Check Part L building compliance

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Unheated pitched roof

Provide a name for this unheated pitched roof so it can be identified later
Net area of the opaque building element. For an unheated pitched roof this input must be for the ceiling.

Guidance (opens in another window)

Tilt angle of the surface from horizontal, between 0 and 180, where 0 means the external surface is facing up, 90 means the external surface is vertical and 180 means the external surface is facing down

180 = floors
0 = ceilings

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Orientation measurement

To define an object's orientation, measure the angle of its outside face clockwise from true North, accurate to the nearest degree.

For unheated pitched roof, model the length of the roof
For unheated pitched roof, model the width of the roof.
The distance between the ground and the lowest edge of the roof.
Solar absorption coefficient at the external surface (dimensionless), the proportion of solar radiation which is absorbed. Decimal between 0-1.
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0.3
Light colour

0.6
Intermediate colour

0.9
Dark colour

For an unheated pitched roof, input the combined value of the ceiling and roof
Areal heat capacity of roof and ceiling
For an unheated pitched roof, input the combined value of the ceiling and roof
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Very lightLight board or plastic
Light5-10 cm lightweight brick or concrete
Medium10-20 cm lightweight brick or concrete
Heavy7-12 cm solid brick or heavyweight concrete
Very heavyMore than 12 cm solid brick or heavyweight concrete
Mass distribution class of roof and ceiling
For an unheated pitched roof, input the combined value of the ceiling and roof
Guidance (opens in another window)
Construction with external thermal insulation (main mass component near inside surface), or equivalent
Construction with internal thermal insulation (main mass component near outside surface), or equivalent
Construction with thermal insulation in between two main mass components, or equivalent
Uninsulated construction (e.g. solid or hollow bricks, heavy or lightweight concrete, or lightweight construction with negligible mass (e.g. steel sandwich panel), or equivalent
Construction with both internal and external insulation (main mass component concentrated near centre of construction), or equivalent