Andrew Gabriel wrote:

I calculated 875W for a bathroom 1.2m x 2.4m, 9" brick walls
(two external), insulated ceiling, small double glazed window,

That reminds me... I did a set of calcs for our place prior to doing the
loft conversion etc. The existing bathroom came out thus:

Surface Air
Area Tdelta u-val Loss Change Vol

Land wall 4.83 6 1.2 35 0.50 10
office wall 4.6 4 1.2 22
side wall 4.6 25 2.2 253
rear wall 2.83 25 2.2 156
window 2 25 2.9 145
floor 4.2 4 1.5 25
ceiling 4.2 4 1.9 32

Total 668 43 711

So 711W for a simlar sized room - two 10" solid exterior walls, two
internal stud walls, kitchen under, loft over.

--
Cheers,

John.

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