Need advice about the one inch spacer wall for wood stove installation

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Gin

New Member
Feb 28, 2015
52
North Carolina
Hello! Some of you may remember me from several weeks back when I was researching for our plans to install a wood burning stove. We purchased a Woodstock Fireview, had a hearth built and tiled per the instructions from Woodstock and will have the stove delivered this week. We wanted to get the stove as close to the wall as possible and were advised by Woodstock to purchase the rear heat shield and install a one inch spacer wall to allow the heat to flow up and away from the interior wall. We plan to do that and tile it as well, over Durock. An employee at the tile store was concerned the tile will be too heavy for the Durock wall. It will be screwed in to the studs in the interior wall and our chimney guy believes it will be secure. Should I be concerned? Has anyone here done a wall spacer installation with tile? Thanks for your help once again.
 
If you use steel 2x4s as your spacers & screw through the Durarock & the steel stud into the framing members in the wall you should be good to go. You'll have 1-1/2" of air flow...
You can use as many screws as you think you'll need for support. Just make sure you also leave a minimum of 1" air flow space at the bottom, too.
 
Building an fancy air gap wall shield like that only accomplishes anything if the owner's manual specifies a reduction in clearances by doing it. Is this just a "feel good" wall shield or are you trying to build it with this air gap for a real benefit such as a lesser clearance to the wall?
 
There are many NFPA wall shields that are tiled, brick or stone veneered. Properly hung it is not going anywhere. Screw it once every 8" per Durock directions. Another method for creating the 1" gap is to snap off long 3" wide strips of Durock, then double them up and mount them to the wall studs as firring strip spacers for the sheets of Durock.

The Fireview manual acknowledges wall shielding for clearance reduction. A proper NFPA 211 wall shield should allow a clearance reduction front the back of the stove to 12". Note that this clearance is measured to the nearest combustible which in this case is the wall behind the wall shield.
 
If you use steel 2x4s as your spacers & screw through the Durarock & the steel stud into the framing members in the wall you should be good to go. You'll have 1-1/2" of air flow...
You can use as many screws as you think you'll need for support. Just make sure you also leave a minimum of 1" air flow space at the bottom, too.

Thank you for this information. I know the contractor mentioned steel screws, so that's good. Don't know what he plans for spacers but now I know of the steel option.
 
There are many NFPA wall shields that are tiled, brick or stone veneered. Properly hung it is not going anywhere. Screw it once every 8" per Durock directions. Another method for creating the 1" gap is to snap off long 3" wide strips of Durock, then double them up and mount them to the wall studs as firring strip spacers for the sheets of Durock.

The Fireview manual acknowledges wall shielding for clearance reduction. A proper NFPA 211 wall shield should allow a clearance reduction front the back of the stove to 12". Note that this clearance is measured to the nearest combustible which in this case is the wall behind the wall shield.

Thanks for this post. It's good to know we can use Durock strips as the spacers, since I don't know what the contractor has planned. I should probably just trust the contractor, who has a great reputation, but since it's fire and all, I'm being a little compulsive, I guess. I also like the idea of using a lot of screws for extra strength. I couldn't find any pictures at Woodstock that showed what looked like a one inched spaced fire wall so I called them too. They said no problem with the tile, but I have gotten much better, detailed information here and I thank you all for that. I feel very comfortable with the tile now. Funny how one ill-informed person can mess with my head so much. I'll be glad when this project is done!
 
Here is an article on building an NFPA 211 wall shield. Besides the 1" air space behind it be sure the bottom and top are open and clear by an 1" to allow good airflow behind it.
https://www.hearth.com/econtent/index.php/articles/stove_wall_clear
As long as you are building the hearth, consider putting down a double layer of the 1/2" Durrock for a little added protection. It's cheap and good insurance.
 
Here is an article on building an NFPA 211 wall shield. Besides the 1" air space behind it be sure the bottom and top are open and clear by an 1" to allow good airflow behind it.
https://www.hearth.com/econtent/index.php/articles/stove_wall_clear
As long as you are building the hearth, consider putting down a double layer of the 1/2" Durrock for a little added protection. It's cheap and good insurance.


Very good article. Thanks. The diagram is very helpful as well.
 
also remember whatever is used for fasteners must not be used in the area directly behind the appliance or connector

Yes, I I saw that on the page with the diagram. Thank you. I'm assuming the chimney guy knows this, but I'll be watching, just in case. I'm sure he'll love that. ;-)
 
Stove clearance is 12" minimum behind the stove there is no way to reduce that and meet code . This would be for your own peace of mind . I would go with Durock wall w/ tile ,ceramic spacers
 
Stove clearance is 12" minimum behind the stove there is no way to reduce that and meet code . This would be for your own peace of mind . I would go with Durock wall w/ tile ,ceramic spacers
Yes but with out the wall sheild the stove needs to be 18" from the combustible wall if it has a factory heat sheild or 30 with out it. So you would still get at least a 6" reduction
 
If you use steel 2x4s as your spacers & screw through the Durarock & the steel stud into the framing members in the wall you should be good to go. You'll have 1-1/2" of air flow...
You can use as many screws as you think you'll need for support. Just make sure you also leave a minimum of 1" air flow space at the bottom, too.
+1 I used steel studs (cut to length) for the heat shield spacer on my last stove. 1/2" durock on top of that - solid as a rock for years. No tiles though (didn't care about that - just a rough finish weekend cabin). The air gap at the bottom is critical. I had this over cabin grade t&g pine where i needed a few inches clearance reduction and the wall behind the shield barely got warm. Great peace of mind IMHO...
 
Stove clearance is 12" minimum behind the stove there is no way to reduce that and meet code . This would be for your own peace of mind . I would go with Durock wall w/ tile ,ceramic spacers

unless ul listed appliance allows further reduction. nfpa states any ul listed clearance supercedes theirs. but you cant stack them. so if your appliance says say 10 inches for example, you can use the listings 10 inches although its under the 12 inch min nfpa 66% reduction. but cannot reduce the 10 inches by 66% or 50%.

example my Englander says with side and rear heat shields and double wall stove pipe appliance clearance to combustable back wall is 5 inches. scroll over to the clearance with nfpa 211 protected surface is still 5 inches.
 
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unless ul listed appliance allows further reduction. nfpa states any ul listed clearance supercedes theirs. but you cant stack them. so if your appliance says say 10 inches for example, you can use the listings 10 inches although its under the 12 inch min nfpa 66% reduction. but cannot reduce the 10 inches by 66% or 50%.
example my Englander says with side and rear heat shields and double wall stove pipe appliance clearance to combustable back wall is 5 inches. scroll over to the clearance with nfpa 211 protected surface is still 5 inches.
Yes but i already gave the info per the ul listing for this stove 30" with no shield 12" with one still a large reduction and still well worth doing. if it is a listed stove 211 doesn't mean much just follow the instructions
 
You may get the stove very close to the wall and have it protected properly, but you will still need to have the proper clearances on the chimney pipe exiting the stove. What I'm trying to say is don't forget about your smoke pipe while in the design stage. There is a difference between single wall and double wall pipe. If I remember correctly single wall needs at least 18" clearance's to combustibles, and double is 12" from outside wall to nearest combustible.
 
If I remember correctly single wall needs at least 18" clearance's to combustibles, and double is 12" from outside wall to nearest combustible.
Single wall is 18" but with a wall sheild it goes down to 6" and double wall is 6" but that is all in the instructions for the stove the clearances they set override code so go by what ever the instructions say
 
Something like this.
 

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single wall is 18" and double wall is 9" half of 18 obviously . And yea if your stove manufacturer says you can be closer then it's obviously okay. I was just making sure you weren't trying to put it closer than 12" but I still stand by my recommendation Durock wall with tile ,ceramic spacers that's the best option. Steel studs are okay but why not go ceramic with the resistance to heat and the cheap cost .
 
Steel studs are okay but why not go ceramic with the resistance to heat and the cheap cost .
I'm a scrounger - spare parts in my case - studs left over from sauna project - worked like a charm.
 
single wall is 18" and double wall is 9" half of 18 obviously .
No double every double wall i have ever seen specs on or used is 6" it is just a pipe with a ventilated shield. And a ventilated shield gives you 2/3 reduction not 1/2. We prefer to use steel studs also i think they are easier to work with personally but any noncombustible will work it comes down to preference.
 
What brand has 8" or 9" to ceiling There may be some for sure but the stuff I have used is 6" no matter what. But like i said you need to follow the manufacturers clearance requirements what ever they say goes
 
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