Construction and adjacency lists every wall of the room plan, then the ceiling and the floor. Each row shows its transmission Load, its U and its Gross area beside the construction that gives them.
- 1
For each surface, choose its Insulation and Thickness.
- 2
Choose its Adjacency: exterior in the sun or shaded, an adjacent conditioned space, an adjacent unconditioned interior, or ground contact for a floor.
- 3
To set several walls at once, tick them or choose Select all walls, then pick the insulation, thickness or adjacency above the table. The copy button on a wall gives it the same construction as the wall before it.
- 4
Under Room, set the Ground temp for a ground-contact floor and the Hemisphere for the sun allowance.
What each adjacency needs
- Exterior — sun exposed asks for the surface colour. Kelvin adds a sun allowance for the wall's facing and colour, and the room's Hemisphere sets which wall faces the equator: the north wall in Australia.
- Exterior — shaded is taken at the room's design ambient.
- Adjacent conditioned space asks for that space's temperature. It starts at a page default with no cited source.
- Adjacent unconditioned interior is taken a little below the room's design ambient unless you enter its temperature. That default has no cited source, and a roof void or plant space in summer runs well above ambient, so enter it.
- Ground contact (floor) is taken at the Ground temp on the sheet, with no outside surface film.
Where the U-value comes from
U is worked from the panel core's conductivity and thickness, with a surface film resistance on each face. Each insulation type carries an aged conductivity from the ASHRAE Refrigeration Handbook Ch. 24, except mineral wool, whose figure is Kelvin's own assumption, and the table says which.
To use the panel maker's declared aged conductivity, type it under the surface's insulation and name the datasheet it comes from. The load build-up and the report then name that source. Clear the figure to go back to the default.
A wall's load is net of its door openings. Each door leaf conducts on its own line in the load build-up, at the U entered in the doors table, or at its wall's U when that is blank.