I’m getting ready to start a 8.2KW photovoltaic project on my roof. The panels will mount to the roof on top of aluminum rails that get mounted to brackets that are lagged through the asphalt shingles into the rafters. My question…..what is the best material to weather seal the 5/16″ lag bolts. I’ll be drilling a 3/16″ pilot hole so this material will be squirted into the hole and coated on the threads of the bolts and applied to the bottom of the L-shaped bracket the bolt is holding down.
Thanks in advance for any replies.
Replies
Vulcuum. It will out last the roof.
Who ever invented work didn't know how to fish....
Take a peek upward... thought you might see it quicker with a message directed to you.
LeeLee, Vulcum is a urethane caulk that sticks to just about anything, lasts a long time, and is very waterproof.
When you apply it, don't get it on you or anything you like.Never be afraid to try something new. Remember, amateurs built the ark, Professionals built the Titanic.
Hi IMERC,
I never heard of Vulcuum. I did a Google search and came up with nothing. Can you kindly give me a little info.
Thanks
Sorry about the spelling. It's VULKEM.
Heed CAG's advice
Who ever invented work didn't know how to fish....
Tremco makes it.
Use one part polyurethane. Gun grade. Non-sagging.
It comes in colors to match just about any thing.
I believe that will all you will need. The stuff is unreal. It will gasket anyting you want to.
Lasts longer than permenant. Sticks to anything except water and oil, but it will try to. You get it on you and it will be there for a good while.
Who ever invented work didn't know how to fish....
Thanks to all for the replies. Vulkem it will be. I've used Tremco's rustproofing products before.
And to Eric......That's a good idea using the Weatherwatch under the brackets. Yes,the solar project is a nice size. I'm using 44 Sharp panels at 185 watts each with 4 SunnyBoy 2500 inverters tying into the grid.....no batteries. My local electric company is offering a rebate of $5.00/watt along with New York state tax incentives. Doing the work myself will allow for it to be free so I figured it to be a no brainer. I don't know if the forum wants me to mention companies by name but I'll give it a shot. I got all my equipment from SunWize Technologies in Kingston NY. The panels cost me $3.35/watt and along with all the other stuff like the inverters,disconnect boxes,mounts etc,the bill came to $38,500. The rebate money will come to $40,700 so I still have a couple grand to buy wire,conduit and the like. If you have any more specific questions,feel free to contact me.
Lexel does essentialy the same thing, and will stick even to a wet surface.
A good heart embiggins even the smallest person.
Quittin' Time
Lexel is awesome, but clean it before it sets with lighter fluid or other petroleum solvent.
SamT
I didnt say wet surface. I said water as in lots of it as in lakes, rivers and oceans.
Who ever invented work didn't know how to fish....
ROFLOL
Well, I didn't realize we were talking about caulking up boats and submarines.
I'll bet lexel would work there, though.
; )
A good heart embiggins even the smallest person.
Quittin' Time
I did use it on the my boat and others too.
Who ever invented work didn't know how to fish....
: )
A good heart embiggins even the smallest person.
Quittin' Time
In addition to the sealant, how about a 1" square patch of ice/water shield between the bracket and the shingle for every lag bolt ? Or a high quality O ring ?
Wow, that's a lot of area and power. What is your estimated material cost and supply source for the cells?
Eric S.
Here in rain country, anytime I mount something to a roof, I use a piece of aluminum or galv. steel that can be anchored at one end under the shingles. If you can't find a double offset ( Z shape ) You can fab your own offset with pipe and a piece of metal to set your panels the desired height off the roof.
I have used gallons of vulem and other great products over the years but nothing will last as well as mechanical flashing/attachment. As roofing ages it will shrink and pull away under the caulking. Most caulking isn't supposed to be exposed to the sun and rain without a protective layer of paint anyway. Just like installing a skylight so that the flashing does all the real work. Caulking should only be for air sealing around the top of the curb.
Thanks for all the replies........the Vulkem seems like great stuff and I've used Tremco's rustproofing products before.
Brujenn....I hear what you're saying about mounting under the shingle with an offset,unfortunately I have over 50 penetrations to deal with but maybe I can fabricate something easily....something to think about.