Fisher install rear vent stove pipe guidance

[TomColeman]

Brand new to this forum, I can tell from what I've read this is a good place to learn something.

I'm installing my wife's family Fisher stove (mama bear? (25 x 21 x 24')) into my stand alone single story workshop. The stove has an 8 inch back vent venting. My thoughts were to run stove pipe in the space and chimney pipe through the ceiling and tin roof. To do this I would have to take a 90 degree turn. Due to space in the shop I would like to take the 90 degree turn immediately so the stove can be closer to the wall.

I know there are many things I don't know about the install, at least not yet. My first question here is if a 90 degree turn immediately out of the stove to go vertical causes any venting problems. Is this back vented stove intended to have a longer horizontal run before it goes vertical?

I know with the stove pipe in my space there are clearance rules as well I have to adhere to. I'm going to either put a brick all or some other heat resistant material so I can have the stove closer to the wall.

I'd appreciate any thoughts on the horizontal/vertical question as well as running a stove pipe near the wall. Thank you.

 

[bholler]

Brand new to this forum, I can tell from what I've read this is a good place to learn something.

I'm installing my wife's family Fisher stove (mama bear? (25 x 21 x 24')) into my stand alone single story workshop. The stove has an 8 inch back vent venting. My thoughts were to run stove pipe in the space and chimney pipe through the ceiling and tin roof. To do this I would have to take a 90 degree turn. Due to space in the shop I would like to take the 90 degree turn immediately so the stove can be closer to the wall.

I know there are many things I don't know about the install, at least not yet. My first question here is if a 90 degree turn immediately out of the stove to go vertical causes any venting problems. Is this back vented stove intended to have a longer horizontal run before it goes vertical?

I know with the stove pipe in my space there are clearance rules as well I have to adhere to. I'm going to either put a brick all or some other heat resistant material so I can have the stove closer to the wall.

I'd appreciate any thoughts on the horizontal/vertical question as well as running a stove pipe near the wall. Thank you.
View attachment 306071View attachment 306072View attachment 306073

Run a tee directly off the back of the stove. The clearance for the stove can be reduced to 12 inches with a ventilated heat shield. That means a non-combustible material spaced off the wall atleast an inch with non combustibles spacers. With an inch open top and bottom to allow air flow. The single wall pipe needs 18 inches unshielded 6 shielded

 

[TomColeman]

Run a tee directly off the back of the stove. The clearance for the stove can be reduced to 12 inches with a ventilated heat shield. That means a non-combustible material spaced off the wall atleast an inch with non combustibles spacers. With an inch open top and bottom to allow air flow. The single wall pipe needs 18 inches unshielded 6 shielded

Ok so the stove itself can be 12 inches with the heat shield as described. The pipes (single wall) can be 6 inches from that same shielding. I read this quickly initially, now I think I get it. I'm looking to eventually put a brick wall (space on top/bottom airflow as you described) but in the short term put a non-flammable cement-board like material 1 inch off my wall and design in the space for the bricks that will be 6 inches from the pipe. Do you have any thoughts/recommendations on a cement board-like material that will eventually be behind my brick?

 

[bholler]

Ok so the stove itself can be 12 inches with the heat shield as described. The pipes (single wall) can be 6 inches from that same shielding. I read this quickly initially, now I think I get it. I'm looking to eventually put a brick wall (space on top/bottom airflow as you described) but in the short term put a non-flammable cement-board like material 1 inch off my wall and design in the space for the bricks that will be 6 inches from the pipe. Do you have any thoughts/recommendations on a cement board-like material that will eventually be behind my brick?

Cement board is fine so is sheet metal

 

[coaly]

Your stove is a Grandma Bear. If you set a couple bricks on the floor to raise the cement board, the wall fasteners don’t need to support the weight. And no fasteners in centerline behind stove.

The size of the shield needs to be large enough when measuring in any direction from stove on angles to unprotected wall, no part of stove is less than 36 inches from unprotected wall.

The 12 inch clearance is measured to the combustible, not the shield.

 

[Charlie250]

Your stove is a Grandma Bear. If you set a couple bricks on the floor to raise the cement board, the wall fasteners don’t need to support the weight. And no fasteners in centerline behind stove.

The size of the shield needs to be large enough when measuring in any direction from stove on angles to unprotected wall, no part of stove is less than 36 inches from unprotected wall.

The 12 inch clearance is measured to the combustible, not the shield.

Hey quick question about your post here. Im doing a heat shield on my corner instal baby bear. Im using 4 sheets of 32” wide 60” high 26ga galvanized roofing. Can there be a seem in the back? I was thinking about bending one a few inches on a 90 degree and have it overlapping in the corner and using sheet metal screws to hold it together. I ordered a kit with 1” spacers to attach to the wall. Also the 12” clearance is to the combustable? Thats some good added security.
I guess not so quick sorry for the long post.

 

[coaly]

Minimum thickness is 24 ga. given in NFPA-211

As long as it is continuous. Overlap normally. It’s not the shield material it is the air space behind it that carries the heat away that allows the reduction.

Yes, the clearance is to the combustible, not the shield.

 

[Charlie250]

Minimum thickness is 24 ga. given in NFPA-211

As long as it is continuous. Overlap normally. It’s not the shield material it is the air space behind it that carries the heat away that allows the reduction.

Yes, the clearance is to the combustible, not the shield.

I see a lot if posts that say 28ga is the min. I messed up hopefully they can change my order. Thanks for the info

 

[bholler]

I see a lot if posts that say 28ga is the min. I messed up hopefully they can change my order. Thanks for the info

26 is thicker than 28 your fine

 

[Charlie250]

26 is thicker than 28 your fine

Yes im aware of that. The guy above is saying 24 is the min. What i ordered is 26.

 

[bholler]

Yes im aware of that. The guy above is saying 24 is the min. What i ordered is 26.

Oops sorry.

 

[coaly]

Yes im aware of that. The guy above is saying 24 is the min. What i ordered is 26.

Here is where to find it for yourself;

https://fcpros.com/wp-content/uploads/2023/04/NFPA-211-2019-FR.280.10.pdf

Chapter 13 is solid fuel burning appliances. 13.6 is Clearances and reducing clearances. Read that section to familiarize yourself with all the details using different reduction methods.

To answer your question of gauge required;
See the table 13.6.2.1

(e) is the ventilated shield you are referring to. That gives the minimum thickness.

Never heard of roofing thick enough, but I’m not a roofer.

 

[Charlie250]

Here is where to find it for yourself;

https://fcpros.com/wp-content/uploads/2023/04/NFPA-211-2019-FR.280.10.pdf

Chapter 13 is solid fuel burning appliances. 13.6 is Clearances and reducing clearances. Read that section to familiarize yourself with all the details using different reduction methods.

To answer your question of gauge required;
See the table 13.6.2.1

(e) is the ventilated shield you are referring to. That gives the minimum thickness.

Never heard of roofing thick enough, but I’m not a roofer.

Thanks. Its special order. He just texted me. Order changed to 24ga it was only an extra $20. 4 sheets. 5ft tall. 32” wide 24ga. Ive seen where people cut 1/2” cement board in strips 3” wide and mount that to the wall doubled up to make it 1”. Then mount the shield to that. Could a metal stud be used like this? 5ft tall 1” off the floor. Mount it to the wall then mount the shield to that?

 

[bholler]

Thanks. Its special order. He just texted me. Order changed to 24ga it was only an extra $20. 4 sheets. 5ft tall. 32” wide 24ga. Ive seen where people cut 1/2” cement board in strips 3” wide and mount that to the wall doubled up to make it 1”. Then mount the shield to that. Could a metal stud be used like this? 5ft tall 1” off the floor. Mount it to the wall then mount the shield to that?

I usually use steel studs