In the CI reference manual the calculation for Daylight factor is as follows:
Daylight Factor = (Window area/floor area) x Window Geometry x (Actual Tvis/Min Tvis) x Window Height Factor.
Can someone enlighten me as to how to find the "Actual Tvis" of our glazing?
many thanks.
alex
Tristan Roberts
RepresentativeVermont House of Representatives
LEEDuser Expert
11478 thumbs up
January 12, 2010 - 5:09 pm
Tvis is the same as "visible light transmittance" or simply "visible transmittance" and should be found in your glazing specifications or cut sheets. It's a standard measurement—not something you should have to guess at.
Does that help?