2 inch difference height between hearth and floor

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tathspts

Member
Jan 4, 2020
66
Montreal
I have this old masonary fireplace which I decided to buy wood insert for. I m buying drolet 1800-i and from the pictures it looks like the front of the insert does not sit flush with with the wall, but it protrudes outside a little bit.

My fireplace's hearth is 2 inch about the floor level, so it will make the drolet 1800-i over hang over the floor. I wonder if that is going to no big deal or I have to do something about it?

Maybe attached image will clear the picture I am trying to paint.
 

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You have to build a hearth that extends out onto the floor. Just think, you are loading the new stove, a spark jumps out and lands on the floor, at best you get a scorch mark on the floor. At worst, your house catches fire.
There are specs that come with the insert that say how far out the hearth must extend, but you want at least 16 inches. You can lay down a piece of 1/2 inch concrete board, and then put tile or flat rocks on it.
 
You have to build a hearth that extends out onto the floor. Just think, you are loading the new stove, a spark jumps out and lands on the floor, at best you get a scorch mark on the floor. At worst, your house catches fire.
There are specs that come with the insert that say how far out the hearth must extend, but you want at least 16 inches. You can lay down a piece of 1/2 inch concrete board, and then put tile or flat rocks on it.

as you can see in the picture I do have tiles in front of the hearth and they are indeed extended out to 16 inches, only thing is tiles are not at the same level of the hearth floor itself. I just wonder if that level different is going to be a trouble?
 
Not familiar with that stove. Looking at the picture, the protruding part is forward of the firebox. I would guess that the protruding part is a housing for the blower, and the legs (and the weight) are further back.

If it does turn out to be a problem, you'll just need some bricks and mortar and a saw to cut 'em up with.
 
Not familiar with that stove. Looking at the picture, the protruding part is forward of the firebox. I would guess that the protruding part is a housing for the blower, and the legs (and the weight) are further back.

If it does turn out to be a problem, you'll just need some bricks and mortar and a saw to cut 'em up with.

yes it is indeed blower. I thought about doing the same. Wasn't even going to use mortor. Just find some 2inch hight slabs or bricks at renodepot or something and put in there.

But I would imagine it is going to be fine, with it hanging in the air.
 
I think what Simon was referencing above was what does the manufacturer call for in terms of heat protection? If the tile is on top of the plywood subfloor, you may need to add a layer of fiberboard to meet the manufacturer,s specs. Not a big deal to resolve...I would think. Let's see if one of the chimney pros weigh in
 
I have read through the manual several times ( I thought about buying one but haven’t yet) It is not super clear clear about a hearth that is raised 0.1-5” above floor It is clear for the 5” and above, 16” from inert door with R>=1.49. For hearth level with floor it calls for R>=2 extending 29” ifront of the insert door.

so if i wanted to follow the manual I would make an extension that comes out 29” from the stove that has R greater than 2. And to make my life easy I would make it level, as I could, with the fire brick.



Evan
 

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Oops. I spaced that out. I thought the floor was wood.
As someone said, the tile might be OK, you need to see what is under it, might need an additional layer of fireproof material.
 
As I read the manual it's fairly clear. If the hearth is not at least 5" above the floor you need 29" of R=2.0. If 5" or more you need 16" of R=1.24. If you have the room I'd set the insert on pavers to raise it to the 5" then build a 16" extension to the proper r value. Its doubtful but you may already have it. It just a matter of determining what is under the tile. The last one I did was just a free standing hearth board that I built with micore and hardie board that just sat on the hearth. I used hi temp silicone to seal the gap between the board and the fireplace in case an ember fell in there.
 
As I read the manual it's fairly clear. If the hearth is not at least 5" above the floor you need 29" of R=2.0. If 5" or more you need 16" of R=1.24. If you have the room I'd set the insert on pavers to raise it to the 5" then build a 16" extension to the proper r value. Its doubtful but you may already have it. It just a matter of determining what is under the tile. The last one I did was just a free standing hearth board that I built with micore and hardie board that just sat on the hearth. I used hi temp silicone to seal the gap between the board and the fireplace in case an ember fell in there.

top of the tiles is flush with the floor level. I know tiles do not come as thick as hardwood floor. So there has to be something underneath the tiles. The problem is there is no way for me to find out what is directly underneath the tiles without taking one apart.

The way I it see it I might need to raise hearth level to 5inches by adding 3 inches material on hearth floor and then raise the area of the tiles by 5 inches to make it level with hearth floor and extend it 16 inches out, basically covering the whole tile area. What are my best choice of material for that.

I would be hiring a professional installer to install the stove. The one I had come take a look mentioned nothing about it. Makes me wonder why not.
 
Do you have a idea of how far out from the brick the door front will be?
 
You need to build floor protection with a r factor of 2.0 29" in front of the unit as is.
 
You need to build floor protection with a r factor of 2.0 29" in front of the unit as is.

I am thinking about it. Building floor protection might easier than raising the hearth floor itself.

Thinking about taking 2 by 4s and screw them onto the floor with 5 inch screws, put plywood on the top and them put some pretty tiles or bricks or something. Also thinking about building some sort of fireplace mantel.

I would love to get some ideas.
 
You may need a few layers of dura rock board to get to the 2.0 r rating, I'm pretty sure the 2.0 is needed due to radiant heating coming off the glass.
 
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I am thinking about it. Building floor protection might easier than raising the hearth floor itself.

Thinking about taking 2 by 4s and screw them onto the floor with 5 inch screws, put plywood on the top and them put some pretty tiles or bricks or something. Also thinking about building some sort of fireplace mantel.

I would love to get some ideas.
That won't get you to the required r value
 
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There are a dozen ways to make a hearth. No, make that 3 dozen.

Mine is a half inch of the concrete board, plus, two inches of flat rocks set in mortar, with home made frame of black walnut. It looks even better in person than in the picture.
Not sure what the R value is but it doesn't get warm, I have been running the stove all day and just felt the hearth, it is not even warm to the touch.

2 inch difference height between hearth and floor
 
Making a hearth extension for a masonry fireplace gets much more complicated if you are trying to strictly adhere to code. The easiest way around that is just make a board that technically isn't permanent. That way you just need to meet the r value for the stove not requirements for a fireplace
 
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Making a hearth extension for a masonry fireplace gets much more complicated if you are trying to strictly adhere to code. The easiest way around that is just make a board that technically isn't permanent. That way you just need to meet the r value for the stove not requirements for a fireplace

Can you please tell me what kind of board?

I kinda HAVE to follow the code, specially considering in case of any mishap.
 
Can you please tell me what kind of board?

I kinda HAVE to follow the code, specially considering in case of any mishap.
A price of plywood with cement board and or micore built up to the required r value and finished off with stone tile etc
 
If you build it yourself it will be a composite of materials stacked to get the required R value. Another option is to buy a premanufactured hearth extension board with the proper rating. There are many posts on this forum on hearth building. Try the search function.
 
so I was going through the installation manual and I noticed, I need R value of 1 not 2. Not sure how R value of 2 came into discussion. Please see attached.

Tiles in front of my hearth is 16 inches extended out, and in the manual it is mentioned the manual that I need 23 inches from the unit (did I read it right? ) If it have to be 23 inches, do I need to cut back the floor or I can simply put non combustible material over the floor?

I am thinking about raising the level of that tiles area to level of fireplace floor (2 inches of height) meeting the R value of 1 and then put a pad or something after those 16 inches to make it 23 inches in total. Am I going about it right?

I am going to have this thing installed professionally, the guy who will do it is on vacation in Florida. Purpose of this is to make sure I am I am well informed about it in advance, rather than having to deal with it later.

Thank you. Here is the link to installation manual for the unit I bought.
 

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Yes, you are correct, 23" r=1.0. That is a large hearth requirement. The r=1.0 hearth pad can sit on top of the existing hearth. That would be the simplest. This could be a challenge. Most hearth extension pads are 18" deep. 23" is an odd dimension so look for a 24" hearth extension pad. American Panel makes an octagonal one that is 24" x 32". If tiled, their type 2 hearth pad is 1.25" thick.

Hearth Pad pro sells one that is 24" x 36", but I don't know the R value and can't find a website for them

PS: I went to Energy King's website and it appears that their pads are ember protection only.
 
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Not sure how much room you have to work with but 23" seems like it would be pretty intrusive. I would see if you can raise the insert 3" with either pour in place concrete or pavers. Then you can build a 5" x 16" tall hearth extension that only needs to be non combustible. If it were me I'd remove the existing tile then reset new brick and tile to get 5". You could even build a stand alone extension.
 
Without dimensions its hard to say but maybe this is a good time to install a freestanding stove that needs only ember protection. By the time you add the expense to have a the hearth modified it would prob be a wash even if you can't stick with Drolet. Maybe cheaper.