On Fri, 5 Sep 2008 22:06:42 +0100, "Roger Mills"
wrote:

Yes, or even less. Very few systems with conventional boilers run at a dT of
60 - 55 is more usual.

Sorry to start this up again but I have been using the Barlo heat loss
program and see it has an option to set water temperature. Does it
matter what this is set to? I presume that it makes no difference to
the room heat loss calculation but is only used if you ask it to
select appropriate radiators from the Barlo range?

I have tried the Myson program and it gives slighly lower heat losses.
Any idea which program is nearest the mark?

I notice neither program asks whether the room is north facing. Isn't
this significant?

I'm not quite sure what materials to list my walls as. Am I right to
think that the downstairs ceiling/upstairs floor should be selected as
floorboard/joist/plaster where I have a joist with a floorboard on one
side and plasterboard the other?

I know three walls of the house are cavity with a brick outside and
breeze block inside so I guess that's the brick/breeze cavity option?

The problem is that the front of the house is tile clad on the
outside, with who knows what behind it, I guess a single breeze block?
What would this be described as?

Thanks,
Stephen.