I wavered a bit about to tell the town when I built mine.
In the end I'm glad I did.
The Inspector came out....Collected his $25.00 fee. And we talked about the stove for 1/2 an hour.
I think he wanted to buy one when we were done. Great Guy.
Good news was that my insurance company did a "surprise" walk through about a year later. They asked about the stove.
I showed them the Fire inspection sheet and they were happy with that.
In my case I built a hearth that you could change out an engine on. Way overkill.
Still only cost me about $100.00
If you read your manual it will tell you clearance to combustibles.
On most pellet stoves all it says is " under stove must be a non-combustible material" Basically a sheet of tin would meet that requirement.
You can dress it up however you like. Most pellet stove manuals I have seen don't specify an "R" value.
Good Luck,
---Nailer---
This is my post about it way back in 2007
nailed_nailer said:
I just installed my Enviro EF-2 3 weeks ago on a hearth that we built.
Mine is in a corner location and we wanted a pentagon style hearth.
I cut 3/4" plywood to the size I wanted.
I then put a sheet of 24 gauge sheet metal over that.
Then I put a layer of 1/2" of Dura-Rock over that.
All of this was screwed to the existing floor.
Next we layed out a design in 4"X8" paving stones for a border.
Then we filled the border in with 6"x6" paving stones set in a running bond pattern from the front center.
The pave stones were buttered in with thin set.
For grout I used Polymeric sand
http://www.groundtradesxchange.com/pavers/polymeric_sand.htm.
It hardens with water.
I didn't want to use regular grout due to the pave stones being so rough surfaced that I thought the grout would be hard to wash off the faces.
I then wrapped the hearth face in 3" of red oak trim.
We like it.
So far the sand has not moved. Even when vacuumed.
I built the pad about the same as you are describing.
Depending on your stove....all you may really need is a non-combustible material of sufficient dimensions.
That could be a sheet of tin.
Your stove manual will have what is required under it. Most pellet stove don't need much.
As always follow local codes.
Good Luck,
---Nailer---