Chimney liner to B-vent connection question

[agrafuese]

Hello all,

We have an old brick chimney that was at one point (before our time) decommissioned and repurposed as a furnace vent using a flexible chimney liner inside. When we bought our home, the chimney was sticking up through the roof, and the chimney liner went up through a metal flat top and ended with a simple rain cap.

However, due to some safety concerns with the external section of the chimney (chimney was leaning above roof line), we have demoed it below the roofline and it now ends inside our attic just below the inside of the roof.

Now, we want to connect the flexible chimney liner to a simple B-vent pipe that will come up through the roof.

Can anyone tell me what kind of connection piece(s) I will need to connect the existing flexible chimney liner to the b-vent that will run above the roof? I know that there needs to be a flashing piece on top of the roof, with the b-vent pipe sticking up through it, terminating with a rain cap. But I'm just not sure how to connect the flexible liner to the b-vent pipe underneath the roof/inside our attic.

If anyone needs help visually understanding what we want to end up with, I found this youtube video that shows what we want, but unfortunately this person's setup is a little different than ours in that he's not using a chimney liner to begin with (his whole setup is rigid b-vent from the start).



Thank you for any help you can provide!

 

[bud16415]

We did something similar when we had a new metal roof put on the house I took the old chimney down to the attic floor. It was at one time used for the gas furnace and also the gas water heater. The new furnace was vented out low on the house with PVC as they do now and I figured out with the new water heater how to do it similarly so I just abandoned the roof exits all together and roofed over where the chimney was.



We likely have someone here that knows what transition piece connects between the single wall liner and the double wall stuff.

Sorry I don’t know that information

 

[agrafuese]

Thanks, Bud. I ended up finding the part by digging around some more. It's simply called a "b-vent connector". The generic name threw me off for a minute when I was researching it before. Here's the item description from Z-Flex, in case anyone else has this question:

https://www.z-flex.com/productcart/pc/B-Vent-Connector-36p389.htm

 

[bud16415]

Thanks, Bud. I ended up finding the part by digging around some more. It's simply called a "b-vent connector". The generic name threw me off for a minute when I was researching it before. Here's the item description from Z-Flex, in case anyone else has this question:

https://www.z-flex.com/productcart/pc/B-Vent-Connector-36p389.htm

That looks like the ticket. Thanks for posting that I'm sure someone will search some day and it will be good information.

How did you go about closing the big hole down to a small one? In my case i converted it to a roof vent and it has worked out well.

 

[agrafuese]

The beauty of our situation is that we're having a new roof put on the house next week (new plywood and everything), so old hole is going away completely and it'll just be the b-vent going through a brand new hole