sealing roof pipes


  #1  
Old 01-04-10, 08:12 PM
3
Member
Thread Starter
Join Date: Jan 2010
Location: USA
Posts: 184
Upvotes: 0
Received 0 Upvotes on 0 Posts
sealing roof pipes

I'm trying to seal a stovepipe on a metal roof. I thought about doing it like this
pic.

Album Photo: ( )

it looks like a slit has been cut across the metal and a half circle is cut out
of the metal on the top edge.The pipe is installed and the collar flat /flash piece is dropped over and slid under the top but over the bottom. The only questionable place is where the ends of the slits are. additional pieces of flashing are slid under the top but over the bottom AND over the sides of the flashing collar. That would leave only the ends of the slits. I guess you paint silicone over it and then tack a square on top and silicone that also.
All parts are tacked with silicone and the top oval is slid over the whole works....now.. does this sound right??? roofing pros..??
 
  #2  
Old 01-04-10, 08:30 PM
M
Member
Join Date: Jan 2010
Location: MA
Posts: 6
Upvotes: 0
Received 0 Upvotes on 0 Posts
Is there any way to install it completely between two ribs (instead of spanning three, as in the photo)? The general idea is correct, similar to a shingle roof, but with the setup in the photo the rib that has been cut looks wide open, or at the most sealed with silicone. That detail will be the first to fail and should be changed.

If you merely used the photo as a visual aid and can install the pipe directly between two ribs (with no need to cut into a middle rib), then as long as the pitch is steep enough to keep water from wicking upwards, its a viable system to lap the metal similar to a shingle roof (as in the photo). Some screws will be necessary to hold the whole thing in place and a sealant should be used around those (under the head of the screw, so that it seals around the screw part itself). I personally hate silicone on a metal roof, I feel it never really adheres well and much prefer to use a urethane based caulking (geocel 3300, sikaflex 1A, or tremco dymonic). I believe you can get at least the sika at HD or the like. Adding a small bit of the caulking under the seams may be overkill but can't hurt.
 
  #3  
Old 01-05-10, 09:32 AM
3
Member
Thread Starter
Join Date: Jan 2010
Location: USA
Posts: 184
Upvotes: 0
Received 0 Upvotes on 0 Posts
the side wing pieces would cover the remaining slit area. And mine would look 5 times better and neater than that pic. Its actually a stovepipe that is going in... I forgot I will have to cut the hole 2 inches oversize for safety
but the rest should work. I also would like to install one of those hinged
pipe holder units that you tighten up when the pipe is level. I guess it could go on top of the flashing piece ...it might make for a slight bulge but the
oval trim should cover that..
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: