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PV array mounting hardware choices 12-12 asphalt shingle roof

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  • PV array mounting hardware choices 12-12 asphalt shingle roof

    The house I'm buying is new to me but was built in 2004-5. I'm going to try to make it "net zero" by putting as much PV on the best oriented roof face as can fit. Then doing enough other retrofits such as air sealing and additional insulation to reach net zero. The house just got re roofed with conventional shingles and has 12/12 pitched roofs with 16" OC rafters. Questions: Has anyone used the "PV Stealth" racking system? Has anyone used the "standoff" rack mounting system from esolarwharehouse.com? Key feature of the "standoffs" is elimination of traditional flashing by using a rubber gasket and sealant on the hanger bolt that penetrates the rafter (the hanger bolt is a 3 1/2" x5/16" lag screw on one end and a 5/16-18 bolt on the end where the stand off is attached between the lag end and the machine thread is a 1/2" hex used to drive the lag into the rafter). One thing that might need improvement is that these standoffs use a 1.5" dia sealing washer, I could instead use the 3" dia sealing washers that Quickbolts use but those cost $2.44 each. Is a 1 1/2" dia EDPM sealing gasket good enough? Key feature of the "Stealth" rail system is NO CLAMPS, the panels slip into the racks and thereafter gravity holds them. Comments Please!
    Note I'm using the standoffs to "raise" the array above the roof to "cool" the panels and position them over the roof vents.
    Other details of my "plan" are 52 ea. Silfab 320 W 60 cell panels, 52 ea. Solar Edge 320W optimisers, 2ea. SE 7600HD invertrers.

  • #2
    using hanger bolts and sealant is REALLY old stuff and surprised that people want to move back to that. The flashing systems do NOT leak when installed correctly and it is pretty easy to install them correctly. They will not leak for the life of your system,

    As for "NO CLAMPS" what is wrong with clamps? they work and are highly reliable and almost invisible.
    I would recommend the ironridge solution and you can get it in all black if you like.

    The solutions you are talking about are really to make life easy for lazy installers, not to be more reliable for homeowners.
    a 16.6kW system is pretty large
    OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

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    • #3
      I know that the idea of not having to mess with flashing is attractive but all sealants at some point will degrade from UV. When they degrade and you have a leak you'll have to move your modules then fix the leak.

      Take the upfront work and skip the headache later.

      Comment


      • #4
        Proper installation of ANY lag bolt to a rafter below will use sealant weather a conventional flashing is or isn't used! The sealant will have NO UV exposure ( flashing or washers or gaskets block the UV). Water proofing with the "micro-flashing" is done by a "rubber washer" compressed by a stainless washer which does NOT depend on sealant.
        Newer is not necessarily better! Installers using these products/techniques will be more productive & efficient (install more watts per hour)! Making smart choices is far from being LAZY!
        " What's wrong with clamps? 1; They cause locally high stress on the module frame, 2; They contain additional costs for material and labor. 3; They REDUCE reliability!


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        • #5
          Originally posted by Jerry Liebler View Post
          Proper installation of ANY lag bolt to a rafter below will use sealant weather a conventional flashing is or isn't used! The sealant will have NO UV exposure ( flashing or washers or gaskets block the UV). Water proofing with the "micro-flashing" is done by a "rubber washer" compressed by a stainless washer which does NOT depend on sealant.
          I've seen the rubber washers on TEK screws rot away and vanish in 5 years. Then panels come loose and leak.

          A rubber washer is NOT the same as flashing

          Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
          || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
          || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

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          • #6
            Originally posted by Mike90250 View Post

            I've seen the rubber washers on TEK screws rot away and vanish in 5 years. Then panels come loose and leak.

            A rubber washer is NOT the same as flashing
            There are certainly some types of " rubber' that will "rot" HOWEVER EDPM, a type of synthetic rubber. will significantly "outlive" the asphalt shingles ALWAYS!

            Comment


            • #7
              Originally posted by Jerry Liebler View Post

              There are certainly some types of " rubber' that will "rot" HOWEVER EDPM, a type of synthetic rubber. will significantly "outlive" the asphalt shingles ALWAYS!
              Dude, you came to a forum asking for opinions on a product from owners/pros who have experience in the field and then argue every single point you're given? You're either really set on the product, at which case just buy what you want and install it or you work for the company and are trying to promote/defend their products.

              Either way, why even ask for advice if you're just going to argue and ignore it?

              Comment


              • #8
                Originally posted by Jerry Liebler View Post

                There are certainly some types of " rubber' that will "rot" HOWEVER EDPM, a type of synthetic rubber. will significantly "outlive" the asphalt shingles ALWAYS!
                pretty sure it will not outlive aluminum flashing
                OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

                Comment


                • #9
                  Originally posted by Jerry Liebler View Post
                  Installers using these products/techniques will be more productive & efficient (install more watts per hour)! Making smart choices is far from being LAZY!
                  " What's wrong with clamps? 1; They cause locally high stress on the module frame, 2; They contain additional costs for material and labor. 3; They REDUCE reliability!
                  So you are a peddler with no real experience trying to sell to people with experience.
                  OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

                  Comment


                  • #10
                    I had an engineer friend give me some advice about water proofing buildings. Essentially he said long term that you can not make a building waterproof but you can design it tho shed water efficiently. Flashing does that, especially with a 12/12 pitch. Gravity is your friend because water naturally wants to run downhill.
                    9 kW solar, 42kWh LFP storage. EV owner since 2012

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                    • #11
                      Originally posted by LPG View Post

                      Dude, you came to a forum asking for opinions on a product from owners/pros who have experience in the field and then argue every single point you're given? You're either really set on the product, at which case just buy what you want and install it or you work for the company and are trying to promote/defend their products.

                      Either way, why even ask for advice if you're just going to argue and ignore it?
                      Oh boy start the rubber wars! Jerry was making some points that probably had more complete answers than "we just always do it this way because it has worked for us"

                      EDPM rubber will outlive everything on the roof short of metal. One of its many attributes is vulcanization and sealing which is ideal for roofing materials. UV resistance is off the scale.

                      This is a forum with various ideas and opinions that's what makes it a wonderful place to exchange knowledge, don't close your mind to different ideas. There are always ways that are easier, faster, and better.

                      The PV racking portion of the system appears to be a black hole it's full of ridiculous pricing that ranges from less than $20 to over $60 per panel mount. personally I like to hear all the different
                      types and uses of the racking that might apply to my application, I have a 3in t&g roofing under where I intend to install my solar field, I find it hard to believe that aluminum racking with 6ft roof attachment points would be a better choice than a direct bracket type attachment.

                      Nobody is hurt keep those ideas coming, I still haven't found racking that I feel is right for my job!
                      Those who do, do it!

                      Comment


                      • #12
                        Originally posted by motorcyclemikie View Post

                        Oh boy start the rubber wars! .......... I have a 3in t&g roofing under where I intend to install my solar field, I find it hard to believe that aluminum racking with 6ft roof attachment points would be a better choice than a direct bracket type attachment.

                        ............!
                        Rubber wars, haha. J.P.M. and I have the thermodynamic wars going on another thread.

                        With 3 inch T&G you have great flexibility about where to put your lag bolts. In that case I can see the value of direct attachment of you can get the engineering.
                        9 kW solar, 42kWh LFP storage. EV owner since 2012

                        Comment


                        • #13
                          Originally posted by motorcyclemikie View Post
                          Oh boy start the rubber wars! Jerry was making some points that probably had more complete answers than "we just always do it this way because it has worked for us"

                          EDPM rubber will outlive everything on the roof short of metal. One of its many attributes is vulcanization and sealing which is ideal for roofing materials. UV resistance is off the scale.
                          You do realize that the comparison was actually EPDM to METAL as in flashing.
                          EPDM is not going to outlive flashing and the flashing does not rely on sealants. The small EPDM washer is actually just there to protect the sealant in the alternative. This sealant will dry and crack or not expand as the lumber shrinks and the EPDM washer will do little to help when that happens.

                          OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

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                          • #14
                            I can safely say "The opinions here STRONGLY favor the inclusion of metal flashing at each roof attachment". OK, esolarwharehouse.com offers a suitable 12"x12" aluminum flashing it adds $4 to the cost of the hangerbolt-standoff kit. In the opinion of the people answering their phone it is "optional"

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                            • #15
                              Originally posted by Jerry Liebler View Post
                              I can safely say "The opinions here STRONGLY favor the inclusion of metal flashing at each roof attachment". OK, esolarwharehouse.com offers a suitable 12"x12" aluminum flashing it adds $4 to the cost of the hangerbolt-standoff kit. In the opinion of the people answering their phone it is "optional"
                              I must say this is pretty old school style hanger bolt, through a standoff tube, with a flashing and boot.

                              compare that to this system : https://www.youtube.com/watch?v=ohCCYqT1vgg
                              OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

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