Triangular alcove clearances?

[koppertop]

Howdy everyone!
I'm in the process of getting a spot prepped for a woodstove in our new(ish) to us home. It previously had a gas fireplace which we have never been a fan of. We have had woodstoves in all our previous homes.

The area will be a triangular shaped alcove. I thought I had found the perfect stove. Now I'm having second thoughts/questions.

We are looking at the Ironstrike Performer S210. Of course all the stoves seem to show a straight in install, corner install, and alcove install. We will have a corner alcove. The install/op manual for the s210 it looks like we will be fine on all clearances. Alcove will be 80ish inches tall (minimum 72). Alcove will be less than 48 inches deep (hearth will extend into open room some). Corners of stove will be approximately 7 inches (6 minimum) from combustibles and worst case I can extend the hearth out a bit more to pull the stove out a few more inches if needed. All looking OK.....then in the "brochure" I see it lists a minimum alcove width, 48 inches. Our alcove will taper back to a point.

Thoughts? Is the brochure correct? Why wouldn't they include this minimum alcove width in the install/op manual? Does anyone see a minimum alcove width in the install/op manual and I missed it!? Seems to me the install/op manual would be the "authority" on all things installation and such?

I'll likely be doing all the area prep and hiring a pro to do most of the chimney install/stove hookup. It is permitted and will be inspected as required. I'm not planning to burn the neighborhood down.

Link to manual

https://ihp.us.com/wp-content/uploads/2021/09/900981-00_NC_IRN_S210AGL_EN_IICO.pdf

Link to brochure

https://ihp.us.com/wp-content/uploads/2021/09/785717M_IronStrike_Wood_Stoves_-03.31.21_WEB.pdf

Thanks for any thoughts. If i can figure out how to attach photos I'll maybe post some photos. Really hopeful we can make it work.
KT

 

[begreen]

It's an untested exception which makes it a grey area not covered in the manual. The manual seems consistent. It says:
Alcove Clearances: In alcove installations, only 6” double wall connector pipe can be used (single wall or single wall pipe with shield is not allowed). Minimum alcove width between combustible materials is 48” (1219 mm). Maximum alcove depth is 48” (1219 mm). Minimum alcove height is 72” (1829 mm).

You may need to contact Ironstrike support for this question. Front and top down view sketches would be helpful. Ask if the corner walls were clad with proper NFPA 211 wall shielding (1" air space, open at top and bottom) would help to qualify.

 

[EbS-P]

Just thinking about this a bit. If you meet the minimum distances to combustibles that you would have for a rectangular alcove (thinking shortest distance from back corner of the stove to the wall) wouldn’t it stand to reason that you could fit the rectangular inside of your triangle footprint? If that’s the case and all other distances are net or exceeded i don’t see the larger alcove posting any increased risk. But I don’t underwrite your insurance nor will I be investing any possible claimed.

This rectangul inside the triangle will take up a lot more space. But how is this different than a corner install with a low height ceiling?

More questions than answers.
Evan

 

[gthomas785]

I would just forget the word alcove and treat it as a corner installation.

 

[koppertop]

It's an untested exception which makes it a grey area not covered in the manual. The manual seems consistent. It says:
Alcove Clearances: In alcove installations, only 6” double wall connector pipe can be used (single wall or single wall pipe with shield is not allowed). Minimum alcove width between combustible materials is 48” (1219 mm). Maximum alcove depth is 48” (1219 mm). Minimum alcove height is 72” (1829 mm).

You may need to contact Ironstrike support for this question. Front and top down view sketches would be helpful. Ask if the corner walls were clad with proper NFPA 211 wall shielding (1" air space, open at top and bottom) would help to qualify.

Thanks, begreen. There it is, I did miss it in the manual. I even searched the document for "minimum alcove width" but pdf didn't find it......when I searched for "minimum alcove" it popped up. I was focusing too much on installation clearances on page 8.

Looking at ironstrike's website I don't see any way to contact them. Guess it'll be test for the dealer to see how good their support is. Haven't ordered anything yet, but do have a big hole in the living room....yikes.

Can anyone recommend a good non-catalytic stove for such an install? I'll try and post a photo and sketch immediately following. And I guess to further clarify, we are considering chopping off the back point of the triangle with a short flat wall if that makes sense....although it wouldn't change dims of the remaining space.
Cheers!
KT

 

[koppertop]

In the photo the cardboard is made to the same dimensions as the S210 and placed as close as I can get without having the actual stove itself.

You can also see a short section of 2x4 laying on the floor behind the cardboard (to the right of the impact driver), this is where we are thinking about making the back a flat wall instead of a point as I mentioned above.

The front edge of the stove would be right at the front edge of the alcove. The hearth extends out into the room 16 inches. I can extend the hearth out into the room more if needed to increase clearances in the back/corners and still get 16 inches in front of the stove....

Thoughts? Stove recommendations that would fit this space?
KT

 

[EbS-P]

An alcove probably need three or more walls?

 

[gthomas785]

The manual doesn't seem to give a definition for an alcove, which is a bit problematic. However, if you meet all the clearances for a corner install including the ceiling height, I don't see how an inspector could argue with that.

 

[bholler]

An alcove probably need three or more walls?

It actually has 4 walls. I have never seen a scenario like this called out in a manual so I think it's going to require contacting the manufacturer. I am pretty sure they will say just honor the regular alcove clearance requirements for the closest walls but I am not sure.

 

[koppertop]

Dealer is in contact with the manufacturer. I'll report back with what I hear.

For those still thinking about this like me....

On page 8 of the manual, it lists dimension G, flue collar to corner wall 15", for a corner install (footnote not for alcove). It also lists dimension M, minimum 72" floor to ceiling for that corner install.

So take this hypothetical corner install, and in your mind move it into the center of the room in an "alcove" with the same dimensions. How could this be any different than over in the corner?

I think this is the same thinking that gthomas785 mentioned above....

Regardless of mental gymnastics, waiting to hear what ironstrike (hate the name) has to say.
Thanks for all your thoughts!
KT

 

[bholler]

Dealer is in contact with the manufacturer. I'll report back with what I hear.

For those still thinking about this like me....

On page 8 of the manual, it lists dimension G, flue collar to corner wall 15", for a corner install (footnote not for alcove). It also lists dimension M, minimum 72" floor to ceiling for that corner install.

So take this hypothetical corner install, and in your mind move it into the center of the room in an "alcove" with the same dimensions. How could this be any different than over in the corner?

I think this is the same thinking that gthomas785 mentioned above....

Regardless of mental gymnastics, waiting to hear what ironstrike (hate the name) has to say.
Thanks for all your thoughts!
KT

It's different because of the side wing walls trapping heat. That makes it an alcove and changes everything

 

[begreen]

One option is to open up that area and install the stove as a freestanding corner install. I have never seen a corner alcove defined for a woodstove. It might be more proper to install a smaller, EPA ZC fireplace in that space. They have tested corner install specs.


PE FP25


Astria Montecito

 

[EbS-P]

Can you or have you considered taking out the header across the front and making it flush with the ceiling?

 

[koppertop]

Sorry for the long delay. Shipping delays really slowed down my project and more than one contractor flaked. I had hoped for a contractor to do the chimney install but ended up doing all the work myself after lots of research and too much discussion with the stove shop. Given the project delays, we aimed for a "temporary" finish line that would allow the stove to be usable and allow finish stonework to be done next spring/summer when running a wet saw outside and mixing mortar won't risk hypothermia and frostbite.

We passed frame, chimney, electrical, and "final" inspections and the stove is up and running. Right now, the area is "finished" in durock but will eventually be finished in slate.

Regarding the "alcove" and clearances. The stove shop spoke with ironstrike and it seems that the consensus was the stove (Performer S210) couldn't extend into the kinda-alcove-ish area beyond where it is 48" wide and needed to meet all the other clearances (corner and back of stove to back wall). Additionally, the front of the stove extends into the "not alcove" area of the room some so more arguing could be done regarding is it an alcove or not. I extended the front of the hearth a few inches to bump the stove out from the back a bit more, so we have the minimum clearances plus extra in every instance.

-KT

 

[begreen]

We passed frame, chimney, electrical, and "final" inspections and the stove is up and running. Right now, the area is "finished" in durock but will eventually be finished in slate.

My main concern is the proximity of combustibles to the stove top. What is the front wall construction? Metal studs and cement board or wood studs and sheetrock? What is the opening height, 72"? What is the ceiling of the alcove height where the chimney support box is?

A secondary concern is that if the opening height is 18"-24" lower than the alcove opening height, a lot of heat will be trapped at the ceiling of the alcove. This would be easy to address by adding a large vent grille on the front or a pair of vent grilles on the side faces.

 

[koppertop]

begreen, excellent questions, I'm not sure I follow them all, but will answer what I can and maybe we can clarify the others.

The height from top of hearth to the ceiling where the support box is mounted is currently 79".

What exactly do you mean by "front wall"? All of our framing in this area is 2x4 wood studs. In the alcove-ish area where the stove sits the small rear wall and angled side walls are covered by 1/2" durock. Outside of the alcove-ish area in the existing room proper is finished with sheetrock.

As measured from the flue collar to the durock, we exceed clearances to the "rear" wall and the side/angled walls. Combustible studs and fiberglass insulation would be even further away.

In the attached photo things look a bit compressed. For reference, there is approximately 12 inches between the rear of the stove and the back wall, approximately 15 inches between the flue collar and the back wall.

The two big chunks of slate are in place to keep the stove feet from denting/damaging the durock. My understanding is the durock itself satisfies the 3/8" thick floor non-combustible floor protection.

Thoughts? Questions?
KT

 

[begreen]

No problem, I was still going by the picture posted back in May. Changing the camera angle gives a new perspective where now I see the ceiling height is the same as the opening height. The project looks like it is shaping up nicely.

 

[koppertop]

The project looks like it is shaping up nicely.

Thanks.

The plan was for everything to be complete by fall but shipping delays and lack of a contractor slowed things down. We are happy to have passed final inspection and have a usable stove even though we will need to pop it out and do stone work and trim/finish work next summer.

Happy to once again have cave man TV.
-KT