My core and shell building is over 400K SF. The majority of which is tenant space that is NOT fit out. There is no way of knowing a typical layout given the large, varying floor plate. What has GBCI approved in terms of approach for daylighting? Do they require that you daylight in baseline and proposed for perimeter spaces? Have they defined different parameters for space that are not fit out? Do they allow daylighting to be excluded? If the project is claiming lighting savings use BA method, does this change their review of daylighting ? Please advise.
If you are not claiming any savings related to the tenant lighting you model the lighting power density identically and don't model the daylighting controls in the baseline. This is a conservative approach. The alternative would require that you develop a typical layout for the tenant spaces and apply daylighting controls to both models since this is a mandatory provision. The later strikes me as busy work for no real effect on savings but technically it is probably how it should be addressed.
If you are claiming savings for tenant lighting through a lease agreement then I think you should be required to model the baseline daylighting controls based on a typical layout.
I am following up on a previous comment regarding daylighting for Core and Shell space that is not fit out.
Lorey Flick
PartnerFlick Engineering Professionals
38 thumbs up
June 12, 2019 - 10:46 am
Please disregard the last 3 paragraphs- I copied from a previous forum as I wrote my question...Another question- How do you edit after you post??
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
June 12, 2019 - 2:43 pm
In v4 daylighting for the perimeter spaces is required by 90.1-2010.
No daylight can't be excluded from spaces where it is required. If you wish to claim savings for daylighting in tenant spaces you will need to have a signed lease agreement for those spaces and you will need a floor plan showing the layout of the spaces. If a space is not going to be fitted out then you cannot claim savings. Either LPD method could be used.
Lorey Flick
PartnerFlick Engineering Professionals
38 thumbs up
June 14, 2019 - 2:17 am
Thanks Marcus. Please confirm that I will need to model daylighting in the perimeter zones (as defined by ashrae zoning of undesigned spaces) identically in the baseline and proposed cases. If I am making envelope changes that will certainly impact the daylighting energy numbers, how am I to avoid claiming savings if I am required to model the undesigned spaces with daylighting?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
June 18, 2019 - 3:46 pm
You model the baseline and proposed identically if there is no proposed design. If their is a proposed design then you model the proposed as designed.
How will the envelop changes affect the daylighting savings?
Lorey Flick
PartnerFlick Engineering Professionals
38 thumbs up
June 18, 2019 - 4:32 pm
Glazing properties have a direct impact on available daylighting. My building has an existing tint/coating and we are looking at replacing glazing and/or tint.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
June 18, 2019 - 5:42 pm
Those savings would be related to the glazing choice, so they should be acceptable. Modeled identically does not mean that you get exactly the same energy use for lighting. This happens from time to time when applying the model identically rule.