Daylighting for perimeter zones or all?

Junaid Mujahid

Junior HVAC Design Engineer - Sustainability

PNC Architects

LEEDuser Basic Member

2 thumbs up

September 27, 2024

Hi,

Internal zones which do not have any external facades nor any windows are required to be simulated for Option 2: Illuminance? I have several zones which are considered regularly occupied zones but do not have any external windows/glazing.

A walk-around I can think of is to model the doors of these spaces as openings/holes to adjacent spaces which are perimeter zones. This way daylight would enter the space through the opening. Is this a valid methodology for simulating internal zones?

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Collin Robinson

The Sheward Partnership

LEEDuser Premium Member

0 thumbs up

Fri, 09/27/2024 - 14:39

I don't think it's valid to remove doors altogether. Often the doors are glazed in my projects, if not full glass partition. In that case, model single clear glass Tvis ~88% for interior glazing. It's rare to see much SDA in this situation, however. Since you are relying on reflectance of floor, be sure that's accurate. Start with LM-83 default 20% reflectance. If the flooring material is higher, such as grey resilient flooring, get that data from manufacturer or measure yourself. Ditto for ceiling reflectance.

Junaid Mujahid

Junior HVAC Design Engineer - Sustainability

PNC Architects

LEEDuser Basic Member

2 thumbs up

Mon, 09/30/2024 - 05:26

All interior doors in my project are opaque. Can they not be considered as openings/holes?

If not, then the illuminance values for these spaces must be considered 0 for LEED v4.1 Daylight Credit Option 2?

Elliot Glassman

Building Performance Group Leader and Vice President

CannonDesign

LEEDuser Basic Member

4 thumbs up

Mon, 09/30/2024 - 05:56

All doors must be simulated as closed. If they are opaque, no light gets through. If they are glazed, some light can pass through.