help/ideas for extending my hearth

[ohiohearthstone]

I'm realizing that I need to add on to my hearth area. I've been reading around the site and feel confident I can do this on my own.
I need to add about 10" to meet the minimum 18". I have been playing with the idea of tile or stone.(and if I went with stone can you get custom things made?) . I have found some kind of new tile @ Menards that says it can be put down over plywood. The area that I want to protect is in front of the stove. There is old vinyl under the carpet. I have read about the durarock but I'm asking if this is really needed or can I just get some stone from the landscaping company..cut the carpet..use liquid nails/thinset and be done? I think I'm going to try to trim/1/4 round around what ever I do ...so I'm just trying to brainstorm right now. Yes, I realize I could build a steel frame/durarock-etc and build higher...just trying to get something down now...Before I run all over creation looking..I thought I'd pick your brains. BTW hearth is ~66 3/4 wide.

Now if you are wondering why my $4000 hearthstone is still covered up? I'm still getting a lot of cold air coming from around the stove. I've had the installers out (they only used insulation-no block off) and they say all this cold air is normal. The room gets in the 50's if it's not covered. I'm having them come back out and install a blanket and a blockoff plate. I tried to keep the business local (because we know them).
However, I was told that they have never used block off plates and nobody else has ever had the cold air issue.
I printed off the templates from here and I'm having them come back out and try to do it right. (although they want to charge more for additional installation work..I just want it done right. They were still perplexed about the the blockoff plate and how to seal it where the liner goes through. Have you ever been treated/looked at like you're crazy lol.... From what I've read here..the blanket liner/block off plate should hopefully stop some of this cold air (definitely moving air -not just cold sink from the brick).

I'll keep you posted on the saga..........I just don't know why anything I do can just never be right the first time like everyone's projects here lol.

 

[Bill 700]

Someone correct me if I'm wrong about this, but you may need a layer or two mineral board installed as a first layer on top of the plywood subfloor.

What does the manufacturer's instructions say about the hearth and min. R value?

The Englander stove that I just installed called for a min. R value of no less than 2. I met this with two 1/2" layers of Micore 300 (R 1.03 per 1/2" layer).

The Durock can then be placed on top of the Micore, and the stone on top of the Durock.

Bill

 

[ohiohearthstone]

yeah, Hearthstone calls for a R1.
After reviewing the manual/schematic I am really confused.. 1 pic makes it look like I only need the 9 or 10" that I already have and the other pic makes it look like I need 18... Any experts out there.....?
That is where my questions start to swirl...do I need to worry about all of the cement board (even though I plan on using it)and stuff if all I am doing is being precautionary..
I've had 1 small ash escape...and I'd like to stop further carpet burns..

 

[Bill 700]

The diagrams show that your hearth must extend 18" to the front measured from the fuel door opening (not the ash lip), and that in width, it needs to be 16" wider than the width of the fuel door opening.

The "non-combustible" and "R 1.1" requirements would not apply to anything that you do in excess of the size above.

Logically, with the height of your hearth, your extension would likely be in the "shadow" of the brick hearth, and the specs might seem like overkill, but, if you do have a fire, you certainly don't want to give an insurance adjuster any excuses to deny your claim.

Half inch Durock has an R value of 0.26. https://www.hearth.com/econtent/index.php/forums/viewthread/22201/#237458

You need about a foot of stone to get R 1.

You could put the mineral board down, then the Durock, then nail carpet strips around the edge to hold the carpet tight, then let your stone hang over the edge of the Durock about 1" or so to conceal the edge of the carpet. This makes for a nice neat transition.

 

[FLINT]

Yeah, you can just build a wooden framework that is just shorter than your existing brickwork and then cover it with a layer of plywood and then a layer of durock and then tile on top of the durock - and plan it so that it works out to be the same height when its all completed.

This is what we did, using the directions in this document from woodstock - its a section at the end called, building a hearth pad.

http://www.woodstove.com/pages/hearthplan.html

it was really easy, we did it all ourselves and wasn't expensive. did it all in one evening

 

[Bill 700]

What about the R 1.1 requirement?

Woodstock is apparently saying that only R 0.26 is needed for their stoves, while Hearthstone calls for R 1.1, and Englander calls for R 2.

Ya gotta go with the instructions for your specific stove.

 

[ohiohearthstone]

I think I am going to go with the Micor ..just need to find it now.....
Under the carpet is old vinyl. Does anyone see an issue with me screwing down 1/2" of the micor followed by the tile?
This would then raise the surface about 3/4" above the carpet...but I dont think this should look so bad....

 

[Bill 700]

I found the Micore in stock at a local lumber yard. Apparently home builders use if when installing gas fireplaces in new homes.

The Micore is a mineral board and is somewhat soft. I think that you would be OK gluing it to the vinyl with a good construction adhesive and a few screws. If you are putting large thick pieces of stone on top, you could probable put that directly over the Micore, but if you want to use ceramic tile you would need at least a layer of Durock over the Micore, and even then the grout might crack.

What about using a row of the 12" x 12" x 1-1/2" concrete pavers sold at the big box stores directly over the Micore? You might not even need to mortar these in place, but just butt them tightly against the brick and each other.

Anyone see any problems with this?