hello,?
? ? ? ? ?Does anyone know if we can use building area method for lighting in the proposed case for a LEED App G simulation. We were just given the total wattage of the building from the lighting designer. Or would we have to go through the lighting layout and calculate the power for each zone.
thanks
raj
Kris,
Refer ASHRAE 90.1-2007 Appendix G Table G3.1 item 6 for the Proposed
Building Performance.
Yes, you have to go through the lighting layout and calculate the power for
each zone.
Robby Oylear, P.E., LEED AP
Robby, Thanks for your response. I did see that section. It just gets confusing because the same section seems to indicate that the baseline lighting power density can be based on whole building method. Also the LEED EAp2 1.4 template excel spreadsheet has entries to indicate weather the lighting is based on space-by-space or building area method.
thanks
raj
Kris,
There was a detail discussion on the same issue few weeks before on eQuest
forum. you can check the archives by following key word:
"Building area method ASHRAE 90.1"
Hope you will get all your doubts clear there!
Thanks!
Javed is right - that discussion on [Equest-users] pretty much covered all angles of this topic - recommended reading! Following is an additional response I threw together for Robby/Kris that I think nails down some grey areas:
I may be reading the question differently, but I would add the space-by-space method is not a requirement. It's usually a good idea from a "I want to get more LEED points perspective," as the space-by-space approach often yields a higher allowable LPD overall, but one can choose to model the proposed and baseline either using the building area or space-by-space approach. Do not however mix your approaches between the models.
This point (being able to use either method to tally/model LPD) is pretty explicitly made in the same cited Table G3.1 section under the Baseline requirements.
If the lighting designer has calculated the installed LPD, nothing in the standard dictates the modeler must perform separate takeoffs ... but expect to shoulder blame if those calculations do not satisfy the reviewers. From personal experience, I advise against placing a heavy amount of trust in others' LPD calcs. Energy models are only ever as strong as the weakest inputs used to build them.
NICK CATON, P.E.
Dear colleagues,
I was wondering if you know of a template detailing indicative tasks and resources required to guide the "as construction" certification process for a 20,000m2 project (i.e. certification management), assuming that the contractor has never build an environmentally certified building before.
Any help will be greatly appreciated
Thanks in advance
Ioannis
Nick is right you can use the BAM in the proposed design if you choose. However the challenge i have found with that approach is you may end up with thermal zones that have higher LPD then actually installed which may lead to high unmet cooling hours.
Philosophically I'm not a fan of using BAM because it's too easy to move lighting power from high LPD areas with few burn hours to low LPD areas with high burn hours which artificially inflates the baseline. This is part of the reason you can't mix BAM and SBS methods.
Michael Tillou