I hope everybody is having a great day! I came across this thread and a bunch of questions popped into my head. (Well, I´m new to the energy modeling business, so I always have questions I guess)
In my case, I´m modeling a building 7 stories tall with a 4 level basement for parking. This is an office building. Nevertheless, I wonder if Standard 90.1 (Table 9.5.1) contemplates the idea of having parking lots for an office building. That is, does it mean that the 1.0 value of LPD listed there considers a building made up of office spaces only?. Im inclined to use Building Area Method because this is a C&S project.(lighting layout is already defined all spaces, but we don´t know if tenants are going to stick to the type of luminaries that were recommended)
[another question] Following up on the previous one: ´´does it mean that the 1.0 value of LPD listed there considers a building made up of office spaces only?´´ If the answer is yes, then how should I go about finding the LPD value for my project? (baseline building)
[another question] As far I understand, Standard 90.1 is meant to be used to come up with the baseline building (among other goals). However, if we want to get more points for EA credit 1, one of the things we could do is reduce the energy consumption due to lighting systems. In that sense, we may have some type of luminaries that reduce the energy consumption, but at the same time yield a smaller value of LPD. Consequently, this new value of LPD is the one that must be accounted for in the proposed building simulation. That being said, how do I find the new LPD value for my proposed building case. Recall that I´d like to use the Building Area Method. (Sorry, no data of LPD can be found in the design documents. Long story)
Thank you all for your time!
Alex
0 51. 991411862
PS: If you would like to share any files that may help me out with this, please email them at aatahua@ibridsac.com
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5868 thumbs up
September 20, 2012 - 10:14 am
You should use the 1.0 for the office area and the 0.3 for the parking garage listed in the same table. Yes the 1.0 is typically for office spaces only. If there are other space types use the BAM values for those.
You will need to be able to document the LPD in the proposed. This must be based on the design and/or required LPD values for tenants in the lease agreement. Without either one you cannot claim any lighting savings. Applying the BAM in the proposed would be to add up the total watts of lighting designed and required and dividing by the total square footage and then using this value in each zone in the model.
Alex AC
6 thumbs up
September 20, 2012 - 10:49 am
Thank you Marcus! I really appreciate your quick response. Nevertheless, I want to make sure I got this straight. So, since I have both parking and office spaces in my building, the way I would calculate the LPD using BAM method for the Baseline Building case is: (0.3*A1 + 1.0 A2)/(A1 + A2)
Where A1 and A2 are the square footage of the parking spaces and office spaces respectively.
And, in the case of the Proposed Building, I simply add up the total watts of lighting designed/required and divided by the total square footage to calculate the LPD.
Right?
Thanks again!
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5868 thumbs up
September 20, 2012 - 11:27 am
That would give you the overall weighted average but that is not how you model it. Simply enter 1.0 in each zone in the model for the office space and 0.3 in each zone for the parking garage in the baseline. Do the same thing for the Proposed. Add up the office lighting wattage and divide by the office square footage and use that value in all the office zones. Do the same for the garage. So treat the spaces separately not with an overall weighted average.
Alex AC
6 thumbs up
September 20, 2012 - 12:03 pm
I see. It´s all clear now. Glad to have you as a member of this forum. Have a nice day!
mmmm Now that I´m taking a closer look at the LEED reference guide for green building design and construction (LEED2009-BD + C) [Page 271], it seems that we cannot use BAM method for the case of C&S after all. Am I right or am I missinterpreting it?
THANK YOU!
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5868 thumbs up
September 25, 2012 - 3:34 pm
The BAM is far more appropriate for C&S projects in many cases than the the SBSM, especially for open spaces that have not been designed. The baseline guidance in the Reference Guide (use the SBSM only) makes no sense. The Proposed guidance is very confusing stating that the LPD should be calculated "according to the building area method using appropriate space type classification from Table 9.6.1" (SBSM). This mentions both methods.
Despite the confusion in the RG it is my understanding that you can use the BAM for C&S projects. In fact I would argue that it is more appropriate to use BAM in C&S projects than in other project types with a more complete design.