Convention 3.01 - Light Pipes

The modelling of light pipes using SBEM will only be considered where the pipes do not pass through acomplete building storey in order to serve the storey below; in these circumstances consideration should begiven to the use of a dynamic simulation model in order to model correctly. Where this is not the case lightpipes should be modelled in SBEM as follows:-

• Light pipes will be modelled as roof lights using the glazing type ‘Roof light, skylight, twin skin’ with‘no frame’.

• Additionally, if suitable evidenced number of panes, U values, T solar or L solar values are available,then these should also be utilised.

• Automatic daylight zoning will apply.

• Each sun pipe should be modelled as a roof light as above, with the area equivalent to the crosssectional area of the light pipe in a horizontal plane, e.g. the area of the circular opening for circularpipes.