Building a hearth using a thin air space and wire mesh

[Geoff John-West]

Building a hearth using a thin air space and wire mesh.
I am installing a hearth for a Hearthstone Mansfield and would like to get an R1 rating although the manual is nonspecific about this so I got the R value from their other manuals.

Here is my construction:
R.1 1/4" Fiberrock underlay over 3/4" spruce subfloor with 1/4" ventilation holes to an unheated basement
R.9 1/8" tight knit wire mess giving a air space
Sheet Metal
R.2 1/2" Wonderboard thin set and screwed through the metal into the subfloor
R.1 Slate tile 4' x 4' total area

Are the air holes drilled in the subfloor a good idea?
I have read extensively hear and haven't heard of anyone putting wire mess down to give the air space insulation that Hearthstone lists.
The only draw back I see is the floor may have a little too much flex for the tiles to hold but we will have a 500 lbs stove holding things down with little walking on the tiles?

Thanks for any comments
Geoff John-West Edmonton Canada

 

[begreen]

Greetings and welcome Geoff. Can you provide a link to more information about the tightknit wire mesh? I'm not familiar with this material.

As for the ventilation holes, this sounds superfluous. I would avoid swiss-cheesing the subfloor if at all possible.

 

[walmartgreeter]

Hello Geoff.

I think you are a very wise man, i admire you greetly.
I think that the air holes drilled in the subfloor is a wonderful idea.

Thank you and God Bless.

 

[Geoff John-West]

Greetings and welcome Geoff. Can you provide a link to more information about the tightknit wire mesh? I'm not familiar with this material.

As for the ventilation holes, this sounds superfluous. I would avoid swiss-cheesing the subfloor if at all possible.

The wire mess is scrap 80 year old 3' garden fencing that provides at least 1/8" air space when laid down with 4 square inch air pocks between the wires. I have nailed the wire down with galvinized roofing nails.
(The air holes are between the 1 x 8 subfloor boards so the floor is not weakened)

 

[kittykat227]

Oh. Well, I think that if you do that, your house will burn down in a few weeks.

No offense but that was a lame idea.

 

[edthedawg]

How old is this Mansfield? The manual for the most recent model (#8011) is surprisingly unclear on requiring any specific R value. But if you want 1.0 min, and your "open air space" only measures 1/8" vertically, you have nowhere near enough air space to count for much R-value. airspace hearths are usually made from steel studs, hat channel, or masonry blocks. They wind up being about 3 or 4" tall minimum as a result.

If there's any flexure to the floor surface before you tile, you're going to have unsatisfying results.

If you can post pix and/or sketches of what you've done (it sounds like you've already built this?) we can offer better advice probably.

I would never want to drill holes in the floor for purposes of added insulation ability. I do not at all understand what you're attempting to gain by doing this.

Good luck and hope to hear more about your setup.

 

[edthedawg]

and i now officially think this is one of the most bizarre threads i have ever seen here.

 

[gibson]

and i now officially think this is one of the most bizarre threads i have ever seen here.

Either that or the best thread of all time!

 

[begreen]

closing the thread. this is a spoof. all from the same ip address. you win some, and then there are losers out there.The fellow seems to like talking to himself. Maybe he's been out in the wilderness a bit too long.