Solutions for Crock - Terra Cotta

[TerraCotta]

Home is a new build(3 years old). We asked the builder to make it woodstove ready in the basement. So what I have is a crock(6") coming into the room through the Superior Wall from the chimney. A square hole cut into the Superior Wall, crock coming through with gobs of mortar holding it in place. Seems normal.

Unfortunately I have already sheetrocked all the way up to the crock. Was not aware that the crock is not quite as woodstove ready as I thought. Regardless, I know I need to cut some of that sheetrock away and am leaning toward the Insul-Flue Thimble and Assembly.

Here is my question:

Am I going to have to remove that crock? And if so, how?

Is there something that fits around the crock or inside the crock that works similar to the Insul-Flue Thimble?

 

[pen]

Welcome.

What's the inside diameter of that crock?

pen

 

[begreen]

Certainly the drywall should not be close to the crock. If there is framing close to it, that is wrong too. Here's an article on the topic:

https://www.hearth.com/econtent/index.php/articles/passing_a_chimney

 

[TerraCotta]

@ Pen: it's a 6" crock with 8" outside diameter.

@ BeGreen: I installed the drywall. That was ignorance on my part. Have not hooked up woodstove so no fire danger yet.
I read that link earlier. Because it is a Superior Wall, the studs are 24" on center. Because it is somewhat close to one of the Superior Wall metal/foam studs I cannot use either the wall patch or "air pocket" method. It appears, according to the article, my only option is the Insul-Flue Thimble.

 

[pen]

I think it's time to get the air chisel out.

pen

 

[BrotherBart]

And ya gotta find out what that insulation is inside the Superior wall.

 

[pen]

Found this in a pdf on Superior walls

Exterior Holes in Superior Wall Panels – Any exterior holes that may be required for such things as
sanitary soil lines, electrical service entrance cables, or chimney ues, should be made following these simple procedures:
1. Mark-out the location and size of the hole required.
2. Use a masonry hole saw or a hammer drill with a small bit (to drill a series of holes around the perimeter of the
hole). With a hammer and chisel start to work the area inside the small holes until the hole is the required size
and shape.
3. After the pipe is installed, completely seal the entire area around it with a exible sealant to prevent water
penetration. A one part urethane or polyurethane sealant, available from your local hardware store, is recommended.
(Do not use Acytoxy-cure silicones.)

Unfortunately, it really doesn't say poo. Here's the link to where I found that. www.superiorwalls.com/documents/downloader.php?docid=815

The full builder's guide is here, but it only says the same. http://www.superiorwalls.com/tech_archive/?page_id=180

I think I'd be giving them a call.

pen

 

[pen]

How large is the square around that crock? I wonder if they filled in the necessary area around that crock to prevent problems with their insulation.

The only problem now is unless you go w/ a block chimney that 6 in crock is too small to fit a SS thimble through there. What about a block chimney w/ a SS flexible liner?

I wonder if the 8in OD is large enough to fit any insulated thimbles through if you were just to break that crock apart and leave the mortar they put in (assuming it's large enough and protects the insulation)?

pen

 

[TerraCotta]

The insulation is combustable. It's just big slabs of foam glued to the concrete form It's an R11 or 13. Can't remember.
Most of the insulation is cut away from where the crock is currently coming through. Regardless, I plan on cutting even more out.

Barring any other suggestions I'm gonna go ahead and order the Insul-Flue and pick up an air chisel. I'll post a pick later in the week after I've cut out the Insul-Flue template.

Thanks guys.

 

[TerraCotta]

Pen, sorry, you posted a couple more times while I was typing my last post...

If I remember correctly, the square is just big enough for that crock to pass through. Maybe 9 x 9. 10 x 10 at most.

You are losing me on some of your abreviations. I'm a novice at this. What is a block chimney and the SS thimble/flexible liner?

 

[pen]

Sorry!

Block chimney would be a chimney made of concrete blocks. Traditionally, these were lined with terracotta liners. However, there's no reason that you couldn't put a SS (stainless steel) which is insulated inside of one. Depending on how tall your chimney would be, a 5.5 inch liner might work fine and you could then still keep that 6 in crock just as it is.

That is of course, assuming that the installer left the proper clearance to combustibles since an uninsulated piece of pipe would be going through that crock.

What is the clearance to combustibles on the piece you are planning on ordering? Some are only 2 inches. What kind of chimney did you have in mind?

pen

 

[TerraCotta]

Currently I have a block chimney like you are speaking of. I would say that the chimney is about 30 feet tall. Woodstove is in the basement of a 3 story home.

This is the product I was going to order. It would require removal of the crock:

UL Listed Insul-Flue Insulated Thimble(about halfway down the page):
(broken link removed)

You'll see there is a link to the manual there also.

If that 5.5" SS pipe that you were speaking of is uninsulated then I'm still going to have clearance issues.

The Insul-Flue is going to cost me 300-400 bucks so I'm really thinking that I'm gonna have to have a chimney sweep company come out here and look at my situation and offer some advice.