Hi,
By following the Multifamily Energy Model Simulation Guidelines, lighting in dwelling unit spaces shall be modeled as lit for 2-3 hours per day; so, we distributed these hours throughout the day, but mostly during early morning and late night. Since so few hours per day are modeled and mostly during low natural light availability, the daylight sensors do not provide any reasonable savings considering that this project is in a country where the sun rises and sets roughly from 6am to 6pm year-round.
One of the spaces within the dwelling units does exceed the threshold of 250ft2 for primary sidelighted area, so it would fall under the mandatory provision requirement. Is there any workaround for this requirement when savings are insignificant? The proposed lighting power density for hard-wired lighting in this family room is 0.29 W/ft2, which would further contribute to very low energy savings.
Thanks! Looking forward to your response.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5911 thumbs up
October 26, 2021 - 1:23 pm
Since the lighting in residential units is not regulated by 90.1, hence the need to use the Multifamily Guidelines, I would think that the mandatory provisions do not apply. They only apply to the regulated lighting loads.
Gaston Michaud
Mechanical EngineerENEX
14 thumbs up
October 26, 2021 - 1:39 pm
Thank you Marcus, I agree. Do you think the LEED Reviewer would accept this explanation? This is actually one of his comments.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5911 thumbs up
October 26, 2021 - 2:00 pm
I think so. As a reviewer I certainlyu would.