Working on a project where the wall sconce will be installed under the building's overhang and canopy. This will not light up the sky.
Is there a specific way of calculating the reduced (or completely eliminate) the lumens above horizontal based on the roof overhang? Trying to see if I can reduce this in order to meet the requirements under the calculation method (1.5% in LZ2)
Any help would be appreciated!
Bill Swanson
Sr. Electrical EngineerIntegrated Design Solutions
LEEDuser Expert
735 thumbs up
February 26, 2021 - 10:02 am
Draw a section showing the light and the overhang. What is the angle from the light to this overhang? 0 deg being straight down and 180 deg being straight up.
Insert the IES file into a program that will tell you how much light is emited in each 10 deg range. Second page, "Lumen per Zone"
https://www.visual-3d.com/tools/photometricviewer/
Making some assumptions, the overhang edge is at about 140 deg from the light. Any light emitted between 90-140 deg is still uplight that gets counted. All of the light from 0-90 deg is downlight and the light from 140-180 deg is shielded by structure.