PV modules near roof edge (commercial)

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earshavewalls

Senior Member
We are having issue with some code items that, if they must be enforced, may limit the size of PV systems on flat roofs.
The California Building Code, Section 1013.5 states:
"Guards shall be provided where appliances, equipment, fans, roof hatch openings or other components that require service 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."

The section goes on to explain the requirements for guards.

The Residential Code does not contain such language, so we are NOT enforcing this on residential PV systems.

However, on commercial projects, this has come into play on a few occassions. The real question is whether or not PV modules fall under the category of "other components that require service". I get mixed responses, depending on who is asked the question. PV manufacturers, for the most part, state that their modules are designed to last 40+ years, but will not state whether or not they require service. Among installers, I get about 50% saying they 'never' require service, with the other 50% saying they are likely to need some sort of maintenance (service) over their lifetime. (I even emailed John Wiles and got a pretty much neutral response, as this is not part of his expertise).

I think I asked this a couple of years ago, and got the 50/50 response. We have been conservative with this issue all along and have considered PV modules as components that require service and this has resulted in some added expense to some projects and resulted in downsizing of the system in at least one instance.

We are debating this issue and are intending to set a policy on how to deal with this situation so that we may be consistent in the future.

So, should guards or 42" parapets be required whenever PV modules are located within 10 feet of a roof edge, for safety reasons? I am also sending a similar inquiry to OSHA to see if I can get them to voice some sort of opinion (wish me luck there....lol).

Wayne Webb
Assistant Engineer
MEP Plan Check
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
However, on commercial projects, this has come into play on a few occassions. The real question is whether or not PV modules fall under the category of "other components that require service".

It doesn't matter. PV modules are equipment.

Guards shall be provided where appliances, equipment, fans, roof hatch openings or other components that require service

'Appliances, equipment, fans, roof hatch openings' are one group of items, 'other components that require service' is another. The 'requiring service' part does not apply to equipment any more than it does to roof hatch openings.
 

Marvin_Hamon

Member
Location
Alameda, CA
This issue comes and goes as it is an AHJ code interpretation issue. I have not seen any indication that AHJs are in mass deciding that PV modules fall under this provision of the UBC.

But that doesn't help much when you run up against one that says it does. I've had it happen once in 7 years. Much like any other code issue that is being interpreted in a way that is not considered the industry "standard" you just have to talk the AHJ into seeing things the way everyone else does, or you just do what they want.

Here is what I talk about, maybe something will be helpful.

PV modules do not require regular "service" like a mechanical device that has to have parts serviced every 1000 hours. They might require repair or replacement but that is not the same as servicing. In those rare instances where repair or replacement is required fall prevention equipment will be used.

1013.5 is for mechanical equipment not electrical equipment. Things that have moving parts that have to be lubricated, wear out, and require regular service. PV modules are not mechanical equipment and do not require periodic service.

The interpretation of the overwhelming majority of the AHJs is that PV module to not fall under this provision.

If someone brings up cleaning as servicing, then I point out that while cleaning in some circumstances might be helpful it is not a required service that is mandated such as a requirement that a mechanical device be lubricated every 1000 hours. If the PV modules are cleaned then the same fall prevention systems that are used for any work on the roof would be used.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
After looking it up, I completely agree with Marvin. Section 1013.5 refers to Mechanical Equipment. PV panels are electrical equipment, not mechanical equipment. (Now if the PV panels are on a tracker then that changes things.)
 

earshavewalls

Senior Member
So far, this is going as I thought it would........some for, some against. I gather that the responses that tend to think of PV modules as equipment requiring service are from jurisdictional authorities, and obviously, the response that does not look at PV modules as equipment requiring service comes from someone who designs these systems. This is where the line has been drawn. As far as jurisdictions being split on this.......I can see that, too.

I don't feel that it is the responsible thing to do to NOT consider PV modules as equipment requiring service. Another argument I heard compared PV modules to cellular antennae on buildings. I disagree with this comparison, since cellular antennae are also installed on poles, trees, high-tension power structures, etc. These are not generally serviced, but are regularly replaced (about every 3-4 years). Another similar issue is the requirements from Fire Departments for clear pathways and break-through areas. These similarly limit placement of panels, but have been accepted (mostly because you just can't argue with a Fire Marshall).

Keep the opinions coming, please. Pro or Con on this issue, I would like to get as many opinions as possible. This issue isn't going away.

Thanks to all who respond.

WW
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
I disagree with this comparison, since cellular antennae are also installed on poles, trees, high-tension power structures, etc.

Well, PV panels are certainly also frequently placed on poles. I don't understand how it is at all relevant whether a type of equipment is ever placed on something that is not a commercial building. I think the comparison is more apt than not.

These are not generally serviced, but are regularly replaced (about every 3-4 years).

Well PV panels, if they are not cleaned, are unlikely to require replacement that often. They may not need to replaced for decades. And replacement is not service anyway, is it? Nor does this piece of code seem to care what the lifetime of the equipment or the service interval is.

I do not consider panel replacement in case of failure to be 'servicing'. These failures aren't supposed to be expected and are in fact relatively rare.

Another similar issue is the requirements from Fire Departments for clear pathways and break-through areas. These similarly limit placement of panels, but have been accepted (mostly because you just can't argue with a Fire Marshall).

I do not think a 3 foot pathway on two sides of a building limits placement 'similarly' to a 10 foot zone on all sides of a building. The latter is literally a 6 and 2/3 size larger problem. I helped install a PV system on a less than 30' wide commercial building. Thankfully the AHJ did not bring up the concern we are discussing, because if they had, I think that perhaps that system simply would not have been built. A 3' distance from all edges was not a problem for the system size in that case, and was required in some places by the (less than 42" high) parapets.

The issue is that a 42" guard is a shading problem, at least on the southern edge. It's almost funny, because if 42" guards are required, then you just about have to move the panels 10 ft away to avoid shading, and then guards are no longer required. So if this piece of code is applied, at least on the southern edge (and to some extent east and west edges), it really becomes not a 'guards are required' zone but rather a 'PV is absolutely excluded' zone. Which seems a little unfair because other equipment can be there as long as there are guards.

I mean these comments mainly as explanations of why the firefighter pathways would be much more easily accepted. But its also true that if applied they often reduce the potential system size on a building, and it should be considered whether that is warranted for the safety concerns.

Keep the opinions coming, please. Pro or Con on this issue, I would like to get as many opinions as possible.

Well, one opinion I have is that personnel who are qualified to install and service PV modules are also, pretty much by definition, trained to use fall protection and recognize fall hazards as a matter of course. I think that is inherently true of PV workers in a way that isn't necessarily the case for, say, HVAC maintenance personnel. The same is true for people who might clean PV panels. (That's not to knock HVAC guys, it's just that HVAC equipment isn't always installed on roofs, and not typically installed on steeply sloped roofs that require fall protection just to work on.)

Thus I think Marvin's argument that 'fall protection will be used' is a strong one when it comes to PV workers. Requiring permanent anchor points around PV installations on commercial buildings (or above a certain system size, period) strikes me as a way to 'do the responsible thing.' Enforcing a guard requirement that was explicitly intended for other equipment, and clearly not written with PV equipment in mind, does not strike me so much that way.

Overall my opinion is that building codes are catching up to PV, and that this provision is not caught up and was not originally intended to apply to PV, and therefore should be interpreted less than absolutely. PV is simply different from the 'mechanical equipment' that this code provision was written for. For example, PV can be pole-cleaned from a distance using a couple different methods that may not actually require being within 10 ft of the edge of a roof just because the panels are there. Not so mechanical equipment that needs interior lubrication or parts replacement.

I think there are ways that codes could evolve to address fall protection around PV systems, without in effect placing onerous restrictions on where PV can be put on commerical buildings. I'd suggest permanent warning signs, permanent anchor points, and/or collapsible guard systems, as starting points.

Okay, now I've written too much. Thanks for reading. :roll:
 

earshavewalls

Senior Member
I was able to contact three very knowledgeable people and got down to the nitty gritty on this one. I sent off similar explanations of the conditions on the project I am checking to the following experts:
John Wiles, Sandia Labs, New Mexico
Tom Meyers, Building Official for the US Dept. of Energy's Solar Decathalon in Washington, D.C.; consultant for the SEIA (Solar Energy Industries Association)
and
Steve Thomas, President of Colorado Code Consulting, Inc.; Also on the code board for the ICC on Means of Egress and Fire Protective Assemblies

After much conversation among all of us, (Steve Thomas works with the folks who wrote Section 1013.5), it was determined that this is up to a case by case determination by each individual AHJ and jurisdiction. Fire codes are almost as restrictive already, but not all areas are enforcing all requirements of the Fire Code. It requires a minimum 4' clear area at all roof edges. This code has been amended locally in some cases, based on who enforces the Fire Code.

Bottom line is that for the project in question, we will allow the panels to be installed with no consideration as to proximity to the roof edge. These are single-story buildings, built in the 1960s, with no parapets. It is not reasonable to make them build guards, which would shade the panels, or to reduce the size of the system, which is already only 30.5kVA. On larger, higher, newer commercial buildings, parapets themselves will limit how close to the roof edge the panels may be placed, simply because of shading, so we are still going to enforce this code the way we have been, on these types of buildings.

The divisions in opinions were very clearly drawn. Those who are involved with research and manufacturing of PV modules are all against any such guard requirements; Those who are charged with enforcing codes are siding more on the requirement for these guards. What was interesting was that installers of these systems were split, nearly 50/50 on the subject.

There is obviously a need for more clarification on this subject. PV panels are NOT mechanical equipment. They "may" require servicing, but mostly just cleaning (which rainfall can take care of in most cases). There may be times where PV modules are damaged by nature (wind, hail, earthquake, hurricane, etc.), but they definitely do not require the kind of servicing that the codes are really speaking to.

I appreciate ALL of the input on this subject. As usual, the codes cannot cover everything. But, I did discover from Steve Thomas and Tom Meyers that they are both on a committee that is working on a specific PV code through the ICC. Let's hope that it covers more specific aspects of these systems than what we currently have in our codes.

Thanks again to all of you code folks out there. This forum is a great tool to bounce this sort of issue off of.
 

Marvin_Hamon

Member
Location
Alameda, CA
earshavewalls, I don't agree with you that the division of opinion on this issue is clearly drawn with AHJs mostly agreeing that the guard requirement applies to PV modules. Out in the field very few AHJs I have talked to, or those I know have talked to, think this applies to PV. In the last 7 years I have had this only come up once when an AHJ wanted to apply it and after a discussion between the AHJ and those involved in the design of the project the AJH was convinced that it did not apply to PV modules. I think there is a very small number of AHJs out there who think it applies, and the result of this is that almost all PV installations today are not set back 10' or guarded.
 
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