New Stove's Coming! and Spacer Screws

[Vic99]

So I finally ordered a Hearthstone Homestead Soapstone Stove . . . woo-hoo. Should be installed in 2 weeks. Very exciting.

The stove will vent out an existing kitty corner 1920 fireplace in really excellent condition. In order to make side wall clearances, I had to take off some of the trim wood. Underneath I have horsehair plaster and lathe and a bit of fiberglass insulation tucked along the top. We looked at a few options to both be safe and make it look good. We are getting the factory surround that Hearthstone sells to reduce the clearances. This surround will go over the finished brick, but I'll still have about a couple of inches of exposed horsehair plaster. Unfortunately, 1 inch over the lathe is in the noncombustible zone (stove specs say 9 inches from the corner of the stove to the trim).

Plan A)
My original plan was, before the stove is installed . . . . take a flexbond cement adhesive, spread it completely over the brick and lathe/plaster wall and attach either 1/4 inch or 1/2 inch HardiBacker (or durock) to it. Then I'll use more cement to attach 1/4 or 1/2 inch thick slate tile (probably 6 inch square). The area tiled (when the fireplace opening is subtracted) will be 14-15 square feet.

I know that the slate has ~0.1 R value, thus fine for finished look, but not insulation. It also seems that cemented Hardibacker reinforced with screws directly to the studs is bad because both are directly ontop of a combustible. So option A seems out to me, even though they are "noncombustible"


Plan B)
In the research I've done, it seems instead I'll need to use (2"?) screws with 1/2 or 1 inch spacers (ceramic?) to a fix the HardiBacker to the wall studs and then use cement and tiles. About 5-6 inches of this surface will be over lathe/plaster, the other 8 inches over brick. I still wonder about this because even though dead air has a 0.9 R value, isn't the ceramic in the spacer still touching the wood studs?

1) Does Plan B this seem right? Would plan A or a variation of it be safe?

2) Finally, if I need the screw spacers, where can I get them? Are they ceramic or some other material? I live near in Northeastern MA, near Lowell, MA and Nashua, NH.

As always, thanks . . . someday I hope to contribute and help others when they first start out as well.

 

[tutu_sue]

Wow! You're so excited that you made me excited for you, too. I know you're going to love the stove. Please let us know how she burns. I saw the spacer kit at Lowe's last week. They do look to be ceramic. Don't forget to post pics!

 

[Vic99]

Why thank you. I will.

Spacer kit at Lowe's. Thanks.

 

[begreen]

You can also make spacers out of 3-4" wide strips of durock. Use a couple of 1/2" thick strips to create the 1" air gap.

 

[Vic99]

Good idea. Thanks.

 

[Vic99]

Another thought. I have a wooden mantle that will extend about 14 inches above the stove. I realize that will not make clearance.

Is it safe to encase the existing wooden mantle with 1 inch spacers on the bottom and side, then put 1/2 inch durock, then slate? On the top surface, I would just put slate. I figure this would put a non-combustible mantle about 12 inches from this stove, although the core would be 2 inches of wood.

I figure this would give me R = .97 (1 inch air), .26 for 1/2 inch durock for a total R of 1.23.

Safe?

 

[Highbeam]

In all cases when using these spacer setups I was under the impression, actually told, that clearance to combustibles means clearance to combustibles. It doesn't matter if you put space shuttle tiles on that piece of wood or sheetrock, if it is within the stove's specified clearances then you are in violation of the specs.

As such, I never saw the slightest bit of use for the spacer kits except as part of building the R requirements for under the stove. The R-values listed for the hearth pad requirements only apply to the area beneath the stove.

Can't wait to see your Homestead in action.

 

[Vic99]

Highbeam, what you say makes some sense . . . . that said, isn't it fair to say that noncombustible side walls and trim are ultimately anchored to wood studs in most home set ups? Someone may have put tile/durock or a concrete fieldstone behind and to the sides of the stove. These substances are noncombustible but are ultimately attached to be attached to wood in many setups, I would imagine.

Maybe this is easier said: the noncombustible clearance to the stove is 14 inches from the corner of the stove to the wall and from the top of the stove to a noncombustible mantle a 26 inch clearance is required . Which would be safe?

1) WALL: a tile/durock/1 inch space/wooden stud . . . tile face 12 inches from the stove;

2) MANTLE: rock mantle somehow bolted to wood studs . . . rock mantle is 15 inches from the stove;

3) MANTLE: durock/tile mantle only screwed to wood studs . . . mantle is 25 inches from stove

Obviously no wall within 14 inches would work.

Please advise.

 

[begreen]

There can be a metal heat shield made for the mantle in some circumstances. It needs the same 1" stand offs. But before saying this is ok, it would help to see what you are up against. Can you post a picture?

 

[Vic99]

I spent a half a day taking apart things so that ultimately I could see how the mantle is fastened. The mantle is 6 inches into the room and then another 6-8 inches behind the wall.

The mantle is 3 pieces of wood stacked and glued on top of each other. (2 inches thick). I estimate that once the thermashield pad is on the floor (~2 inches high), the top of the stove will be about 13 inches from the bottom of the mantle. The Hearthstone Homestead manual that I got offline said 26 inches to noncombustible mantle.

I'd like to install slate over the brick and below mantle exposed wood. Above the mantle I would like to keep the same.

 

[begreen]

That helps a lot.

You might not like this, but if it were me, I'd remove the mantle completely and be done with it.

As to the gaps on the side, how far in front of the surrounding studs is the brickwork? Assuming that the bricks are an inch proud of the surrounding studs you should have the airgap in the zone required. So tentatively I'd say plan A, but I would use anchors together with the glue to hold up the durock. The outside edges of the durock should be supported firmly.

 

[Highbeam]

Here's the deal, please someone chime in if it has changed, nobody here will ever tell you whether the clearance to combustibles must be an airspace to combustibles or if it can be filled with noncombustible stuff like tile or cultured stone. The example being that if you filled the required clearances with steel plate then that steel would be just as hot as the stove and have zero clearance to the combustible wall.

We can all agree that if you measured your clearances as air space to the face of the wall (regardless of wall material composition) that you would be safe. If you measured this way then you would be 2" short on your side clearances, 12 vs. 14. Can you slide your stove away from the corner to gain clearance?

You've got combustible mantle within the mantle clearances that needs to be removed. 13 vs. 26 is a pretty big violation. Not sure you'd like the looks of a mantle shield. I would also eliminate the mantle and replace it with a new one up higher. Fortunately you don't have an internal stove pipe to worry about with horizontal mantle clearance.

BG: Does an air gap relieve you of manufacturer's required clearances to combustibles? I was under the impression that only the generic 36" clearances could be reduced with an air gap. Manufacturer's specs are solid.

 

[begreen]

Depends on the stove. Some spec out clearances with approved 1" air gap wall shield and others don't. But in this case, the 9" clearance (with surround) is to side *trim*. If the slate tile is carried all the way to the beginning of the corner wall, then it is more than 9" and there is no side trim. This looks ok to me as long as the distance from stove to the side walls is at least 14". But if not, the manual lists clearances to NFPA 211 Protected Surfaces as 12" with single wall and 3" with double wall. Considering this is a corner install and the flue is behind the surround, I think he is being conservative enough. Worse case senario would be to install required side wall shielding.

By manual, it looks to me like the biggest concern is the shielding of the flue at the back of the stove which in this case sits in the surround and backed by the fireplace. So I think plan A (without the mantle) is within the spirit of the manual. What do others think?

 

[elkimmeg]

With all the thought process, why purchase a stove that has so many clearance issues? From you manual 36" is required to the mantel
Even NFPA 211 reduced clearances can only reduce top distances 1/3. Homesaver mantel shield 18"

you may have side wall issues with the notty pine walls, plus hearth pad issues requiring r6.6

spacer can be cut from metal pipe coper pipe as long as the are non combustiable and no screws positions directly behind the stove

One of my suggestions is to loose the wood mantel and install a blue stone one

 

[Vic99]

Boy, this is a longer process than I envisioned . . . even with a pre existing fireplace.

Elk,
I am purchasing the stove because this seems to be one that will heat most/all of my home (1,600 sq. ft.), will fit in the living room, is soapstone (I like the whole idea), and can make use of my exisiting fireplace. I originally wanted to purchase an insert, but couldn't find something that would fit my small fireplace and still heat all/most of the house . . .

I like what I've heard about this stove and want to try to make it work.

Seems that I will have to remove the mantle. I have a non-fireplace contractor friend that will hopefully give me some advice tomorrow on mantle removal without destroying too much.

Also, I am getting a premade Yoder Hearthpad ~2inches tall with a Thermashield (R=3.1). I'm getting the Hearthstone Homestead with 6 inch legs and a bottom heat shield. According to the manual, I need an R = 2.5.


BeGreen said "Assuming that the bricks are an inch proud of the surrounding studs you should have the airgap in the zone required."

When taking things apart, I discoverd what looks like 1/2 inch or an inch fiberglass insulation stuffed between the studs and the brick on the left side as well as along the top of the brick (maybe more up top). Is this ok?

Thanks again,
-Chris

 

[begreen]

The space I was referring to was not the sides of the bricks, but the front face.

This could be a moot point, and is a somewhat grey area. I think you'ill be ok, because the main area that Hearthstone requires shielding to reduce clearances, is the rear flue exit of the stove. This has been taken care of with the back of the stove recessed in the fireplace, behind the surround. But I'm not doing the inspection. I recommend going over your desires with the fellow that will be doing the inspection. If he understands the manual, it seems to me that you stand a good chance he will approve the cautions you are taking. We can speculate this but ultimately it will require the local inspector's approval.

 

[Vic99]

Good idea . . . now if only I could actually talk to the guy pre-appointment . . . the town hall secretary is like his gate guard.

 

[Gooserider]

Good idea . . . now if only I could actually talk to the guy pre-appointment . . . the town hall secretary is like his gate guard.

Lots of building departments have specific hours when they want people to come in and ask questions of this sort - ask if there is such a window. The building inspector SHOULD be willing to talk to you ahead of time if you tell him that you want to be sure what you are doing is acceptable, and the secretary SHOULD be willing to help you find the time to do so... If not, I'd start calling selectmen, the Town Manager, or whoever else is in charge, and making complaints....

Gooserider