Stovepipe elbow heat shield

[apersonnameddan]

While switching insurance companies I discovered that my upper elbow going into the thimble is only 17" from the ceiling when it should be "18. I don't really want some big ugly ceiling protection so I'm leaning toward a shield on the pipe. Am I correct in thinking this is an acceptable solution? If so I need to cover the top (horizontal) leg of a 6" elbow and less than 1/2" of the stainless tee snout. The snout is surrounded by a 6" clay thimble liner.
Does anyone have thoughts on how to go about this? Will one of the pre-fab elbow shields cover it or do I need to fabricate something?
I was considering cutting an 8" elbow or piece of pipe to slide around the exposed clay, and adding standoffs to maintain the gap (see sketch below).
Does anyone have other ideas on this? I don't expect this to cause a fire but I am trying to avoid insurance issues etc.

 

[bholler]

That would work. Or you could just switch to double wall pipe. Did they not point out the lack of proper clearances to combustibles going through the wall. Or are there steel studs behind that cement board?

 

[apersonnameddan]

That would work. Or you could just switch to double wall pipe. Did they not point out the lack of proper clearances to combustibles going through the wall. Or are there steel studs behind that cement board?

The cement board has about 1.5" air gap with steel "hat track" run vertically.
I'm actually trying to avoid complaints, not address them. I was drawing up the hearth for initial paperwork with the new insurance company and noticed the 17", I could have drawn it as 18, but I'd rather make it right before they start asking questions.

 

[bholler]

The cement board has about 1.5" air gap with steel "hat track" run vertically.
I'm actually trying to avoid complaints, not address them. I was drawing up the hearth for initial paperwork with the new insurance company and noticed the 17", I could have drawn it as 18, but I'd rather make it right before they start asking questions.

Ok but what is that track mounted to?

 

[apersonnameddan]

The track is on sheetrock. It's my understanding that the air gap with openings at top and bottom should be sufficient. It's pretty similar to the copper pipe, ceramic insulators or other standoffs used for wall protection. Is the sheet metal enough of a conductor or baffle to cause concern?

 

[bholler]

The cement board has about 1.5" air gap with steel "hat track" run vertically.
I'm actually trying to avoid complaints, not address them. I was drawing up the hearth for initial paperwork with the new insurance company and noticed the 17", I could have drawn it as 18, but I'd rather make it right before they start asking questions.

The track is on sheetrock. It's my understanding that the air gap with openings at top and bottom should be sufficient. It's pretty similar to the copper pipe, ceramic insulators or other standoffs used for wall protection. Is the sheet metal enough of a conductor or baffle to cause concern?

Yes that works to reduce clearances for the stove or exposed pipe as long as the stove manufacturer says so. But do you have the required 12" of solid masonry all around that clay crock going through the wall?

 

[bholler]

Going through the wall is where I was referring to clearance problems. And that is the spot where most structure fires related to stoves start. Well that and ash cans are really close

 

[apersonnameddan]

I'm not sure of the dimensions but it's probably not 12" thick. The round part that's visible was cast onto the existing thimble to make it long enough to pass through the wall protection. Inside the wall it is square but probably not much wider or taller than the 18" diameter that's visible. I may have assumed that the existing chimney was sufficient.

 

[bholler]

I'm not sure of the dimensions but it's probably not 12" thick. The round part that's visible was cast onto the existing thimble to make it long enough to pass through the wall protection. Inside the wall it is square but probably not much wider or taller than the 18" diameter that's visible. I may have assumed that the existing chimney was sufficient.

That is commonly what we see and it is not sufficient

 

[begreen]

https://www.hearth.com/talk/threads/chimney-passing-a-chimney-through-the-wall.147754/

 

[apersonnameddan]

Thanks guys,
I guess I may need to pull a sheet of cement board and double check what's in that wall.

 

[apersonnameddan]

I pulled off the top sheet of cement board and poked around. I found that inside the wall the masonry is 12" thick (30" square). That masonry snout was added because the existing thimble was flush with the masonry wall patch. I wanted to extend the thimble through the wall protection. There is also a small air gap (about 1/4") because I slid the 6" clay inside the existing 8" and packed the gap with a ring of gasket rope before installing the stainless liner.