? on chase cap/storm collar install

[PeteD]

I have Class A chimney (Security) with a storm collar and a custom stainless steel chase cap, currently being fabricated.

The installation of the chimney with a chase cap is not covered in the manuals for the fireplace or chimney. The chimney will penetrate the chase cover and have a slight gap - do I caulk this? (I think not)

Do I put the storm collar down on top of the chase cap, or leave an air gap (I think leave a gap).

The chase cap will rise up to the opening and have a 2-inch lip around the opening, so water will not be blown in there.

OLD setup:

TIA,
Pete

 

[DAKSY]

I have Class A chimney (Security) with a storm collar and a custom stainless steel chase cap, currently being fabricated.

The installation of the chimney with a chase cap is not covered in the manuals for the fireplace or chimney. The chimney will penetrate the chase cover and have a slight gap - do I caulk this? (I think not)

Do I put the storm collar down on top of the chase cap, or leave an air gap (I think leave a gap).

The chase cap will rise up to the opening and have a 2-inch lip around the opening, so water will not be blown in there.

OLD setup:

TIA,
Pete

Are you simply replacing the chase top on the existing set-up?
If so, are you gonna use the same square cap?
If you are, that style cap fits over the chase top collar & has a feature that fits down
inside the collar as well, so the storm collar isn't needed...
If you're changing out the cap, & it simply attaches to the top of your
Class A, use the storm collar over the chase top collar & in contact with it...
Silicone the joint where the storm collar meets the Class A....
Make sure your new chase top has a small pitch to divert water AWAY from the chimney...
& make sure the chase top collar is WELL siliconed to the chase top...

 

[PeteD]

This is a new install in the old chase - was air-cooled before. Lennox Brentwood with Class A pipe.

Maybe my lingo is not correct or I worded things in a confusing way. Let me try to rephrase.

By chase cap, I mean one of these (currently being fabricated):
http://haveacoollife.com/db5/00493/haveacoollife.com/_uimages/ChaseCover.jpg

My class A chimney will penetrate and extend above the chase cap by about 16 inches. On top of the chimney will be the manufacturers rain cap with spark arrestor:
Rain Cap (top of photo):
http://www.lindemannchimneysupply.com/1ed32c2c0.jpg

I will use the storm collar to prevent water from getting between the chase cap and the class A chimney. The chase cap will be pitched up to its opening to drain water, plus the lip of 2 inches will keep water from entering around the pipe from blowing wind etc.

The storm collar will of course be siliconed very well to the pipe.

Should the bottom of the storm collar be set right on top of the chase cap? And siliconed?

Should I silicone the gap around the chase cap and class A also?

It seems there are 3 potential joints that could be siliconed...but I wonder if letting the area under the storm collar and around the chase cap should be allowed to breathe? This could be done without allowing water to get in as long as the storm collar bottom is within an inch or so of the chase cap.

Thanks,
Pete

 

[DAKSY]

By chase cap, I mean one of these (currently being fabricated):
http://haveacoollife.com/db5/00493/haveacoollife.com/_uimages/ChaseCover.jpg

Chase cap..chase top...same difference...Looks like a quality product...
We make em outta heavy gage aluminum, in lieu of SS, both to cut
down on the cost & increase the workability......

My class A chimney will penetrate and extend above the chase cap by about 16 inches. On top of the chimney will be the manufacturers rain cap with spark arrestor:Rain Cap...The storm collar will of course be siliconed very well to the pipe.
Should the bottom of the storm collar be set right on top of the chase cap? And siliconed?

First of all I don't think the storm collar (SC) will REACH the chase top (CT), but no, you shouldn't need to silicone that area..
Like I said in the first reply, position the storm collar AS FAR DOWN on the Class A as you can...
The underside of the SC should be in contact with the CT collar...
Water will never get deep enuff to get in there...
Any snow build up will tend to run away from the pipe as it melts...

Should I silicone the gap around the chase cap and class A also?

It's not necessary, but you can if you want...
Not gonna hurt anything...

It seems there are 3 potential joints that could be siliconed...but I wonder if letting the area under the storm collar and around the chase cap should be allowed to breathe? This could be done without allowing water to get in as long as the storm collar bottom is within an inch or so of the chase cap.

Just silicone the SC to the Pipe & forget about it...
The way your chase top is manufactured, it'll have some room for air movement -
Chase tops are made to be as square as possible...
The framing on the other hand, almost ALWAYS isn't square, so there'll be gaps under the returns...

 

[PeteD]

Thanks, that is what I thought you meant. The storm collar is about 6 inches high or so, so it will not hit the collar on the chase top, but the rest of your post confirms what I was thinking.

What do you mean by the returns? My chase top (not made by the people in the photo, but same design) will overhang the chase slightly in spots (1/8" or so) because the chase it not square. I also have a 1/4" flare for a drip edge on mine around the bottom of the apron (I think that is what you mean by returns - so yes, you are correct) after it clears the top framing.

Pete