Best way to finish exterior trim termination thimble?

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jackiel

New Member
Jan 27, 2022
26
Eubank, Kentucky
Well folks,
I got the holes cut to put in my Selkirk DT wall thimble. The interior went pretty well. Lining up the exterior hole and cutting the corrugated metal siding was another story, way harder than I figured it would be.
Now, how should I trim it out? It needs something in between the exterior wall and thimble plate but what to use because of the wall’s ridges? They make foam like corrugated sealing stuff. I was thinking of 1” boards with that shaped foam underneath?
I still have to put silicone around the edges of the pipe. Then I thought I would put the wood trim up and silicone around that edge with the shaped foam under the 1”boards.
Maybe that exterior wall thimble flange should be underneath the siding and use J-Channel? But that’s not going to happen by my hand anyway. I would have to take gutters and all kinds of trim off to do that. I would have to hire it out if that’s what it needs.

I have not yet put high temp sealant on the edges of the pipe at the connecting points per the Selkirk instructions. Is that absolutely required? The dealer told me if I did the pipe edge sealant, I would have a hard time if I ever needed to take apart the pipe for cleaning.
I was about 1 1/2 hours getting the pipe all connected to see if it all lined up.
Also have not put sealant on the Selkirk 3” to 4” adapter that connects to the stove’s cast iron exhaust outlet.

8645231D-D392-441A-B68F-7F3F6E9134B2.jpeg 476144A7-71AC-4AC3-8F79-7D73A0752ABC.jpeg
 

gfreek

Minister of Fire
Nov 5, 2010
1,583
WNYS
. If you are sealing the pipes where they connect together, you are only sealing the air intake for the stove, not the inner pipe exhaust, which has a seal..I've never sealed mine, just silicone caulk where it comes out of the exterior wall thimble...There are locking tabs on the pipes if you want to lock pipes together .Looking at your picture do you have another piece of pipe to extend that out further, the air intake would be blocked if not..
 

Mt Bob

Minister of Fire
Oct 31, 2013
4,075
park county montana
Well,what some do is cut out a square of the metal, frame a wood box,mount and seal. If you need to use stove immediately, you could make a circle of insulation to go around the round part of the thimble. It's main goal is to prevent cold air into the wall,and keep bugs out. If was mine,I would probably get some 1-by, make a square box,notched for the "bumps, it would be shorter on the left as the metal hits the ridge, install with L brackets, then caulk inside and out of the box, insulate and put together.
But that's just me.
 

jackiel

New Member
Jan 27, 2022
26
Eubank, Kentucky
That sounds like a good plan on the trim.
I didn’t realize I was blocking the cold air intake. I have a 12” adjustable slip joint pipe going through the wall and then connected to the 90° elbow. I can scoot the stove back a couple of inches to not block the cold air intake. Would 2” further out do it?
 

gfreek

Minister of Fire
Nov 5, 2010
1,583
WNYS
Install sheet shows minimum 7 inches , wall to termination cap air intake..
22f6a892-d8a8-4149-b3a8-664ee4860181-jpeg.291074
 
Last edited:

rickwai

Minister of Fire
Nov 1, 2011
1,345
ohio
Well folks,
I got the holes cut to put in my Selkirk DT wall thimble. The interior went pretty well. Lining up the exterior hole and cutting the corrugated metal siding was another story, way harder than I figured it would be.
Now, how should I trim it out? It needs something in between the exterior wall and thimble plate but what to use because of the wall’s ridges? They make foam like corrugated sealing stuff. I was thinking of 1” boards with that shaped foam underneath?
I still have to put silicone around the edges of the pipe. Then I thought I would put the wood trim up and silicone around that edge with the shaped foam under the 1”boards.
Maybe that exterior wall thimble flange should be underneath the siding and use J-Channel? But that’s not going to happen by my hand anyway. I would have to take gutters and all kinds of trim off to do that. I would have to hire it out if that’s what it needs.

I have not yet put high temp sealant on the edges of the pipe at the connecting points per the Selkirk instructions. Is that absolutely required? The dealer told me if I did the pipe edge sealant, I would have a hard time if I ever needed to take apart the pipe for cleaning.
I was about 1 1/2 hours getting the pipe all connected to see if it all lined up.
Also have not put sealant on the Selkirk 3” to 4” adapter that connects to the stove’s cast iron exhaust outlet.

View attachment 291257 View attachment 291258
The last install we did thru metal siding we used Duravent. I cut the correct size hole thru the siding, then slid the outside piece in and marked the ribs where the bent edge of the wall thimble laid. Then used a small Dremel Grinder and cut a slot across the rib on my marks. I laid in pretty nice and sealed up well. The thimble we used has the bent return out on the edge, yours looks like there my not have a bent edge?
 

jackiel

New Member
Jan 27, 2022
26
Eubank, Kentucky
I’m beginning to wonder if I should have gotten Duravent instead but got to make the Selkirk work now. I could get the 45° elbow to make the termination tip bent down. I have been thinking about doing that. Seems like bent down would help about possible rain coming in more than straight.
 

Mt Bob

Minister of Fire
Oct 31, 2013
4,075
park county montana
I'm a fan of being farther away from the house than most peoples installs, less chance of soot on side of house.I also am a fan of a "turndown" 45 degree or less, with a vortex cap.
 

jackiel

New Member
Jan 27, 2022
26
Eubank, Kentucky
Install sheet shows minimum 7 inches , wall to termination cap air intake..
22f6a892-d8a8-4149-b3a8-664ee4860181-jpeg.291074
Ugh, I don’t know how I missed that. Was even proud of myself for getting it so close to the wall!

Will have to order a 24” straight piece to go from the 90° elbow, through the wall and out to the termination tip. Won’t be able to use the 12” adjustable pipe because instructions say not to have a connection joint inside the wall. Sure glad I checked and found this forum.
With a 24” piece through the wall, I will have about 10”-11” from the exterior siding to the termination tip…I think.
 

gfreek

Minister of Fire
Nov 5, 2010
1,583
WNYS
Here

16437260549156147865695536394320.jpg
 
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jackiel

New Member
Jan 27, 2022
26
Eubank, Kentucky
Sold! 45° downturn and clearance from the wall looks good.
Getting ready to place an order for the 24” straight and 45° termination elbow. Then out to frame out and seal around the exterior flange with silicone caulk before the heavy rain starts tomorrow then the ice storm Thursday.
 
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jackiel

New Member
Jan 27, 2022
26
Eubank, Kentucky
I just looked at the Selkirk instructions that came with the Up and Out kit and it does not show the 7” diagram on the termination tip. I think That’s why I missed it. It did show it on the instructions I downloaded but only having the phone to go online with, I missed it on that. I should have looked at the online instructions better instead of the paper version Selkirk sent. I like to see printed out instructions but that’s not always possible.
 

gfreek

Minister of Fire
Nov 5, 2010
1,583
WNYS
I just looked at the Selkirk instructions that came with the Up and Out kit and it does not show the 7” diagram on the termination tip. I think That’s why I missed it. It did show it on the instructions I downloaded but only having the phone to go online with, I missed it on that. I should have looked at the online instructions better instead of the paper version Selkirk sent. I like to see printed out instructions but that’s not always possible.
Agree. I try to download them to my laptop or desk top so I can read or print..
 
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