We are simulating Airport Traffic Controller building and have question regarding baseline system.
Building is 13 story and have 27,000 sf. However, out of 13 floors, only 3 floors have conditional spaces. Other floors are mechanical and electrical spaces. Also, out of 27,000 sf, only 2,500 sf are regularly occupied spaces. Therefore, our building has 3 story and less than 25,000 sf regular occupied space. Table G3.1.1A does not clearly indicate whether to use gross area or net area, or conditional space or all the spaces to determine baseline system. I was wondering if we can use system 3 for baseline since our building has 3 story and less than 25,000 sf regularly occupied space.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
July 17, 2012 - 9:30 am
You enter the table based on the conditioned floors and square footage. So a system 3 makes sense.
Hirak Patel
5 thumbs up
July 17, 2012 - 2:02 pm
Is there any reference in ASHRAE 90.1 or LEED?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
July 17, 2012 - 2:21 pm
I don't know off the top of my head. I took a quick look in Appendix G and did not see anything specific. You might look at the User's Manual to see if there is any further guidance there. It is not unusual to find a grey area that requires interpretation. If you need something official then you need to submit a formal interpretation.
Think of it this way. You have a three story office building with an attached parking garage. The scenario is the same as you have described it.
Steven Er
11 thumbs up
July 25, 2012 - 3:33 am
Hi,
ASHRAE 90.1 2007, Appendix G, G3.1.1 states "HVAC systems in the baseline building design shall be based on usage, number of floors, conditioned floor area, and heating source as specified in Table G3.1.1A....."
It clearly mentions that area taken for baseline HVAC system selection shall based on conditioned floor area. I assume it apply to number of floors. Any idea?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
July 25, 2012 - 4:23 pm
I agree that it would be the number of conditioned floors.
Francesco Passerini
engineer90 thumbs up
February 12, 2014 - 10:12 am
Three floors of the building that I'm modeling are almost completely conditioned, while another floor is underground and has 27 m^2 of conditioned area and about 1200 m^2 of unconditioned area, i.e. for the underground floor the conditioned area is about 2%. For the selection of the baseline system (Table G3.1.1A), shall I consider 3 or 4 floors?
Regards
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
February 12, 2014 - 10:30 am
Technically it is 4 floors. Is the total conditioned area under the total allowed for a system 3/4? Do you anticipate any G3.1.1 exceptions?
Francesco Passerini
engineer90 thumbs up
February 12, 2014 - 11:41 am
I recalculated the conditioned floor area: it is 2909 m^2, therefore I shall model system 6. In a first time I estimated a lower value... Thank you.