Metal roof solutions?

[newman_maple]

I have my new evaporator and need to install the roof vents and run the stack through the roof. I have a couple things I need to figure out before cutting the sheet metal.

I have an enclosed carport and want to run the stovepipe through the peak and place 12” vent bases over the pan near the peak. (I discussed some of this in an earlier thread “turbine vents”) I will place rain caps of some type on the vent bases.

I need to know how to correctly mount a flat vent base to the sheet metal roof? I have tried to locate the right product to seal the vent base to the roof without risk of leaking. I will also need to determine the best solution for running the stack through the roof.

Any and all comments/suggestions will be appreciated.

[MapleME]

well, for metal roofing (in a traditional application) its really the same as on an asphalt roof. You cut your hole for the roof jack in the plywood and mount the roof jack witch supports the base stack. The metal roofing, which attaches to the plywood is just cut around the roof jack. you dont need to seal anything up. Now, if you dont have any under roofing (plywood) and you just have some metal roofing spanning the rafters, Im not qualified to weigh in on that.

[newman_maple]

At this time, I have nothing under the metal roof. I plan to place some support under whatever I use to support the vent bases, and stack base.

I plan to go to my local supply store and ask if they can tell me my best options. I would like to have some knowledge of my options prior to going.

[mountainvan]

I did a stack through a metal roof awhile ago. There was a pliable ring that formed to the shape of the roofing and sealed the stack.

[MapleME]

newman, for vents, are you planning on using those 12"x12" attick type vents for above your evap? I may be trying the same thing. I dont have a peaked roof and dont have a hood etc.
MapleME

[newman_maple]

I bought four of these 12" round vent bases on eBay. I offered $4 each and he accepted that offer.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7559308931

It was my cheapest solution (((IF))) I can get them mounted. I was looking into wind directional caps or vacuum caps for them. Not sure what my best choice will be.

[MapleME]

newman, actually a great idea. Heck, for that price, you could make a cover out of some metal and put it on a hinge.
Im in the same predicament- I was thinking about something like:http://www.airvent.com/homeowner/products/staticVents-roofLouvers.shtml

(the bottom one). I thought If I put 4 in a row it would be enough ventilation.

[danno]

For mounting roof jack to metal roof I just used roofing screws used for metal roofing. They have the rubber grommet that gets squeezed between the surface of the roof jack and the screw head to prevent leaking.

I've reinforced the underside of the roof around the jack with 2x4's and also have done it without reinforcing. If you do use 2x4's, if it's for your smoke stack, I would certainly use fire retardent lumber. Get's hot around that smoke stack. If it's for a steam stack, standard 2x4's are fine.


Do not use roofing cement to bond/seal your roof stack to the metal roof around the steam stack! The roofing cement will soften from the heat of your steam stack and your sugarhouse will always stink like new pavement was layed every time you boil.

My roof jack is on the side of my roof, not on the peak. My metal roof is corrugated? (wavey like) and my roof jacks are flat. I was able to keep the snow/rain from running under the roof jack by placing another piece of roofing over the high side of the roof jack. The top of the roofing slides under the peak cover.

[mikemac0818]

Am I understanding you right, in that you are setting up your sugar rig in an enclosed carport? If so and you have just bare metal roofing on the inside you will not need to worry so much about a leak around your roof jack, it will rain inside when ever you boil. The steam will condensate on the underside of the metal roofing and it will rain in there. Just something to think about.

Mike