Replacing a Vent

[Bob Landry]

Since Keystone couldn't see fit to vent the range hood outside<still steaming about that>, I ordered a Fantastic Vent to replace the one in front of the stove. In the box there is what looks like a foam type sheet of material that looks like it's cut to be a gasket. I'm thinking that on the roof, that assembly should be sealed with Dicor or whatever the current sealant of choice is and not depend on a porous foam gasket to keep water out.

[SteveC7010]

Bob,

From their instructions on their website ( http://www.fantasticvent.com/faq/kno...o_install.html ), they claim it is a closed cell gasket to go between the flange of the housing and the roof material.

But then they also want you to "silicone" the edges after installation which we all know is a no-no on a Dicor roof membrane. Like you, I'm very leery of the foam gasket.

If it was my rig, I'd get a roll of 1" butyl putty tape and place it around the opening instead of the foam gasket. The only issue there is to do it when it's warm enough for the putty tape to squish down properly as you screw in the vent flange.

And when everything is tightened down, I'd use Dicor's self-leveling caulk to cover all the edges and screw heads in the same manner that Keystone originally installs all that stuff up on the roof.

[Jim W]

I installed a Fantastic fan over two years ago on my 5er. I used the close cell foam gasket as a barrier between the flange and rubber roof material as instructed with no leakage or issue with the install. I than sealed the edge of the Fantastic fan edge with Dicor Lap sealant covering all screw heads and extending out at least 2 inches on a side. To me this was the proper way to install and seal the Fantastic fan; the close cell foam piece is nothing more than a gasket under the flange of the Fantastic fan.
Jim W.

[Bob Landry]

Looking at this kit, I don't really see there would be a difference between using the gasket and putty tape. I do think that what is key is the proper application of the Dicor around the base and over the screw heads. That's where you are going to get a good waterproof seal. I have almost a full roll of putty tape in my tool box, so if I have enough to go around, I'll use it. The people at the dealership said one tube of Dicor would go around the vent with a little left over, so I bought two. More is usually better.