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Origin of California Building Code PV Panels Over Parking Stalls Exception

N

NFPAnarc

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Arlington, VA
Does anyone know the origin or development of the CBC Section 503.1 Exception 3 language? To my knowledge there is no commentary language to state amended versions of the IBC, but I'm curious how they determined the maximum array coverage area and separations. When used in conjunction with 903.1.1.3 it seems like you could sort of create a partially covered parking lot without requiring sprinkler protection or creating an open parking garage.
 
NFPAnarc said:
thats entirely possible, I couldn't find anything to suggest where they got the requirements from though, kind of seems arbitrary
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Yep...they want solar and they want it to have special treatment to be cheaper so they can make more money..

Of course you sprinkler a 500sqft S1 when you have batteries.....In 2024 IBC:

1722281754369.png
But maybe they will call it a canopy and not a building.....Starting to sense a theme.....
 
EXCEPTION #3
Other than structural requirements, solar photovoltaic panels supported by a structure over parking stalls shall not constitute additional story or additional floor area and may exceed the height limit as specified in exception 2 (above) when the following conditions are met (see Figure 5-1):


Seems to be specifically applicable to the upper level of a parking structure.
 
I agree but but there is no requirement in the exception language that it has to be on top of a parking garage, just "over parking stalls," which could be applied to grade level parking.
 
NFPAnarc said:
I'm curious how they determined the maximum array coverage area and separations.
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Committee. It is alway the consensus of a committee.

NFPAnarc said:
I agree but but there is no requirement in the exception language that it has to be on top of a parking garage, just "over parking stalls," which could be applied to grade level parking.
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I do not have 903.1.1.3 and I assume the section creates a negative issue. Perhaps you can provide a copy of the section?
 
503.1 exception 3 did not appear in the 2010 CBC, copied below:

1722290925869.png

It showed up in the 2013 CBC as 503.1 exception #2, with double lines next to it indicating recent modification:
1722290093234.png

It was part of a package of changes to encourage PV installation, summarized here:
1722290553348.png
 
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I'm willing to bet that was derived from the assumption that if its S-1 its a repair garage, and an EV in need of "repair" could be a higher fire risk. S-2 parking garages assume operational vehicles that are "road worthy" and less of a fire risk. 500 sqft is probably about 3 or 4 repair bays, which would cover most commercial repair garages or dealership maintenance areas.
 
NFPAnarc said:
I'm willing to bet that was derived from the assumption that if its S-1 its a repair garage, and an EV in need of "repair" could be a higher fire risk. S-2 parking garages assume operational vehicles that are "road worthy" and less of a fire risk. 500 sqft is probably about 3 or 4 repair bays, which would cover most commercial repair garages or dealership maintenance areas.
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No car repair place is messing with those batteries....Not that the sprinkler system is going to do much in a Lithium battery fire anyway....Someone is being thrown a bone and it is the EV/parking industry....
 
NFPAnarc said:
So it seems like it was all derived to push solar with less impact on new buildings
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I’ve seen it utilized very often on retrofitting existing apartments and offices:
- putting solar PV on flat roofs without having to recalculate allowable height/area.
- creating solar ‘carports’ without having to justify allowable area, imaginary property lines, and the effect of carport PV structures on allowable % of wall openings on adjacent existing apartments.
 
I recall a case where a planning dept refused an application for a patio cover over a single story garage due to proximity to the PL. The owner invoked a state mandate that prevents an AHJ from denying solar arrays due to proximity to a PL. Of course a structure to support the solar is required and that structure happened to be a patio cover.
I bring this as an example of creative use of codes and laws.
 
ICE said:
I recall a case where a planning dept refused an application for a patio cover over a single story garage due to proximity to the PL. The owner invoked a state mandate that prevents an AHJ from denying solar arrays due to proximity to a PL. Of course a structure to support the solar is required and that structure happened to be a patio cover.
I bring this as an example of creative use of codes and laws.
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I like it!

I note that on DSA projects (such as public schools), the solar array itself does not have to be accessible, but if it also happens to be used for another purpose - - for example, if there is educational signage explaining how the solar PV is part of a sustainable future - - that educational experience needs to be accessible.
 
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