Floor Protection - Hearth Pad

[donnied44]

Hello All,
I know this topic has been discussed but I would like to see if other members here agree. I have a raised fireplace that i will be installing a new hearth stove. The stove will sit on the fireplace hearth which is 12 inches high (from the floor) The owners manuel requires the floor protection to be 1.2 R Value. According to this article:

https://www.hearth.com/econtent/index.php/articles/hearth_design

It lists the R Values for all materials and such including " air space, ventilated " This appears to be the best rated at 1.43 per inch.
Now since there is 12 inches between the front of my stove and where the floor is, can I effectively calculate the R Value to be:

1.43 X 12 = 17.16

Here are two pictures of the install location.
Am I interpreting the R value requirements correctly to believe that I do not need any floor protection since there is 12 inches of air space between the front of the stove and the floor?
Thanks,
D..

 

[Danno77]

I'm not sure if I follow you exactly. the R value is for radiation below the stove, the 16" (I was thinking it was 18") in front is necessary because of ashes and debris that could come out of the stove during reloads. Trust me when I say that you need that at a minimum, but it's much nicer if there is a little more. Man, sometimes the wood will be snapping and popping when it gets that rush of air when you open the door. I've seen sizeable red hot coals launch easily two feet away from the stove.

I hope I understood what you are asking, but it's not the R-value between the front of the stove and the closest piece of floor. sorry if I misunderstood.

 

[donnied44]

I'm not sure if I follow you exactly. the R value is for radiation below the stove, the 16" (I was thinking it was 18") in front is necessary because of ashes and debris that could come out of the stove during reloads. Trust me when I say that you need that at a minimum, but it's much nicer if there is a little more. Man, sometimes the wood will be snapping and popping when it gets that rush of air when you open the door. I've seen sizeable red hot coals launch easily two feet away from the stove.

I hope I understood what you are asking, but it's not the R-value between the front of the stove and the closest piece of floor. sorry if I misunderstood.

Thanks for your answer. I tried rephrasing to make my question more understandable. But the floor protection requirements state 16" to the front, 8" to the sides and rear. It states, "Must have 1.2 R Value" (nothing mentioned about k value)

 

[Danno77]

yep, means exactly what it says. you need a pad that is exactly (stove width+side minimums) x (stove depth +front/back minimums) and then it needs uniform R-Value as given.

If it's going into that opening then just make sure that whatever is under it meets code and that that extends out to the front as far as it should. Looks like One tile+ one brick width, that should be ~16". Does this have to be inspected by insurance or anything?

Cause if they inspect it, then your R value at the frontmost part of your hearth is going to be equal to 8" of brick. does that come to 1.2? edit, just checked. that should be 1.6 at that point. you should be good if I understand what's going on from what you've said and your pics.

 

[donnied44]

Hello All,
I know this topic has been discussed but I would like to see if other members here agree. I have a raised fireplace that i will be installing a new hearth stove. The stove will sit on the fireplace hearth which is 12 inches high (from the floor) The owners manuel requires the floor protection to be 1.2 R Value. According to this article:

https://www.hearth.com/econtent/index.php/articles/hearth_design

It lists the R Values for all materials and such including " air space, ventilated " This appears to be the best rated at 1.43 per inch.
Now since there is 12 inches between the front of my stove and where the floor is, can I effectively calculate the R Value to be:

1.43 X 12 = 17.16

Here are two pictures of the install location.
Am I interpreting the R value requirements correctly to believe that I do not need any floor protection since there is 12 inches of air space between the front of the stove and the floor?
Thanks,
D..

I actually bought a sheet of 1/2" Hardibacker to make a hearth pad, then I read this chart that I posted, and it says Hardibacker only has a 0.26
R value and ceramic tile only has 0.01. I got a long ways to go before I reach 1.2 I need 0.93 more ! I'm not even close. I wonder what materials everybody else has been using to make their hearth pads pass this requirement?

 

[Danno77]

what's under those tiles?

 

[donnied44]

yep, means exactly what it says. you need a pad that is exactly (stove width+side minimums) x (stove depth +front/back minimums) and then it needs uniform R-Value as given.

If it's going into that opening then just make sure that whatever is under it meets code and that that extends out to the front as far as it should. Looks like One tile+ one brick width, that should be ~16". Does this have to be inspected by insurance or anything?

Cause if they inspect it, then your R value at the frontmost part of your hearth is going to be equal to 8" of brick. does that come to 1.2? edit, just checked. that should be 1.6 at that point. you should be good if I understand what's going on from what you've said and your pics.

I just want to make sure it is up to code for my own peace of mind. The stove will extend out of the firebox to about 4" shy of the edge of the existing hearth edge. So it will have 12" of brick under it. So I'm thinking that for the floor protection rule, I might need 12" of floor protection added over that Pergo floor that you see. ( or may not depending how this is interpreted ) This is going to be a coal Stoker stove, so there wont be any coals coming out the front as it will be automatic from the hopper.

 

[Danno77]

ok, gotchya. I'm only on beer two, so I'm only starting to think clearly (or is it the other way around).

Anyway, I'm not an inspector, nor do I claim to be, but I'm like 99% sure that an inspector wouldn't pass you unless you have that full 1.2 for a complete 16" out, and air space doesn't count unless it's UNDER the hardibacker and tile, which should be easy enough for you.

I guess I'm just making sure that you aren't putting the hardibacker with tiles directly on top of the perigo and counting the air space Above it as R-value.

I'm on beer three now and I'm snackish, which means that those beers went directly in on an empty stomach. I don't normally drink on a Sunday (or any other day, for that matter), but the mood struck me, and if I'm gonna do it, I'm gonna commit 100% to it.

 

[fph9999]

Hi, I have a similar set up.
I was wondering if the hearth pad needs to be permanent or can it be a removable pad as I would like to remove the pad during the summer.

 

[Danno77]

Hi, I have a similar set up.
I was wondering if the hearth pad needs to be permanent or can it be a removable pad as I would like to remove the pad during the summer.

I don't think it has to be permanent. Just keep in mind that if you ever sell the place, that some idiot may think it looks better without it and try to burn like that. That would be the only reason a permanent one would be safest. That seems like a lot of work to me!

 

[donnied44]

Ok, So now we've established that I need protection in front. I was hoping someone with experience with making a hearth pad would please give me the ingredients to establish a 1.2 R Value[/color]

I thought I had it covered earlier with the Hardiebacker until I read that chart and realizied it was only 0.26
Looks as though I'll have to find a hunk of granite and mount it to gypsum board. Does anyone else have any thoughts on the matter?

 

[donnied44]

Ok, So now we've established that I need protection in front. I was hoping someone with experience with making a hearth pad would please give me the ingredients to establish a 1.2 R Value[/color]

I thought I had it covered earlier with the Hardiebacker until I read that chart and realizied it was only 0.26
Looks as though I'll have to find a hunk of granite and mount it to gypsum board. Does anyone else have any thoughts on the matter?

I think I figured it out. After extensive research, I found out that I need to get a sheet of Micore 300. But from what I understand, it is hard to find locally. Will call Kamco Supply in the morning to see if they will sell me a sheet.

Thanks to all!

 

[Danno77]

if the hardibacker gets you 1/5 of the way there with each sheet, and the rest of the hearth is ok, then just make a slight frame on the front with enough space to put five sheets on top to make it flush with the rest of the hearth, then tile the whole sucker all uniform like and call it a day. because you don't have to make the front of the hearth out much further you could get by pretty cheaply, because you could be cutting strips out of each sheet to do it.

does that make sense? seems like the cheapest and easiest way to go.

 

[no stove yet]

(broken link removed to http://www.mantelsdirect.com/MC300-Micore-Board?ampcategory=304)

Hopefully the above link works for you,bad memory and all believe I got the link from someone here on hearth.

going thru the same things trying to figure out my hearth,trying not to have a large raised hearth coming into my living room.If I recall correctly the micore gives you r 1.1 and then durock .26,then tile and your good.

of course I know nothing don't even have a stove yet,but been reading all the posts I can to gain the knowledge,great source of info here.

Good luck with your setup.

 

[donnied44]

if the hardibacker gets you 1/5 of the way there with each sheet, and the rest of the hearth is ok, then just make a slight frame on the front with enough space to put five sheets on top to make it flush with the rest of the hearth, then tile the whole sucker all uniform like and call it a day. because you don't have to make the front of the hearth out much further you could get by pretty cheaply, because you could be cutting strips out of each sheet to do it.

does that make sense? seems like the cheapest and easiest way to go.

Yes it does make sense Danno. Thanks for the idea.

 

[donnied44]

http://www.mantelsdirect.com/MC300-Micore-Board?ampcategory=304

Hopefully the above link works for you,bad memory and all believe I got the link from someone here on hearth.

going thru the same things trying to figure out my hearth,trying not to have a large raised hearth coming into my living room.If I recall correctly the micore gives you r 1.1 and then durock .26,then tile and your good.

of course I know nothing don't even have a stove yet,but been reading all the posts I can to gain the knowledge,great source of info here.

Good luck with your setup.

Exactly, that is the beauty of this forum. I have been reading everything I could find here for the past 2 monthes to learn, and finally this weekend I bought a new stove. I figured what I didn't know I could find out between this forum, the nepacrossroads forum, and good ole Google. Everytime I posted a question here. almost everytime, the answer came back to me almost immediately. I really appreciate what everyone contributes here and hope to give back someday. Good luck to you and find yourself a nice stove that will work best for you.