IES-VE User Forum

Hi,

I was just wandering why IES allows a diversity to be applied to the actual building's lighting.

My understanding is that the actual and notional building should share the same lighting profile so a comparison can be made on a like for like basis.
Hence in VE compliance the lighting profile cant be changed.

On what grounds can you justify altering the lighting diversity? Can this be changed if there is any intention to run the lighting for a limited time only?

It seems a bit of a contradiction that the lighting profile is set in stone but the diversity isn't.

Ross

If IES allows you to change the actual building lighting diversity within VE Compliance then I'd say that's something that needs plugging asap because it would not be in line with the NCM modelling guide.

That said, VE Compliance is simply a tool to help automate the process described by the NCM Guide but ultimate responsibility for ensuring that the models are in line with said guidance is in the hands of the modeller/assessor, not the software vendor. Afterall, you can use any compliant dynamic software to do a Part L assessment, some of which have no NCM automation at all.

Hi,

I agree, Clause 165 of the modelling guide states:

The database provides standard occupancy, temperature set-points, outdoor air rates and heat gain profiles for each type of space in the buildings, so that buildings with the same mix of activities will differ only in terms of their geometry, construction, building services and weather location. Thus it is possible for the Building Regulations Regulation 17C compliance test and EPCs to compare buildings on their intrinsic potential performance, regardless of how they may actually be used in practice.

Adjusting the diversity on the lighting would not be comparing the actual and notional buildings on their 'intrinsic potential performance'.

Thanks

Ross