# PV module location on flat roof



## earshavewalls (Dec 1, 2010)

I have a bit of a dilemna. Per the California Building Code, Section 1013.5, any equipment that requires service that is installed within 10' of a roof edge is required to have guards (or parapet) at 42" above the roof surface to extend 30" beyond each end of the equipment.

This has not been an issue until now. A contractor is wanting to install a relatively small PV system on a commercial building with extremely low parapet walls. The only setback they recognize is the Fire Department's requirement for all panels and equipment to be min. 48" from the roof edge. So, this is how close they propose to install their panels. They are attempting to claim that photovoltaic panels never require any service, and therefore they are exempt from this requirement. I do not believe in absolutes, myself, so their claim of panels NEVER requiring any service is not making it into my brain.

I believe this is a life-safety issue and that the module layout needs to comply with this requirement. The designer/contractor is claiming that they cannot reconfigure and that if they cannot install this system as shown, the project will not be done. Well, I'm not buying it.

Has anyone else come across this sort of thing? The biggest problem here is that it is a very small building, and that the building is a "commercial condominium" where each space is "owned" by the tenant. There is also a parapet between the units, but this parapet is not at issue. I believe this is a case of trying to fit more than is possible on an existing building. We have several large PV installations on J.C. Penney, 2 Kohl's, and another at our own, City-owned facility. ALL of these systems met this requirement from the beginning.

Now I'll take all the flack from this group......lol.

Have any of you who are in enforcement run into this argument?

Thanks


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## fatboy (Dec 1, 2010)

We have not enforced the equipment guards on PV arrays, and we've had quite a few, both commercial and residential. I don't buy that they won't ever need repair or replacement, but I don't see that you would be "servicing" them frequently enough to justify guards. JMHO


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## earshavewalls (Dec 1, 2010)

I just had another PV installer come in to submit with a micro-inverter system. The main benefit for this type of system (micro-inverter) is that IF one module goes down, the other inverters "take up the slack" of the others. The key here is IF a module goes down. This system would not be able to make such a claim if PV modules didn't have issues where they may need to be replaced from time to time.

I feel that this is a safety issue. It does NOT apply to sloped roofs (residential, mostly), but it does apply to flat roofs. I know that there are systems being installed all over that do not recognize or just are not aware of this code requirement, but that does not change the fact that this is a safety issue aimed toward service personnel. It only takes one time for someone to slip and fall. The project I am reviewing may end up having problems with people being able to see the array from the ground, and may have them raise the parapet anyway...........like I said, this is the first time this has come up (probably won't be the last) on PV systems. I have also checked with a few manufacturers. They are VERY proud of their products and state that under perfect conditions, their modules MAY not require servicing for 20 years....but they would not come out and say that their modules would NEVER require servicing......I asked them......


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## fatboy (Dec 1, 2010)

So, why would it apply to a flat roof, and not a pitched roof?


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## Dr. J (Dec 1, 2010)

A PV panel itself requires no more service that a roof membrane (metal, shingle, EPDM, asphalt, etc).  Will a roof membrane require service?  Some fail 2 months after installation some last 20 years.  Do all roofs require fall protection just because they at some time require service?

You should look for more "mechanical" components such as disconnects or tracking mounts, these would require actual "service".  Also, in snow country consider flat vs sloped panels - someone may need to sweep snow off horizontal panels, but not sloped.

I encourage all AHJs to address this issue by written amendment/policy since you will be seing more of this, and it will take a while for the model codes to catch up.


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## TimNY (Dec 1, 2010)

PV panels *DO* require service.  Debris (such as leaves) need to be removed regularly.  I am told they lose a disproportionate amount of electricity when obstructed.  I watched a guy walk in 3 panels deep to remove a leaf.

Not familiar with CA building code (so not sure if it refers to "servicing" in the scope of the electrical chapter, or if "servicing" can be broadly interpreted), so YMMV.


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## Dr. J (Dec 2, 2010)

Debris is much less of an issue than snow, but I'll agree that if someone puts horizontal panels adjacent to and lower/level with large (or will be large) trees, this could be an issue, particularly if they were required to provide a parapet for fall protection that then traps leaves.  Bottom line, review with all these issues in mind, and apply fall protection requirements appropriately, but not with a blanket statement.


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## FyrBldgGuy (Dec 2, 2010)

View attachment 281


These are solar panels in a ground array.  Sometimes they need servicing.  And sometimes that doesn't happen often enough.  Then they burn.
	

		
			
		

		
	

View attachment 281


/monthly_2010_12/572953bb4edd3_SolarPanelsDamaged.jpg.c3be6bbcd7fe4ab5c9a3feff34ed60e6.jpg


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## David Henderson (Dec 6, 2010)

My understanding of the Micro Inverter, is to pick up the slack when one Module becomes shaded


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## Brookhaven 58 (Dec 8, 2010)

The first time I ran into this situation I too required the installation of guards at the roof edge (BCNYS 1012.5) but was informed by the regional rep from NY State that the PV panel were considered part of the roof ans guards were not required.

1012.5 Mechanical equipment. Guards shall be provided where appliances, equipment, fans or other components that require service are located within 10 feet (3048 mm) of a roof edge or open side of a walking surface and such edge or open side is located more than 30 inches (762 mm) above the floor,

roof or grade below. The guard shall be constructed so as to prevent thepassage of a 21-inch-diameter (533 mm) sphere.

In this configuration, leaves or snow drifts would not or should not be a problem.


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## Paul Sweet (Dec 8, 2010)

Could the PV panel itself be considered the guard if you can clean or otherwise service it from the side away from the parapet?


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## fatboy (Dec 8, 2010)

I still keep coming back to, if you require them in a commercial (typical flat roof) installation, are you going to require them on a sloped roof (typical residential) installation. A roof, is a roof, if you require guards on PV installations, then shouldn't it apply to all? (I'm still in the no guards camp, BTW)


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## Dr. J (Dec 8, 2010)

If an item that requires occasional clearing of leaves triggers a guardrail, how about a gutter?


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## earshavewalls (Dec 8, 2010)

The way the section I am quoting reads is, "Guards shall be provided where.............components that require servicing are located within 10 feet of a roof edge or open side of a WALKING SURFACE and such edge or open side is located more than 30 inches above the floor, roof, or grade below."

So, this would NOT apply to sloped roofs since they are not "walking surfaces". This is a safety issue and we are enforcing this code on all project, including flat roof installations on residential. It is a design consideration that the PV designer needs to take into consideration when sizing and designing such a system. It is not a problem until someone designs a system without taking this issue into mind. As long as you know the rules, you can play the game....and win. If you DON'T know the rules, you will lose a lot of the time, especially once someon who does know the rules comes your way.


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