Hello Marcus Sheffer,
Refering to the LEED Interpretation 10371 related to taking credit for DCV in car parks, it is specified:
1) that the proposed case should be modeled such as that a minimum air flow of 0,05 cfm/ft2 should be maintained;
2) that car park ventilation rate and fan power in the baseline building shall be modeled as 0,75 cfm/ft2 and 0,3 W/cfm, respectively.
Can you please tell me the source of the following numbers:
a) 0,05 cfm/ft2 as minimum exhaust rates for the proposed building;
b) 0,3 W/cfm for the fanpower in the baseline building
Thank you in advance,
Best regards,
Pedro Ribeiro
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5925 thumbs up
August 16, 2016 - 12:46 pm
a. We think the 0.05 comes from the International Mechanical Code 2009 minimum Section 404.2.
b. The 0.3 probably comes from the fan power requirements for system 9/10 in 90.1-2010 but we are not sure.
Ricardo Sá
Director of SustainabilityEdifícios Saudáveis Consultores (503 910 767)
86 thumbs up
August 18, 2016 - 10:32 am
Thank you for your response, Marcus!
I still have a few questions regarding this matter:
a) Can I claim savings with the DCV for car parks ventilation, even though there is a portuguese law (where the project is located) that requires this DCV? (meaning that this is standard practice);
b) If not, and since this DCV is standard practice, how do I model the Baseline case? As per ASHRAE 90.1 - 2010? Or as designed?
c) If it is as designed, am I right to assume this as process load, since it is not regulated under ASHRAE 90.1 - 2007?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5925 thumbs up
August 19, 2016 - 12:05 pm
a. No. If it required by local code then that is the baseline in that area.
b. Identical to the design.
c. Yes it is a process load