ASHRAE 90.1 lighting control question

5 posts / 0 new
Last post

Hello everyone,

A quick question regarding ASHRAE 90.1-2007 lighting control requirements (as I typically model buildings in Canada, and am not used to referencing ASHRAE 90.1).

Appendix G references section 9.4.1 for control, which states that automatic controls (e.g. occupancy sensors) are required in certain classrooms, conference/meeting rooms and lunch/break rooms. Does this mean that I will need to model the appropriate LPD reduction factor per Table G3.2 in these spaces in the reference building, as well as the proposed model (if they are installed)? I.e., no credit given? 90.1-2010 seems to expand on this, identifying occupant sensors specifically, and adding restrooms, small offices, lockers rooms and some storage room.

Do I have this right?

Thanks,

Adam Barker, C.E.T., LEED AP BD+C

AdamB's picture
Offline
Joined: 2011-12-22
Reputation: 0

Your interpretation is correct.

Thanks,

Sunayana Jain

Sunayana Jain2's picture
Offline
Joined: 2013-04-19
Reputation: 0

In spirit we're on the same page, but in practice I've come to approach this slightly differently:

I do not touch the Baseline model at all in regards to classrooms, breakrooms, and conference/meeting rooms. Rather, I understand that the fractional lighting schedule used in both models is taken to represent the prescriptively required sensors (there's language in Table G3.1 along these lines), and in turn I simply do not allow for an LPD reduction for those spaces in the Proposed model.

I expect the two approaches probably do not have a meaningfully different end-result for most projects, but can anecdotally affirm the above approach has made it through several LEED reviews.

Regards,

NICK CATON, P.E.

Nick-Caton's picture
Offline
Joined: 2011-09-30
Reputation: 605

x2
(What Nick said.)

William Bishop, PE, BEMP, LEED AP

Bill Bishop's picture
Offline
Joined: 2012-02-25
Reputation: 7

Thanks everyone, for the confirmation.

Adam Barker, C.E.T., LEED AP BD+C

AdamB's picture
Offline
Joined: 2011-12-22
Reputation: 0