1970's Build U Values

Following previous message "Central Heating Design - Help Please", can anyone comment on U Values for the following features please? I have two sources of reference, the Screwfix site and Plumbing and Heating by Treloar. These seem to conflict and, when I research other sources, I find these don't tally with either of the above. Is there a definitive source for this information? If so can someone please confirm or revise the following feature values for me (W/m2 Deg C)?
Walls U Value
External Wall - 11" brick-block cavity uninsulated. 1 Internal Wall - plaster, 4.5" brick, plaster 2.2 Plasterboard, 2" eggcrate cavity, plasterboard 2 (guessed) External Wall - 11" brick-block cavity insulated. 0.7
Floors
Ground Floor - Solid Concrete 0.8 Int Floors - Floorboard, 8" joist, Plasterboard 1.7 (heat flow up) Int Floors - Floorboard, 8" joist, Plasterboard 1.5 (heat flow down)
Roof
Pitched with felt - 100mm insulation 0.34 Pitched with felt - 50mm insulation unknown Flat roof - no insulation 1.2
DG Windows/doors uPVC 3
Thanks again for all help given previously
Phil
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On Wed, 27 Oct 2004 13:16:32 +0100, "TheScullster" <phil-at-dropthespam.com> wrote:>Following previous message "Central Heating Design - Help Please", can

My table (from HVAC guide) has 0.87 for this assuming 13mm plaster

1.76 for this one

Generous, possibly a bit less

If it's aerated blocks and mineral wool slab, 0.42

You have to take external walls into account separately here. I have tables of U values for this which are determined from the number and lengths of external walls and their positions. Assuming uninsulated floor, the worst case is 1.15. Best can be as low as 0.39 You could assume the worst case for this purpose if you want. Alternatively, if you post the relevant room wall lengths and what joins what, I can look up the numbers for you.

Yes.
Yes
Doubling the above to 0.7 would be a reasonable assumption for this.

I have 1.6

Yes for a wooden door. For a DG unit about 2.8 for standard glass, 2.1 for low-E.

Don't forget that the internal surfaces are not going to be that important unless you are going to have huge temperature differences between rooms. Heat gain and loss room to room will not usually be a lot; so don't sweat for the last 10W.
.andy
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Andy
Many thanks for your time on this. From the figures you give I am a little more reassured.
However I would appreciate it if you could look up the following:
Floors
All floors are uninsulated ie plain concrete (due to pipe leaks we even had to lift all the original vinyl tiles!) The basic house dimensions are: 8m square in plan with front elevation facing approx east There is also a single storey kitchen extension to the north which has three exposed walls - north wall 5.5m long and east/west walls 4m long. Finally, our room is over a garage, constructed in an extension before we bought the property. Do you know the likely floor construction for this room bearing in mind building regs requirements and hence the likely U Value for heat flow down from this room? The garage ceiling has been plastered with a plaster board "return" down the wall which adjoins the original house about 2 ft deep. Presumably the joist cavities will have been insulated to meet regs (it certainly doesn't feel like it as the cold weather arrives!)
Thanks again
Phil
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