Bonding Metal Roofs

[mnash18]

When a Solar Photovoltaic Systems has solar panels mounted on a metal roof, what are the requirements for bonding the metal roof? Should the metal roof be bonding to the main electrical service grounding system?

 

[SeanD]

I have heard some AHJ's asking about this but I have never encountered it myself.

Is this from an inspectors comments? If so ask for a code section. :grin:

 

[TCN]

Many of the attachment designs will have the frame of the array mounted directly, or indirectly through aluminum feet or stainless strut, to the roof. The design of many arrays also will consider the framing under the panels as a bonding means (depends on the manufacturer).
So, if theses are mounted directly to the metal roof, without paint or sealant between the roof and attachment, of course, the metal roof may be considered bonded through the grounding conductor between the array and the disconnect.
I am one that thinks metal siding, gutters, and roofing when near any potential ought to be bonded. That's my thought on it.

 

[wbalsam1]

When a Solar Photovoltaic Systems has solar panels mounted on a metal roof, what are the requirements for bonding the metal roof? Should the metal roof be bonding to the main electrical service grounding system?

In New York state our Residential Code at E3509.1 states in part:..."Where electrical equipment is mounted on conductive roofing or siding, it shall be bonded to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed."

 

[ricaroofers]

There are some installers that might attach it directly to your metal roofing but as the common installation is. There is a frame that should have attached to the roof to hold the solar panels.