Single Wall Exterior Chimney

[mcothran]

Hey all, first post here.

I have a woodstove in the house I purchased earlier this year that it attached to black stove pipe, then a through wall kit, then a single wall stainless steel chimney on the exterior. It is all 8" pipe throughout. I didn't realize that the pipe was single wall until after several burns it started dripping creosote along the seams and I took it apart to investigate. I realize the dangers of single wall and not sure how the original builder even got away with installing it as a chimney. That being said I need some option to replace it safely.

I was wondering if I could use a 6" flex liner and pull it all the way through the existing 8" stack? There are two 90º bends, one at the wall leaving the stove, and one on the exterior. I am replacing the existing stove with a new EPA model and want it to be safe and not burn my house down. If I can't line it, what other options are there other than replacing the outside stack?

 

[pen]

Some pics would be great here, it'd help better assess what you are working with and be better able to tell if you have an option such as what you asked about. Pics of the pipe up close, especially where creosote is coming out and also where it makes the penetration through the wall, where it passes by the roofline, etc. As the old saying, one pic is worth 1000 words.

That said, if what you have is what I'm envisioning from how you are describing it, itd sounds like it is time to gut what's there and start new with a class A chimney.

pen

 

[fossil]

Properly installed, the only single-wall piping involved would run from the stove flue collar to the penetration through the structure. That penetration would be made using an approved manufactured adapter. From the point on, everything all the way to daylight is Class A chimney pipe. I'm not really sure, from your description, just what you've got, but I'm pretty sure it's neither safe nor legal. Rick

 

[mcothran]

Properly installed, the only single-wall piping involved would run from the stove flue collar to the penetration through the structure. That penetration would be made using an approved manufactured adapter. From the point on, everything all the way to daylight is Class A chimney pipe. I'm not really sure, from your description, just what you've got, but I'm pretty sure it's neither safe nor legal. Rick

Yes, I know it's neither safe nor legal, thus the reason for either lining it with double wall or replacing it all together as a option if all else fails.

Oddly enough, the wall penetrating part is triple wall.

 

[mcothran]

Some pics would be great here, it'd help better assess what you are working with and be better able to tell if you have an option such as what you asked about. Pics of the pipe up close, especially where creosote is coming out and also where it makes the penetration through the wall, where it passes by the roofline, etc. As the old saying, one pic is worth 1000 words.

That said, if what you have is what I'm envisioning from how you are describing it, itd sounds like it is time to gut what's there and start new with a class A chimney.

pen

Here's exterior and interior pics. The interior pipe is just swiveled up out of the way as the ceiling in my shop is 16ft high. I would love to be able to safely line this versus installing a whOle new stack.

 

[pen]

Is it an actual triple wall thimble going through the block? Or a triple wall "crock" ready to adapt to a real chimney on the other side? Ironically, they put the best piece in the place where it was least likely to need it

Regardless, from what I'm seeing here, I'm going to say that a whole new chimney is in order... I'd hate to see you order chimney parts and not be able to attach it to whatever they are using to go through the block there.

Can you find any tags on triple wall part?

 

[mcothran]

Is it an actual triple wall thimble going through the block? Or a triple wall "crock" ready to adapt to a real chimney on the other side? Ironically, they put the best piece in the place where it was least likely to need it

Regardless, from what I'm seeing here, I'm going to say that a whole new chimney is in order... I'd hate to see you order chimney parts and not be able to attach it to whatever they are using to go through the block there.

Can you find any tags on triple wall part?

Its a full triple wall thimble. No, the only tag that was on it was a barcode and its very worn off. If I have to order a whole chimney will I need to replace the thimble since it is 8" instead of 6" like my new woodstove? or is it ok to use a reducer on the outside and inside?

 

[pen]

If you are doing the whole thing anyway, the parts need to match, so finding a reducer on both ends of that thimble, just to match with that brand for 1 piece, would be ludicrous.

Wish I had better news for you

 

[mcothran]

ughhhhh, well that sucks. I think I will hunt down the builder and break his arms first, then order the parts.

 

[begreen]

I reoriented the pictures and looking at them I agree with Pen. It looks like a bad installation. On the interior the single wall is too close to the ceiling joists. There should be a minimum of 18" clearance. The pipe outside looks like something is amuck. There is all sorts of crud and snot dribbling down the pipe. It does not look like a proper installation from the pipe to the braces. And a 90 deg elbow should not be on exterior pipe. I would replace it all and connect with double wall on the interior.

 

[mcothran]

Well....thanks for your input guys. I kind of figured I was going to have to replace it, but it was worth a shot.

 

[pen]

I reoriented the pictures and looking at them I agree with Pen. It looks like a bad installation. On the interior the single wall is too close to the ceiling joists. There should be a minimum of 18" clearance. The pipe outside looks like something is amuck. There is all sorts of crud and snot dribbling down the pipe. It does not look like a proper installation from the pipe to the braces. I would replace it all and connect with double wall on the interior.

Thanks for flipping things BG! In the other orientation, I didn't notice the clearance issue. Thanks

 

[pen]

Well....thanks for your input guys. I kind of figured I was going to have to replace it, but it was worth a shot.

Fixing it now and sleeping soundly is well worth the investment. Well done for being so cognizant!

 

[begreen]

There is a remote chance that the triple wall is a currently made pipe like DuraPlus. No guarantees but remove the connector and the exterior elbow and post good lit pictures of each end. Perhaps we can identify the pipe. If it is DuraPlus you are in luck. But based on the way this was hacked together I would guess that it is not even class A pipe used for the thimble.

 

[pen]

There is a remote chance that the triple wall is a currently made pipe like DuraPlus. No guarantees but remove the connector and the exterior elbow and post good lit pictures of each end. Perhaps we can identify the pipe. If it is DuraPlus you are in luck. But based on the way this was hacked together I would guess that it is not even class A pipe used for the thimble.

Even so, it sounds like the stove he's running is 6 inch, and the thimble is 8 inch. That being the case, it's time to just junk it. Would seem worthless to stick with 8 inch the whole way, for the added cost when the stove would work best at 6.

 

[begreen]

Good point. I was trying to find some redeeming factor, but it's a stretch.