Designing a Wood Stove Hearth – Thermal Mass and Heat Transfer
I ordered the Morso 7110 and am planning a tile hearth and brick/tile wall to go behind the stove.
I was trying to keep the stove pipe in the first rafter bay. Just typing this I realize I could move it over to the second rafter bay, too, which frees me up to make a thicker wall behind the woodstove and still meet the required clearances.
My goal is to make a pretty hearth, and at the same time to hold some heat. I’ve acquired reclaimed brick and 6×6 terra cotta tile. I like the look of the tile and was thinking of covering the brick with tile.
The r value (per inch) of the materials are in the attachment (according to this site)
I’d planned to keep the hearth below the stove fairly thin, with just my terra cotta tile over thinset on jetboard (a backer board suitable for this purpose).
1) Is there an advantage to making the floor portion of my hearth thicker? I HAVE noticed that the hearth below my boyfriend’s stove does warm up after a while. If the added thermal mass would be advantageous I’d consider it. However a thicker hearth will be more of a tripping hazard (the hearth is in a corner but next to a traffic flow)
2) Based on the R values provided, it appears that the tile and thinset will conduct heat better than brick. Am I reading the information correctly? My friend had expressed concern that the tile+thinset+brick+jetboard assembly might not conduct heat back to the bricks adequately, but I’m inclined to think it would be fine.
3) Would you suggest I consider making the (back wall) hearth super thick? Like maybe laying the bricks end-out, and making the hearth wall 8+ inches thick? If I let the chimney go through the second rafter bay then I have plenty of space. Or should I stick with the original plan of using the bricks stacked (mortared) flat or on edge and covering the face with tile.
4) are there any concerns for the integrity of the assembly with a sandwich of jetboard (with a 1 inch min air space created by screw+washer+1″ metal pipe spacer), mortar, brick, thinset, tile, grout. This would be about 5 feet wide and 4 feet tall.
I appreciate any opinions or experience!
Thank you all again,
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