another hearth extension question

[atomichawg]

Am planning on extending hearth for oslo using backer board and tile. As there are no r requirements for the oslo, can I just put the backer board down on top of existing hard wood floor and put tile on that, or should I cut out section of floor which would allow for more layers of cement board and thus provide more r value? Does it really matter? Also, I do have an 18 by 48 inch black mat which could sit on top of tile in front of stove to provide a little r value.

 

[firefighterjake]

If you like the look you can go with the first option of going with the non-combustible cement board and tile (I might suggest going with the 1/2 inch Durock (old style, not new) as you would be gaining a bit of R value in the process even if it is not required per the install specs. If you want more R value you can tear out the flooring, but it really isn't necessary unless you want the additional peace of mind . . . me, normally I'm all about extra safety, but I think this would just be more work and isn't really necessary as the hearth will get warm, but it doesn't get really hot. Just going with the Durock is exceeding the manufacturers specs.

 

[szmaine]

Am planning on extending hearth for oslo using backer board and tile. As there are no r requirements for the oslo, can I just put the backer board down on top of existing hard wood floor and put tile on that, or should I cut out section of floor which would allow for more layers of cement board and thus provide more r value? Does it really matter? Also, I do have an 18 by 48 inch black mat which could sit on top of tile in front of stove to provide a little r value.

Not that I'm advocating less when more is better when it comes to safety (or advocating anything all all since I'm no expert).

But if you go they way you are thinking you should be able to sleep at night - so here my experience so far...
Your situation is the same as mine and I made basically a custom stove board that covers and extends the hearth out of cement board and old tin ceiling tiles (really these are steel w/ tin plate).
We have only had our new Oslo up to 450-500 so far but even after hours of burning I can place my hand anywhere on the hearth and keep it there - it just feels toasty.
We used the bottom heat shield and I can put my hand under the stove too -even cooler there than in front of the stove.
I find this amazing that even metal will stay this cool and now understand why Jotul has no recommended R-value - I was very concerned initially.