Hearth Query

[RomanW]

Hey everyone,

So I'm planning on pouring a concrete hearth, and have taped out the approx dimensions of the hearth on my floor. I've gone just a bit bigger on all the clearances except for the sides, which have 7" more added just to line up with the fauxstone wall.

My question is about thickness, or potentially design input as to how the hearth is constructed. Which I know has been discussed on here previously and I have perused. But I feel my situation may be unique in regards to the thickness.

I plan on making the hearth as high or a bit higher than the baseboards (So I can run the trim around the hearth and connect the walls). Now, I'm not sure if I should cut the hardwood and construct the hearth directly on the OSB, or construct it on top of the hardwood. On top seems easier, but on the OSB may provide a more solid base. I'm open to comments on that. Aside from that, I have an Escape 1800, and Drolet claims it doesn't need a hearth with any R value. If this is so, and since I know nothing about concrete aside from how to make and pour it, then what would be a sufficient thickness to hold the 390ish lb stove for years to come? 1"? 2"? I would use a wire mesh regardless to help with it falling apart, and get as much of the bubbles out as I can. Depending on said thickness, my idea was to pour it onto plywood with 1/4" plywood forms, or build a 2x4" frame with a plywood cap and pour the slab on there. The baseboards are 2 1/2" tall, and the hardwood, I believe. is 3/4" thick. It could be 1", I'd have to check again.

Thanks for any input!

 

[EbS-P]

Why do you want to pour concrete? Not being critical just wanting to know your preferences.

 

[begreen]

For ember protection only, a sheet of metal would do. Otherwise, consider tiling on a plywood + cement board sandwich so that it is removable if the house is sold. They make nice stone and even cement looking tiles.

What was there beforehand, a gas or ZC fireplace? Will the hole be getting filled in and a new class A chimney installed?

 

[RomanW]

Why do you want to pour concrete? Not being critical just wanting to know your preferences.

Seemed easier. I've tiled before, and I don't want to have to do grout maintenance LOL

 

[RomanW]

For ember protection only, a sheet of metal would do. Otherwise, consider tiling on a plywood + cement board sandwich so that it is removable if the house is sold. They make nice stone and even cement looking tiles.

Yeah I considered a sheet of metal, but my wife and I decided having a raised hearth is better for the kids. Hopefully it will deter them from going near it lol. I agree about the resale thing, but we wont be moving from this place unless we have to. So it being a bit more permanent is ok. But that being said, I could still do a "floating hearth" and no one would know the difference. The only question is how to protect the hardwood underneath. Felt? A layer of underlay?

What was there beforehand, a gas or ZC fireplace? Will the hole be getting filled in and a new class A chimney installed?

Yup. It was a ZC. https://www.hearth.com/talk/threads/chimney-retrofit.193613/post-2603891

 

[begreen]

I don't think the floor would need additional protection, the hearth pad won't be moving, but a simple barrier like Tyvek would work if desired. It can be built up by using 1 1/8" plywood, then 1/2" cement board, then stone or cement tiles.

 

[RomanW]

I don't think the floor would need additional protection, the hearth pad won't be moving, but a simple barrier like Tyvek would work if desired. It can be built up by using 1 1/8" plywood, then 1/2" cement board, then stone or cement tiles.

Hmm, ok. What's the reason for the cement board? Rigidity?

 

[begreen]

It is to provide a level substrate for the tile/stone/cement topping. The bond will be much stronger for the thinset or mortar bed.

 

[RomanW]

Well 'gents, I've decided to go with tile. Then I can tile up behind the stove and fill in the hole the old stove left behind. Thanks for the tips!