Code department giving me a hard time ... need advice on first grid tie installation

[Paul Land]

To repeat: There is more to it than simple clips. The clip design may be P.E. designed/stamped but that's only one component in the design of a racking system, and says nothing about what the clip is attached to. Adequate clips on an inadequate structure is an inadequate design.

Also, looking at your advertising photo, that clip looks like it's for a standing seam roof. Per the OP's sketch, the application roof is shingled.

O.K.

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[J.P.M.]

O.K.

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Your latest included blurb refers to conformance to UL 2703.

UL 2703 covers bonding requirements.

Per UL 2703 itself, it does not cover "...the mechanical and structural requirements of the international building code".

UL 2703 goes on : "The IBC and other codes may have additional requirements. As an example, compliance with the IBC will require development load combinations dead, snow, wind and seismic forces using ASCE 7. These loads will need to be applied in three orthogonal directions and the load resisting elements will be required to adequately support the applied loads.

What you have included says with respect to the mechanical suitability of the clips to which the array is attached. What you have included says the clips conform to UL 2703.

Every municipal building code I've seen sooner or later references IBC and/or ASCE 7, latest ed. and associated reference standards and documents. I'm pretty sure if the OP's AHJ has standards, those are the one he'll be conforming to.

What you have included so far covers electrical bonding. The conversation for this portion of the thread deals with mechanical design requirements for the array attachments to what's often and/or usually the racking and attachments to the roof, and the structure to which the array, usually through the racking, is attached.

What you have included refers to subjects that are very important for other array design considerations but are not directly germane or pertinent to structural design.

[ButchDeal]

Your latest included blurb refers to conformance to UL 2703.

UL 2703 covers bonding requirements.

Per UL 2703 itself, it does not cover "...the mechanical and structural requirements of the international building code".

UL 2703 goes on : "The IBC and other codes may have additional requirements. As an example, compliance with the IBC will require development load combinations dead, snow, wind and seismic forces using ASCE 7. These loads will need to be applied in three orthogonal directions and the load resisting elements will be required to adequately support the applied loads.

What you have included says with respect to the mechanical suitability of the clips to which the array is attached. What you have included says the clips conform to UL 2703.

Every municipal building code I've seen sooner or later references IBC and/or ASCE 7, latest ed. and associated reference standards and documents. I'm pretty sure if the OP's AHJ has standards, those are the one he'll be conforming to.

What you have included so far covers electrical bonding. The conversation for this portion of the thread deals with mechanical design requirements for the array attachments to what's often and/or usually the racking and attachments to the roof, and the structure to which the array, usually through the racking, is attached.

What you have included refers to subjects that are very important for other array design considerations but are not directly germane or pertinent to structural design.

This makes since that it is talking about bonding since the OP is using a railless mounting system the AHJ is concerned about bonding.
Use a railed system that has that built in, or add some ground wires...

[J.P.M.]

This makes since that it is talking about bonding since the OP is using a railless mounting system the AHJ is concerned about bonding.
Use a railed system that has that built in, or add some ground wires...

I must not have explained my point well: UL 2703 has nothing to do with checking support strength or structural design. It therefore has no bearing on checking or rating a design for wind, seismic or other loading considerations.

To think, or say, or imply by reference that it does, as Paul Land has done, is incorrect. Those clips that Paul Land references may conform to UL 2703, but the that conformance, in itself, says nothing about their suitability in terms of mechanical design.

My point was and remains: Those clips may be fine from a strength and fit for purpose mechanical design standpoint for the OP's application, but what Paul Land has provided does not confirm that. Also, even if the clips are suitable, that says nothing about the suitability of the roof or any of the rest of what the array uses for support.

FWIW, I think those clip[s look rather flimsy, but unless I have specs and calc. them out for this application, I can't render an opinion.

Butch: To your point about the AHJ - that body is indeed concerned about bonding, and that's where UL 2703 comes into consideration. As we all know, there are any number of issues that the AHJ is also concerned with, and all are important, but in the main, unrelated to strength design or checking a design for suitability from a mechanical standpoint whether or not a P.E. is required to be involved.

[Paul Land]

I must not have explained my point well: UL 2703 has nothing to do with checking support strength or structural design. It therefore has no bearing on checking or rating a design for wind, seismic or other loading considerations.

To think, or say, or imply by reference that it does, as Paul Land has done, is incorrect. Those clips that Paul Land references may conform to UL 2703, but the that conformance, in itself, says nothing about their suitability in terms of mechanical design.

My point was and remains: Those clips may be fine from a strength and fit for purpose mechanical design standpoint for the OP's application, but what Paul Land has provided does not confirm that. Also, even if the clips are suitable, that says nothing about the suitability of the roof or any of the rest of what the array uses for support.

FWIW, I think those clip[s look rather flimsy, but unless I have specs and calc. them out for this application, I can't render an opinion.

Butch: To your point about the AHJ - that body is indeed concerned about bonding, and that's where UL 2703 comes into consideration. As we all know, there are any number of issues that the AHJ is also concerned with, and all are important, but in the main, unrelated to strength design or checking a design for suitability from a mechanical standpoint whether or not a P.E. is required to be involved.

Paul Land was just posting that theres more and more use of rail less systems that are similar ie: Kenic's Eco-X mounts. Paul Land did not make any statement about the structural integrity of the building. Rail less systems are a proven bonded system fully capable of supporting a well designed PV System. It's about personal preferences, material and aesthetics. Fl requires 250 mph wind test and these were designed in Florida for Florida's violent weather.

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[J.P.M.]

Paul Land was just posting that theres more and more use of rail less systems that are similar ie: Kenic's Eco-X mounts. Paul Land did not make any statement about the structural integrity of the building. Rail less systems are a proven bonded system fully capable of supporting a well designed PV System. It's about personal preferences, material and aesthetics. Fl requires 250 mph wind test and these were designed in Florida for Florida's violent weather.

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Correct, Paul Land did not make any statements with respect to building or roof suitability. That was part of my point. Stick to the subject and leave irrelevant spec references out of the discussion.

Looks to me like you didn't or don't know UL 2703 has nothing to do with structural design or strength calcs. Makes me wonder why you referenced it.

As for the claims you make above, until you can backup what you write, it's all hearsay. Show me or point to a recognized standard for wind design of structures that requires use of a 250 MPH wind speed for design.

[Paul Land]

Correct, Paul Land did not make any statements with respect to building or roof suitability. That was part of my point. Stick to the subject and leave irrelevant spec references out of the discussion.

Looks to me like you didn't or don't know UL 2703 has nothing to do with structural design or strength calcs. Makes me wonder why you referenced it.

As for the claims you make above, until you can backup what you write, it's all hearsay. Show me or point to a recognized standard for wind design of structures that requires use of a 250 MPH wind speed for design.

When were talking about the PV structure we are talking about Thermal Load, Array Cooling with Direct mount and Stand off or Racking Systems. Again it's about Cost ie: New construction with proper orientation and perfect pitch very expensive or 2X4 Rack with washer locking panels down on the ground very cheap. When talking UL2703 we are talking about standards which Sol Attach Meets. Living in Fl during Andrew Coco Walk was 100% leveled winds topped 250mph.So it's just a Lab # and to be concise the correct lab test is 239mph for SolAttch.

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[J.P.M.]

When were talking about the PV structure we are talking about Thermal Load, Array Cooling with Direct mount and Stand off or Racking Systems. Again it's about Cost ie: New construction with proper orientation and perfect pitch very expensive or 2X4 Rack with washer locking panels down on the ground very cheap. When talking UL2703 we are talking about standards which Sol Attach Meets. Living in Fl during Andrew Coco Walk was 100% leveled winds topped 250mph.So it's just a Lab # and to be concise the correct lab test is 239mph for SolAttch.

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Whatever I write about this topic it seems to me you will come back with stuff that's more irrelevant than your prior fluff. I'm, not wasting any more electrons or my time responding to your sophomoric prattle.

I respectfully suggest other readers take your writings with a good deal of skepticism.

[Paul Land]

Whatever I write about this topic it seems to me you will come back with stuff that's more irrelevant than your prior fluff. I'm, not wasting any more electrons or my time responding to your sophomoric prattle.

I respectfully suggest other readers take your writings with a good deal of skepticism.

O.K. From "The Reluctant Skeptic".
BTW My original post/opinion on building structure was in my first statement in kinics OP, way back the pic of SolAttach was questioned by poster who stated it was for standing seem apps upon updating pics I got trolled . All I was is a lowly PV Installer taking orders from my Foreman . With PV Cert, I can be my own boss

[J.P.M.]

O.K. From "The Reluctant Skeptic".
BTW My original post/opinion on building structure was in my first statement in kinics OP, way back the pic of SolAttach was questioned by poster who stated it was for standing seem apps upon updating pics I got trolled . All I was is a lowly PV Installer taking orders from my Foreman . With PV Cert, I can be my own boss

I rest my case.

Thanx for the Q.E.D.

[KenInNC]

Update: The swell people at ecolibriumsolar.com called my engineering inspector and reported this back :

"Please see the attached updated engineering letter for North Carolina. I received a message from the Plans Reviewer this morning. It sounded like you could pick up your permit, #xxxxxxxx, anytime.

His main concern seems to be with the ability of your existing roof structure to support the additional loads of the solar array. This letter will not satisfy that concern but it has been updated to reference the latest building codes. We are not able to provide a letter addressing your roof

[KenInNC]

Wow the post got cut in half so here is the rest of the story: "

[KenInNC]

apparently not ... the system is not working well for me today. I keep getting cut posts

[KenInNC]

roof

[KenInNC]

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