Picking up a Heritage tomorrow....STOVE QUESTION

[southbalto]

The hearthstone is scheduled to be delivered (to the garage) tomorrow.

The stove will be vented out the back into class a through the wall and up an existing chase.

For the area behind the stove, i plan on tearing out the existing framing (6'/6' area behind the stove). I'll replace the with framing with steel studs covered with durarock then either cultured stone or bluestone.

Question: Should I treat the area behind the stove as a protected surface? Given the materials, is it appropriate to chararactarize the rear wall as non-combustable?

How close can I push the stove back against the wall?

Thanks

 

[begreen]

The wall will not be classified as a protected NFPA surface unless it's vented top and bottom, no insulation in the cavity. That doesn't sound like a good idea for an exterior wall. However, the clearances for the stove are to combustibles. If I understand the plan, the rear clearance would be to the outside sheathing on the house which would be the first combustible behind the stove, if the wall is insulated, with unfaced fiberglass (don't use paper-backed here or that becomes the nearest combustible).

FWIW, it would seem a lot simpler to leave the wall intact and then create an NFPA211 wall shield with pure cement board with the proper air space created by doubling up 3" cement board strips attached vertically to the studs. Because this is a protected surface, the final distance off the finished wall wouldn't be that much different. Just be sure to leave a 1" air gap at the bottom of the wall and top.

If you go with the tearout, it might be a good idea to document the changes thoroughly and get approval from the inspector ahead of time.

 

[southbalto]

The wall will not be classified as a protected NFPA surface unless it's vented top and bottom, no insulation in the cavity. That doesn't sound like a good idea for an exterior wall. However, the clearances for the stove are to combustibles. If I understand the plan, the rear clearance would be to the outside sheathing on the house which would be the first combustible behind the stove, if the wall is insulated, with unfaced fiberglass (don't use paper-backed here or that becomes the nearest combustible).

FWIW, it would seem a lot simpler to leave the wall intact and then create an NFPA211 wall shield with pure cement board with the proper air space created by doubling up 3" cement board strips attached vertically to the studs. Because this is a protected surface, the final distance off the finished wall wouldn't be that much different. Just be sure to leave a 1" air gap at the bottom of the wall and top.

If you go with the tearout, it might be a good idea to document the changes thoroughly and get approval from the inspector ahead of time.

Thanks for the response. You noted above, that the rear cearance would be the outside sheathing. Currently there is a ZC fireplace in the space. I plan to tear out the ZC so the rear clearance would then be to the back of the chase (which is another 18" behind the current fireplace opening).

By tearing out the ZC (and additional sheetrock/wood studs above and to the side) and replacing the with noncombustable materials, I was hoping to have the option to push the stove back within a few inches of the interior rear wall.

I suppose the other option is to remove the ZC and fill the void with 2/4 and sheetrock. Then build a 211 and purchase a rear heat shield.

From the manual:


Using Single Wall or Close Clearance Stove Pipe With Rear Heat Shield AND NFPA 211
PROTECTED SURFACE
# Residential and Mobile Home Installations for USA/Canada
Parallel Installation:
A: Back wall to stove: 4"(10.1 cm)
B: Right sidewall to stove: 6" (25.8 cm)
C: Left sidewall to stove: 6" (25.8 cm)

If I go this route is the rear clearance to the NFPA211? That is do I need to keep the stove 4" off the 211 shield? Or is it still 4" from the protected surface?

Thanks

 

[southbalto]

Here is what I'm working with:

 

[begreen]

That would make this an alcove installation. Read the manual for alcove clearances and construction requirements. There are some very specific constraints for alcoves. For height it will need a minimum of 57" above the stove top unless it's a protected surface.

How wide is the planned space? Also read up on the hearth requirements. This stove needs R 1.2 heat protection on the hearth.

 

[southbalto]

I considered it but I don't want to do an alcove install. The stove will sit entirely inside the room. Imagine the ZC gone and it just drywall striagit to the floor.

I drew the black lines to indicate the area I was considereing replacing with metal studs/durarock/bluestone.

 

[southbalto]

The ZC will be gone but the exterior chase behind and above it will remain. That's where I'll run my new class A.

Question now is
1) whether it's a good idea to repalce the 6'/6' area with metal studs then durarock/bluestone. Will that give me sufficient protection to be able to push the stove back within 3 inches of the interior wall?

2) If I go the heat shield/211 route. What is the 4" min rear clearance to? Would I need to keep the stove 4" off the 211 protection or 4" off the protected combustable (but now protected) wall?

 

[begreen]

Got it, then back to plan A. Looks like they have a newer manual than the one I have. Let me check.

 

[southbalto]

BeGreeen......thanks for the info so far. Really appreicate what you all do here.

Regarding the manual. the one I'm buying is the older model (circa 2001).

The manual is here:

http://www.hearthstonestoves.com/assets/files/document_library/Heritage8020Manual.pdf

 

[begreen]

Ah, that explains it. The clearances are to the combustible wall, not the heat shield. If the stove has a rear heat shield and the wall is a protected surface, then this could be a really snug fit.

 

[southbalto]

Ah, that explains it. The clearances are to the combustible wall, not the heat shield.

Yea, If I can get down to 4" off the interior wall using the 211 and heat shield that might be the better way to go. that way I don't have to tear out all that additional drywall.

thanks again.

I'll up some pictures as I work through the install

 

[Highbeam]

Since the rear clearance with the heat shield is only 7" then I wouldn't bother with the mumbo jumbo of a 211 shield and all that. Just frame in that old fireplace and cover with drywall to match the rest of the wall.

Did you catch the hearth requirement that BG mentioned? It's pretty extreme.

 

[southbalto]

The stove:

I looked at the manual for the older heritage here 8020 http://www.hearthstonestoves.com/assets/files/document_library/Heritage8020Manual.pdf

And the new model on the hearthstone website.


Neither shows the stove having that cast iron back. This is a heritage, correct? Any ideas on where to locate a manual for this stove?

Also, I see from this website( http://good-times.webshots.com/album/560792336AvuGrC?start=24 )
that the 8" by 1" strip of cast iron looks like it belongs on the side of the stove. Any ideas what it's for?