Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
About the 34' high gym ceiling...I think you might want to avoid using thumb rules on that one, instead a short conversation with the lighting designer if possible. Do the windows start at floor level, or at least at low sill height? Or are they clerestory windows, with sill height of 15'? If the windows are placed high up, then the area near the wall will get less natural light most of the year, and the daylighting zone will get pushed inwards, like an island. Those type of questions will help distill the daylighting zone modeling criteria for you.
Also, about the ceiling height based daylighting zone depth...that thumb rule considers the possibility of considerable light first being reflected on to the ceiling, which then can be re-reflected into deeper space. Thus, check whether you have light shelves, or other daylight redirection devices in place, or the exterior ground being very reflective (then you gotta think about direct glare as well btw) etc.
For a good primer on daylighting thumb rules: http://www.gsd.harvard.edu/research/gsdsquare/Publications/DiffuseDaylightingDesignSequenceTutorial.pdf
Hope this helps.
| | 2 | No.2 Revision |
About the 34' high gym ceiling...I think you might want to avoid using thumb rules on that one, instead a short conversation with the lighting designer if possible. Do the windows start at floor level, or at least at low sill height? Or are they clerestory windows, with sill height of 15'? If the windows are placed high up, then the area near the wall will get less natural light most of the year, and the daylighting zone will get pushed inwards, like an island. Those type of questions will help distill the daylighting zone modeling criteria for you.
Also, about the ceiling height based daylighting zone depth...that thumb rule considers the possibility of considerable light first being reflected on to the ceiling, which then can be re-reflected into deeper space. Thus, check whether you have light shelves, or other daylight redirection devices in place, or the exterior ground being very reflective (then you gotta think about direct glare as well btw) etc.
For a good primer on daylighting thumb rules:
http://www.gsd.harvard.edu/research/gsdsquare/Publications/DiffuseDaylightingDesignSequenceTutorial.pdfrules, see this 2009 Harvard presentation 'Daylighting, Rules of thumb'.
Hope this helps.
