area. Most homes have
built-in floor to ceiling wardrobes these days, with many of them against
outside walls, which gives an extra level of insulation against the
outside
walls. Packing in loft insulation for the benefit of the upper rooms is a
win, win, win situation, giving greater benefits to these rooms than
others.
It is worth alone just for these rooms.

This is just pulling things out of the air.

It is NOT! It is looking at the house realistically, instead of one blob of
a box.

On that argument you would insulate different rooms to different
degrees.

If there were a real issue here, rooms would be insulated from one
another in addition to anything related to external surfaces.
Unless one wants to deliberately maintain a temperature of one room at
a significantly different temperature from the others, insulation
between them is not used, simply because the overall differences are
6-8 degrees.



As I have told you. Last August in a heat wave, the coolest roomin my
house
was the main bedroom. The insulatio above proteced it from the 55C in
the
loft above. A breeze runningthrough the uper windows, which are beter for
breeze being higher up, and it was very comfortable.

Maybe you should try mirrors on the ceiling as well......

If these wo rk then I will. Do you have a URL?


Depends on the house in question. 90% plus will benefit and many others
will greatly benefit.

Figures? Otherwise this is just armwaving again.

Figures? For what type of house? Do they all one bedroom wall top to toe
built-in cupboards? Etc, etc.

Just provide a typical example with worked figures to demonstrate your
point if you believe there is one.



If you are saying that adding insulation where there was none before
makes a significant difference to the overall effect in the house, I
will accept it. I don't accept that insulating up to 300-400 mm
rather than 100 or 150 makes a huge difference to the *total* for a
house because the figures don't support that.

You are a thicko! The upper rooms greatly benefit, of which there is
usually 3 or 4 bed and one or two baths. You make the silly mistake of
looking at the whole house and treating it as one with all rooms being
equal. Big mistake.

I've done heating calculations in fine detail for different
properties, counting losses and gains through internal surfaces as
well.

The devil is in the detail. Your detail was not fine enough. It is worth
having high levels of insulation in my house just to keep the bedrooms warm
and cool. For those who have an upper room as an office the benefits are
even greater. Keeping bedrooms cool is good in preventing cots deaths too.
I'm sure the lower rooms didn't benefit too much.

So please provide the detailed data and worked examples to justify
these assertions. Yes I know that cooler bedrooms impact SIDS so you
don't need to search Google for those numbers. Stick to the point
of providing the detailed data on the extent to which insulation at
your recommended 350-600mm makes the large difference that you claim
relative to 100-150mm, stated in the context of the house in total.





Even in the depths of winter, once the bedrooms are up to temperature, the
TRVs virtually stay off all day. I have the bedroom doors always closed, so
no heat is rising from downstairs into them.




---

..andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 14:00:37 -0000, "IMM" wrote:


"Andy Hall" wrote in message
news
On Fri, 23 Jan 2004 12:16:54 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Fri, 23 Jan 2004 11:41:24 -0000, "Neil Jones"
wrote:


"IMM" wrote in message
...

"Neil Jones" wrote in message
[snip]

Total losses for house = 12.3kW

Downstairs losses are 51.9% of total losses from house.

Losses through:-

Ground floor 4%
Downstairs solid wall 19%
Downstairs cavity wall 1%
Downstairs windows 6%
Ceiling to upstairs 3%

Roof 6%
Upstairs solid wall 18%
Upstairs cavity wall 2%
Upstairs windows 6%

Increase the loft insulation to 350-400mm and do the calcs again.

OK.
Thermal conductivity of mineral wool = 0.038

1/0.5 + (0.3/0.038) = 2 + 7.9 = 9.9.

U val = 1/9.9 ~ 0.10

Losses through ceiling reduced to 70 * 0.10 * 21 = 147W

U value of mineral wool of 100mm is 0.36 according to the British
Standard, Neil, so I think you are probably better off than you think
with respect to the roof, and the difference is not as substantial as
this suggests. I reckoned that this would save about 2.5%.

So worth it.

ROTFL.

You did? Do you laugh at the Vicar of Dibley too?

No, just at your notion that 2.5% is meaningful when compared to a
context of over 30% for the solid walls.


---

..andy

To email, substitute .nospam with .gl

On Fri, 23 Jan 2004 14:03:11 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Fri, 23 Jan 2004 12:05:18 -0000, "Neil Jones"


A 20 year payback or 10 years if energy costs double today....

Doesn't seem interesting to me.

Because you haven't looked at it properly.

OK so present the hard data with numbers to justify that assertion.
A complete example as I did and as Neil did separately.






---

..andy

To email, substitute .nospam with .gl

On 23 Jan 2004 07:12:33 -0800, (timegoesby)
wrote:

"Neil Jones" wrote in message ...
"Andy Hall" wrote in message
...

These are quite typical numbers, Neil.

I guess that this is an older house with a new extension?

Yes. The old part is 500 year old, or so. The extension was bulit in
1995.

It's interesting to note that the losses are close to being the same
upstairs and downstairs.

Just to add my 2p. I insulated my loft to 150mm. I had lots of
insulation over so doubled up over the main bedroom where I sleep.
This bedroom is warmer in winter, and thankfully last summer a lot
cooler.

As compared with having nothing? It would be. That is certainly
worth doing but was not the point.


I could always sleep while neighbours complained they were too
hot to sleep in similar houses to mine.

With how much insulation?

When I have time I will do
the whole loft to at least 300mm. If I can get a decent deal maybe
thicker. To me it will be worth it. I don't know about economics as I
haven't kept a watch on the gas bills. To me that is not the real
issue during a hot summer.

That's fine if you want to do it, but there is nothing to support that
just doubling the insulation like this is going to make any
significant difference to what you have now.



Quite.



.andy

To email, substitute .nospam with .gl

..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Fri, 23 Jan 2004 13:59:48 -0000, "IMM" wrote:




They generally do not. Most it is about equal in area.

Nonsense.

Detached House. 7m x 7m x 5m high
Outside wall area 140 sq metres
Ceiling area 49 sq metres

You have to look at individual upper rooms.

OK. So present a worked example of a typical house of today, yours
if you like, and show figures for why you believe this is significant
in the context of this discussion.

Obviously this is important in terms of heat emitter sizing but that
is not the discussion here

My main bedroom
has a very large ceiling area. More than the walls.

By counting three walls as internal? That's a crock

Not in that room it isn't.

OK, so why don't you present some real figures and workings to
demonstrate your point.

NO need, common sense prevails.

And when you take into
account much of the outside walls have build-in wardrobes across them,
there
is not much wall area at all compared to ceiling area. Most homes have
built-in floor to ceiling wardrobes these days, with many of them
against
outside walls, which gives an extra level of insulation against the
outside
walls. Packing in loft insulation for the benefit of the upper rooms
is a
win, win, win situation, giving greater benefits to these rooms than
others.
It is worth alone just for these rooms.

This is just pulling things out of the air.

It is NOT! It is looking at the house realistically, instead of one blob
of
a box.

On that argument you would insulate
different rooms to different degrees.

Could be. You could do all the bedrooms to 400mm and 200mm the rest.

If there were a real issue here, rooms would be insulated from one
another in addition to anything related to external surfaces.
Unless one wants to deliberately maintain a temperature of one room at
a significantly different temperature from the others, insulation
between them is not used, simply because the overall differences are
6-8 degrees.

Most walls have some sort of built-in insulation.

As I have told you. Last August in a heat wave, the coolest roomin
my
house
was the main bedroom. The insulatio above proteced it from the 55C in
the
loft above. A breeze runningthrough the uper windows, which are beter
for
breeze being higher up, and it was very comfortable.

Maybe you should try mirrors on the ceiling as well......

If these wo rk then I will. Do you have a URL?

Depends on the house in question. 90% plus will benefit and many
others
will greatly benefit.

Figures? Otherwise this is just armwaving again.

Figures? For what type of house? Do they all one bedroom wall top to
toe
built-in cupboards? Etc, etc.

Just provide a typical example with worked
figures to demonstrate your
point if you believe there is one.

Just use some common sense. Bedrooms have a large loft ceiling area with a
very cold or hot loft above. Insulating these to high degrees pays dividends
in the particular rooms below.

If you are saying that adding insulation where there was none
before makes a significant difference to the overall effect in the
house, I
will accept it. I don't accept that insulating up to 300-400 mm
rather than 100 or 150 makes a huge difference to the *total* for a
house because the figures don't support that.

You are a thicko! The upper rooms greatly benefit, of which there is
usually 3 or 4 bed and one or two baths. You make the silly mistake
of
looking at the whole house and treating it as one with all rooms being
equal. Big mistake.

I've done heating calculations in fine detail for different
properties, counting losses and gains through internal surfaces as
well.

The devil is in the detail. Your detail was not fine enough. It is worth
having high levels of insulation in my house just to keep the bedrooms
warm
and cool. For those who have an upper room as an office the benefits
are
even greater. Keeping bedrooms cool is good in preventing cots deaths
too.
I'm sure the lower rooms didn't benefit too much.

So please provide the detailed
data and worked examples to justify
these assertions.

Just use some common sense, instead of just looking at a Myson heatless
programme.

Yes I know that cooler bedrooms impact SIDS so you
don't need to search Google for those numbers. Stick to the point
of providing the detailed data on the extent to which insulation at
your recommended 350-600mm makes the large difference that you claim
relative to 100-150mm, stated in the context of the house in total.

Even in the depths of winter, once the bedrooms are up to temperature,
the
TRVs virtually stay off all day. I have the bedroom doors always closed,
so
no heat is rising from downstairs into them.



---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004

"Andy Hall" wrote in message
news
On Fri, 23 Jan 2004 14:03:11 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .
On Fri, 23 Jan 2004 12:05:18 -0000, "Neil Jones"


A 20 year payback or 10 years if energy costs double today....

Doesn't seem interesting to me.

Because you haven't looked at it properly.

OK so present the hard data with numbers to justify that assertion.
A complete example as I did and as Neil did separately.

Apply some common sense and don't keep relying on a Myson program.


---
--

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.564 / Virus Database: 356 - Release Date: 19/01/2004