Help with Pad Materials

[jotulburner]

It seems to me Next Gen has no real documentation allowing use as hearth. The old Durock did have supporting documentation.
Wonderboard has no real documentation allowing use as hearth. Hardibacker has no real documentation allowing use as hearth. and none of the other products I see have any documentation allowing use as a hearth. Some mention use as wall heat shield but none specificaly mention Hearth applications. Micore 300 has some tech data that supports use but if I use it I still need some form of cement board to lay tile. This makes it very difficult to construct my own hearth pad.
Are there any products with documentation supporting use as hearth pad ?
Can I pore my own concrete block and lay tile on that. From what I can tell Poor R value 4 inch concrete block = .80 Not what I want to do.
Can I use brick? Also Poor R value. 4 inch brick = .80 Also not what I want.
You would think that a manufacturer would have a product with supporting documentation designed for this application. If none exist what are we to do?

 

[firefighterjake]

I feel your pain . . . it's aggravating for us as well . . . I really, truly wish some of these folks would get their products tested and listed for use as a hearth.

I guess if I were you and building my own hearth right now I would call around and see if any places have the old Durock kicking around . . . that would be my own preferred choice. I would not build my hearth out of concrete block or brick . . . that's just not something I would want to do and I don't know if I would have liked the look. Another possibility is to find some Micore if you need the R value . . . although from what I read this can be quite the challenge.

That said . . . I could not advocate going with an unlisted product, but you obviously have to use some sort of cementious backer board to make the hearth . . . and waiting until (or if) a company gets their product tested and listed is not an option. I know if I were in your shoes I would go with the next, best solution which to me would be to use a cement board of some sort -- I would try to use one of the products that does not contain any filler (cellulose, perlite, styrofoam, etc.) and be sure to place tile or stone over that . . .

Not the best solution . . . but perhaps the solution that utilizes commonsense and best building practices and materials . . . at this time.

 

[jotulburner]

thanks for the info. It is frustrating I like to do all things as carefuly as I can. You would think that there would be a substantial market for an approved product and a company would be doing themselves a favor by getting such a product to the market place.

 

[sksmass]

Call around local lumberyards looking for the "old" Durock. You may be suprised that they still have it and are eager to unload it. Contractors prefer the nextgen because it is lighter. There is no market for the old stuff, EXCEPT for hearths. And only then by people who really know their stuff. So call around.

 

[begreen]

Pure cement board = the original Durock and Wonderboard. Have you checked with local Home Depot and lumber yards to see if they have any of this product left?

 

[AngierNC]

I recently went through the process of re-doing a hearth based on info found on these forums. Calling around to lumber yards and building supply houses was a complete waste of time. I always explained that I was looking for Durock, not the new stuff and 100% of them said they had it in stock. In fact, NONE of them did. In every case, the sales person explained to me (as if it were me who was dense) that "all cement boards are the same". I finally located some Wonderboard at a local Home Depot, in a bin plainly marked "Durock".

The Micore 300 search was just about as much fun. None of the building supply houses in this metro area had ever heard of it. I did locate a source of 4x8 sheets in a city 150 miles away. Finally, the fellow who was selling me the new stove recommended I check with another stove supplier who did a lot of fireplace jobs and built new hearths. Luckily, they stocked 20 x 72" pieces of Micore and were happy to sell me a couple of pieces. They even gave me some tips for installation.