Hi All,
Kindly clarify baseline LPD to be used for multi-family residential spaces (living room, bed room, kitchen, rest room, etc) as per ASHRAE 90.1-2010. The light fixtures along with luminaires inside the dwelling units will be installed by developer.
1. The baseline LPD for residential spaces is not mentioned in space-by-space method. But as per ASHRAE 90.1-2010 Table G3.1.1.C, where the space classification for a space is not known, the space shall be categorized as an office space. So, for dwelling unit, can we consider baseline LPD as 1.11 W/ft2.
2. The building area method mentions the baseline LPD for multifamily residential building as 0.6 W/ft2.
Kindly suggest the right approach to consider the baseline LPDs as we are planning to propose an ECM of LPD reduction in those spaces below these baselines to get savings.
Thanks in advance.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
August 22, 2017 - 9:38 am
1. This is a misinterpretation. Table G3.1.1c only applies to spaces where you don't know what it will be used for in the future. In your case you know the space type, it is just not covered by the space-by-space list of space type.
2. That is one option.
See LEED Interpretaion 5253 for specific guidance. The Energy Star Multifamily High Rise Program Simulation Guidelines (Version 1.0, Revision 1, June 2, 2012) are an acceptable methodology for documenting savings for space lighting within the dwelling units.
F. Borja López Calle
ConsultantMinsait
2 thumbs up
January 16, 2018 - 11:19 am
Hi,
Although I agree with the answer given by Marcus to option 1, I don't think the 2nd is an option since ASHRAE G3.1.6 states that "for multifamily dwelling units you should assume identical LPD for the proposed and baseline building designs in the simulations". Furthermore, the LEED Interpretation 5253 states that only common areas and support spaces should be modeled as 0.7 W/sf.
On another note, what I find unclear is what should be considered as process energy and what shouldn't. According to the Interpretation "all hard- wired lighting in living units that is shown on the building plans" shall be considered process energy. So, would this case be considered process energy? Or only is you install the light fixtures and not the luminaires?
Thanks in advance.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
January 18, 2018 - 9:54 am
Regarding option 2 above - the building area method is an option for multi-family residential. You are correct that savings could only be applied to the non-dwelling unit areas but you could model the dwelling units with 0.7 W/sf identically and this would be acceptable to the reviewer. Given the fact that 90.1 does not set a baseline for dwelling unit in multi-family residential, USGBC has allowed projects to model this several different ways.
Process energy is any energy use associated with the building that is not regulated by 90.1. So dwelling units in multi-family residential are not regulated (there is no baseline) and are therefore process energy.