PV array mounting hardware choices 12-12 asphalt shingle roof
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In this case older is inferior. They are relying on the sealant to last the life of the PV with no other physical barrier for the water.
Even the flashing with boot that they offer is not going to last as long.
If you are talking about attic vents then you can cover them and we have with ironridge just put the rails on either side.
4" below the RAILS? or below the PV modules?
The flashfoot 2 is 3.3" tall. Even the smallest rail, XR10 will add another 1" to that as the rail is 1.75" tall.
or you could use the XR100 rail (this was our pick) at 2.44" tall
Last edited by ButchDeal; 04-05-2019, 02:08 PM.OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNHComment
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All that being said, It's a bad idea. I don't know where you are located, but most AHJs will see plumbing vents under a panel and will not pass your inspection, if you don't pass inspection your POCO may not let you interconnect so you'll have to build an off-grid only system. Then if your house burns down your insurance can latch on to the unapproved work as a reason to not pay out.
You're much better off using one of these:
https://solarbuildermag.com/products...ng-vent-pipes/
Hell, even an AAV will be better but some AHJs may complain about those as well and they also require that there be other vents in the home.
With all the code stuff out of the way, lets look at the chemistry side of things. One of the purposes of vents is to allow sewer and waste water gases to escape outside your home, if you put a panel above it all those gases are most likely going to cause issues on that panel, it could cause corrosion or even cause the adhesive to fail.
Lastly, the other type of vent is for exhaust fans, these just move moisture from indoors to outdoors. lets say it cold outside and warm inside, that combination will cause moisture to build up under your panel which could cause its own set of issue along with mold build up.
if you're trying to maximize the roof area just do it the right way and move the pipe or use a roof jack or ask your AHJ about AAVs. Don't cut corners because there's nothing worse than failing an inspection and having to undo your work, make the change then redo your work a second time.Comment
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IPC P3103.1.3 does allow the pipes to be covered but they must be 2" above the roof, it also has rules for protection from wildlife and debris.
All that being said, It's a bad idea. I don't know where you are located, but most AHJs will see plumbing vents under a panel and will not pass your inspection, if you don't pass inspection your POCO may not let you interconnect so you'll have to build an off-grid only system. Then if your house burns down your insurance can latch on to the unapproved work as a reason to not pay out.
You're much better off using one of these:
https://solarbuildermag.com/products...ng-vent-pipes/
Hell, even an AAV will be better but some AHJs may complain about those as well and they also require that there be other vents in the home.
With all the code stuff out of the way, lets look at the chemistry side of things. One of the purposes of vents is to allow sewer and waste water gases to escape outside your home, if you put a panel above it all those gases are most likely going to cause issues on that panel, it could cause corrosion or even cause the adhesive to fail.
Lastly, the other type of vent is for exhaust fans, these just move moisture from indoors to outdoors. lets say it cold outside and warm inside, that combination will cause moisture to build up under your panel which could cause its own set of issue along with mold build up.
if you're trying to maximize the roof area just do it the right way and move the pipe or use a roof jack or ask your AHJ about AAVs. Don't cut corners because there's nothing worse than failing an inspection and having to undo your work, make the change then redo your work a second time.
Putting a panel over a vent is simply a non thinking invitation to trouble. It's simply stupid.Comment
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In this case older is inferior. They are relying on the sealant to last the life of the PV with no other physical barrier for the water.
Even the flashing with boot that they offer is not going to last as long.
putting PV modules over stack pipes is not up to plumbing code either. They should be relocated or left exposed.
If you are talking about attic vents then you can cover them and we have with ironridge just put the rails on either side.
4" below the RAILS? or below the PV modules?
The flashfoot 2 is 3.3" tall. Even the smallest rail, XR10 will add another 1" to that as the rail is 1.75" tall.
or you could use the XR100 rail (this was our pick) at 2.44" tall
I'm simply not going to use clamps IMHO they are truly old school and obsolete! That means I will not be using Iron Ridge rails. I am considering using the flashfoot 2 but to get adequate clearance I might have to add a layer of N S rails under the E W rails that hold the PV modules.Comment
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The vents I'm planning to cover are NOT plumbing vents they are attic vents. What I'm looking for is more than 3 5/8" between the back of the PV module and the shingles.
I'm simply not going to use clamps IMHO they are truly old school and obsolete! That means I will not be using Iron Ridge rails. I am considering using the flashfoot 2 but to get adequate clearance I might have to add a layer of N S rails under the E W rails that hold the PV modules.Comment
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The vents I'm planning to cover are NOT plumbing vents they are attic vents. What I'm looking for is more than 3 5/8" between the back of the PV module and the shingles.
I'm simply not going to use clamps IMHO they are truly old school and obsolete! That means I will not be using Iron Ridge rails. I am considering using the flashfoot 2 but to get adequate clearance I might have to add a layer of N S rails under the E W rails that hold the PV modules.
not sure why You are against the clamps they are very new design for irinridge
OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNHComment
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The 3 1/2" standoff kit ($3.81 in black) from esolarwharehouse.com comes with a 1 1/2" dia sealing washer, possibly not an adequate flashing-waterproofing method. The same company offers a compatible "conventional" flashing for about $4, however one can buy just the 3" " microflashing" from Quickbolt for $2.44. The Quickbolt "pitch" about their waterproofing prowess seen here: https://www.youtube.com/watch?v=4NATgav4ZTE I find convincing. Replacing the 1 1/2" seal & washer of the SWH standoff with the 3" Quickbolt "microflashing" seems like the best alternative & should be as good or better than the all Quickbolt choice that doesn't elevate the rails enough for me. BOM cost $3,81+$2,44+$1.33 ( "L" foot & T bolt)=$7.58/ attachment is well under the Flashfoot2 solution which also isn't high enough.Comment
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The vents I'm planning to cover are NOT plumbing vents they are attic vents. What I'm looking for is more than 3 5/8" between the back of the PV module and the shingles.
I'm simply not going to use clamps IMHO they are truly old school and obsolete! That means I will not be using Iron Ridge rails. I am considering using the flashfoot 2 but to get adequate clearance I might have to add a layer of N S rails under the E W rails that hold the PV modules.Comment
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I think you are making a lot of assumptions that may prove to be wrong. All the electricity produced by the PV panels would, were they not there, be heat energy into the roof and the attic. Instead of the roof absorbing all of the solar energy, and heating up, most of it will result in electricity production or heating of the PV resulting in convection induced airflow between the panels and the roof. Any "dampness: in winter is a sign of another problem with the building, inadequate air sealing of the heated envelope. Despite a slight reduction of vent effectiveness I'd predict measurably LOWER attic temperatures during daylight throughout the year.Last edited by Jerry Liebler; 04-06-2019, 05:25 PM. Reason: lowered the expected attic temperature changeComment
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....... All the electricity produced by the PV panels would, were they not there, be heat energy into the roof and the attic. Instead of the roof absorbing all of the solar energy, and heating up, most of it will result in electricity production or heating of the PV resulting in convection induced airflow between the panels and the roof. .........
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
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-ListerComment
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Another question for the benefit if the ignorant. Why would the attic become damper in winter? Are you referring to relative or absolute humidity?Last edited by Ampster; 04-07-2019, 04:24 AM.9 kW solar, 42kWh LFP storage. EV owner since 2012Comment
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Did you tell us where you are?
Is this a grid-tied system?
Where I am things get really complicated if you go over 10kW nameplate DC.
If so what does your utility have to say about your system size?
I do not know about your building department but mine starts the permit with a letter authorizing a maximum size.
Do you need an engineer to sign your plans? If so IronRidge is a good friend to have because they will engineer your racking system.
What do you have agents clamps and what are you going to do instead? Is your alternative bless by an engineer or will you have to get one to sign for you?
Quick Mount PV is very tempting but as far as I can tell lacks the engineering required to get a permit.
I came here looking for information on Quick Mount PV. Does anyone have experience with them?
Good luck.Comment
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Something else you may wish to consider, is Ridge-line Venting, where there is a continuous vent along the roof ridge. It's small, but the length can add up. Not sure if it's a recommended idea in your area, but popular in minePowerfab 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
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-ListerComment
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I think you are making a lot of assumptions that may prove to be wrong. All the electricity produced by the PV panels would, were they not there, be heat energy into the roof and the attic. Instead of the roof absorbing all of the solar energy, and heating up, most of it will result in electricity production or heating of the PV resulting in convection induced airflow between the panels and the roof. Any "dampness: in winter is a sign of another problem with the building, inadequate air sealing of the heated envelope. Despite a slight reduction of vent effectiveness I'd predict measurably LOWER attic temperatures during daylight throughout the year.Comment
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