Component Assembly Above the Chimney Support Box

Component Assembly Above the Chimney Support Box

With the chimney support box in place, the next step is to assemble the portion of the chimney that extends above the roof.

The vertical double-wall pipes are easy. They fit to each other and the chimney support box with a grooved slot and a quarter turn.

I installed one double-wall pipe, the roof connection components, the second double-wall pipe and then the chimney cap.  All these items are installed while up on the roof.

The first double-wall pipe extends above the roof line by about 18″. The rest of its length extends down to the bottom of the chimney support box.

The reason for only installing one pipe first and then the roof connection components is some items must be slid down

The next item is a rubber boot. It fits around the chimney pipe and is secured to the roof.  This is the primary water prevention element.

This rubber boot was expensive but oh so worth it. It is a universal fit so it fits pipes smaller in diameter than what I have.   At the top are some concentric ‘circle’ patterns molded into the rubber.

These circle markings are labeled with the diameter of various pipe sizes.  The idea it to cut this boot down to the line that matches the pipe you have.

I just used a blade knife.  It was easy to cut and stay on the line.  Just make sure you cut along the correct line.

The bottom of this rubber boot has a 2″ wide pattern of channeled groves. These are designed to channel any water that makes its way under the boot around and down the edges. Very smart design.

In addition, I applied some sealer to the bottom and permiter edges.  After doing this installation I realized putting sealer on the bottom interferes with this channel design. Lesson learned.

On part I just love about this boot is the metal ring that molds to the profile shape of the roof. Not only does it mold to the right shape it accepts screws driven right through it to make a terrific seal.

I first drove a screw through the top of the ridge and made my way to the side edges. This ensured I would not have any excess material clumped up anywhere.

Did I already mention how good of a design this thing is?  Lemme say it again.  So worth the money.

On one part of the installation I had to get a bit creative. I was doing this installation in the winter and it was cold even for South Carolina.

The rubber did not want to stretch around the chimney pipe. I brought out a tub of hot water in a Rubbermaid container. After a ten minute soak it was flexible enough for installation.

I knew it would cool rather quickly in the winter chilly air. I had my wife toss it up to me as I stook on the roof. I carefully made my way over to the chimney pipe.

I expected a bit of a tight fit. Instead it glided right down nice and easy. After it cooled I had to make an adjustment. That was when I found out how tight of a fit it finally settled into.

The next item was a storm collar. This was a simple piece of metal that wraps around the chimney pipe about 2″ above the rubber boot.

This is just an added layer of protection to help deflect rain. This was a rather tight fit but once installed some caulk holds all in place just fine.

After getting all this hardware installed the second chimney pipe connects to the first one with a slot fitting and a quarter turn. The chimney cap connects the same way.

[nggallery id=16]


This is a series of posts that covers stove restoration, fire brick replacement, installing a door seal and a new installation through a metal roof.


Add your voice to this post. I read and respond to every comment.