Is a parking canopy a "building"

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Carultch

Senior Member
Location
Massachusetts
Regarding 690.12 and rapid shutdown on "buildings", does a parking canopy count as a "building"? I don't believe it does, but how would I convince a skeptic that it isn't?
 

iwire

Moderator
Staff member
Location
Massachusetts
If you were a firefighter would you still want rapid shutdown available if say a car burns under the structure?

I think you would have an uphill battle to try to get an inspection department on board with not providing it.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Article 100 has a definition:

2011 NEC Article 100 said:
Building. A structure that stands alone or that is cut off from adjoining structures by fire walls with all openings therein protected by approved fire doors.

That definition seems overly broad, as it make any stand alone structure a building.

Cheers, Wayne
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
It is intended to be. If you think that is broad, see the definition of structure.
Sure, I'm familiar with that. But it seems like the definition of building usually just reduces to that of structure, which isn't so useful.

For example, take the OP's concern with (2014) 690.12 Rapid Shutdown of PV Systems on Buildings. Unless you are laying your PV panels down on the ground, they are going to be mounted on a structure, and hence a building. So 690.12 applies even to a PV system mounted on a pole in the middle of a field. Of course, 690.12(1) exempts the wiring on this pole mounted array, unless your "PV system conductors" travel more than 5' inside the building (pole).

But I don't think most people reading 690.12 would think that the requirements could apply to a pole mounted array in the middle of a field; they would say that is not a building. The NEC definition says otherwise.

Cheers, Wayne

P.S. What are "PV system conductors"? That term is not defined in 690. Is it intended as shorthand for "PV Source Circuit" conductors or "PV Output Circuit" conductors? I.e. all PV-supplied DC conductors?
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
IIRC, in California carport structures longer than a certain size (150', maybe) must have firewalls and sprinkler systems installed.
 

pv_n00b

Senior Member
Location
CA, USA
The NEC definition is:

Building. A structure that stands alone or that is cut off from adjoining structures by fire walls with all openings therein protected by approved fire doors.

Structure. That which is built or constructed.

Now we get to the logic statement that all buildings are structures but not all structures are buildings. So what sets a building apart from other structures? There is little that specifically defines it that I have seen, there are "industry practices" that define a building as having walls. I've specified a lot of central inverter shade structures as open structures with only a roof so the civil engineer did not have to make them meet the requirements of a building in the IBC. It becomes one of those things where 99% of the AHJs accept X and 1% define it some other way. You can try to convert the 1% AHJs to everyone else's way of thinking, give them what they want, or don't do projects in their area.

There is the intent of RSS also, it is intended for enclosed buildings, not freestanding frameworks or ground mounted PV arrays.
 

SolarPro

Senior Member
Location
Austin, TX
Bill Brooks says as much in his trainings. (He's not only a member of CMP4, but also headed up the task force that first drafted 690.12.) In inspector and installer trainings, Bill's stock example of a common PV scenario that is not subject to 690.12 is a ground-mounted PV system where the PV system conductors do not touch or enter a building.

Here's an excerpt from a SolarPro article Bill has written on this subject [emphasis added]:

Understanding Rapid Shutdown

Since the Code language is an installation requirement and not an instruction manual, here I address some of the frequently asked questions regarding rapid shutdown.

Which systems must comply?
As stated in the section title, rapid-shutdown requirements apply to PV systems on buildings. If you are installing a roof-mounted PV system subject to NEC 2014, the rapid-shutdown requirements clearly apply to your project. If you are installing a ground-mounted or similar system where none of the PV system components or circuits contacts a building, the rapid-shutdown requirements do not apply.

This does not mean that all ground-mounted PV systems are exempt from rapid-shutdown requirements. Where PV system circuits from a ground-mounted PV system are physically attached to or penetrate a building, you should apply NEC 690.12. However, in this case, the conductors on or entering the building are subject to rapid shutdown, but the conductors off the building are not. Note that underground conductors that travel under buildings are not considered to be “on or in buildings.” Where buried conductors come up into a building, you are allowed to run them a distance of 5 feet from the point of penetration through the floor before installing a disconnecting means.

The comments and substantiations associated with 690.12 are all public record. The intent is clear if you read these or simply read Bill's articles. Here's another article on the topic published by the IAEI:

Rapid Shutdown of PV Systems
 
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iwire

Moderator
Staff member
Location
Massachusetts
I am not really interested in people's opinions of intent regardless of who they might be. I am well aware the CMPs actions are public and if I was that curios I would look at them. :)
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
The NEC definition is:

Building. A structure that stands alone or that is cut off from adjoining structures by fire walls with all openings therein protected by approved fire doors.

Structure. That which is built or constructed.

Now we get to the logic statement that all buildings are structures but not all structures are buildings.
Sorry, the definition of Building in the NEC is so broad that logically, every structure consists of one or more buildings.

If that is not the intent, the definition requires updating.

Cheers, Wayne
 

SolarPro

Senior Member
Location
Austin, TX
I am not really interested in people's opinions of intent regardless of who they might be. I am well aware the CMPs actions are public and if I was that curios I would look at them. :)

Right. Because the original intent of the authors is obviously irrelevant to the application of the code in the real world. Whatever you think it means is what it must mean. :roll:
 

SolarPro

Senior Member
Location
Austin, TX
Sorry, the definition of Building in the NEC is so broad that logically, every structure consists of one or more buildings.

If that is not the intent, the definition requires updating.

Cheers, Wayne

You code purists probably don't believe in the explanatory notes in the NEC Handbook either. But these provide multiple illustrations of PV array support structures. And the text itself differentiates betweens buildings and structures. So common sense, context, explanatory text, substantiating comments and subject matter expert testimony all point to the fact that structure ≠ building.

Rapid shutdown applies to PV systems on buildings. If it applied to PV systems on structures, it would apply to all PV systems. See the definition of an "array" of Article 690.

If 690.12 applies to all PV systems, why do you think the CMP added the words "on buildings" to the title?
 

Carultch

Senior Member
Location
Massachusetts
You code purists probably don't believe in the explanatory notes in the NEC Handbook either. But these provide multiple illustrations of PV array support structures. And the text itself differentiates betweens buildings and structures. So common sense, context, explanatory text, substantiating comments and subject matter expert testimony all point to the fact that structure ≠ building.

Rapid shutdown applies to PV systems on buildings. If it applied to PV systems on structures, it would apply to all PV systems. See the definition of an "array" of Article 690.

If 690.12 applies to all PV systems, why do you think the CMP added the words "on buildings" to the title?

Maybe they intended for it not to apply to a PV array that is magnetically levitated, or the new concept of "floatovoltaics". :lol: Because I can't think of any other kind of PV array that isn't mounted on anything that could be called a structure.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Right. Because the original intent of the authors is obviously irrelevant to the application of the code in the real world.
In the event that ambiguous language has been adopted, the intent of the authors is useful in clarifying it, I would say.

But if the authors intend to say A but the plain meaning of the words chosen is B, the authors' intent can't magically redefine words.

Most likely, the authors of 690.12 weren't aware of the breadth of the Article 100 definition of building.

Cheers, Wayne
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
Let's back up and ask a substantive question:

Is there an important justification for having rapid shutdown one a parking lot solar canopy structure? Or not?
 

Smart $

Esteemed Member
Location
Ohio
Let's back up and ask a substantive question:

Is there an important justification for having rapid shutdown one a parking lot solar canopy structure? Or not?
What's the justification for having an RSS? I'm pretty certain code does not provide one. Code just requires there to be one under certain conditions. We can debate the conditions but not the justification IMO.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
What's the justification for having an RSS? I'm pretty certain code does not provide one. Code just requires there to be one under certain conditions. We can debate the conditions but not the justification IMO.

We are not limited from debating what the code should say.
 

Smart $

Esteemed Member
Location
Ohio
We are not limited from debating what the code should say.
That is quite true, and I did not mean to imply otherwise... just meant delving into justification will certainly not resolve whether a parking canopy is a building or not.

If you ask me, if the canopy is capable of supporting a PV System of any substantial size, it is a building. What I would call a stand-alone parking canopy for a passenger car or two are not capable of supporting a PV array covering most of the canopy's surface area.
 
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