Front floor clearance for stove on a raised hearth

[Nick Mystic]

I recently installed a Jotul F 600 in front of my fireplace on a hearth extension that is raised nine inches above my floor level. Here is a photo:


The hearth extension extends 17" from the fireplace and the stove front sits just two inches from the front edge. I plan to do all my loading through the side door and do not plan on ever opening the front doors while burning. I'll only open the front doors on occasion to clean the glass when the stove is cold. My floor is a floating laminate that is made of a combustible material (although it is fairly hard to catch fire). Presently, I just have the hearth rug in front of the stove that I used with my old insert. It protects against embers. With this arrangement I'm not sure what my requirement is for clearance in front of the stove. I've read in multiple threads here at the forum that stoves on raised hearths meet the 16" front clearance requirement by being on the raised hearth and only need ember protection out front. Is this true, or do I actually need to put down a fireproof pad of some sort in front of my hearth extension. I'm not too concerned about the actual safety since there is no chance of something hot falling out the front and my side door has about five feet of brick in front of it.

 

[Crane Stoves]

18 inches from the main body of the unit (not the front edge of the ash lip) to the nearest combustible material. The floor you have appears to be Lino tiles which are a combustible material, but even if you had ceramic tile it would be considered combustible because of the wood under it.)

I should say... you need to make your hearth extend min 18 " out from the front body of the stove to meet most inspectors guidelines.

 

[tigeroak]

Our insurance company would have you go out in front what it says in your book for the combustible floor. While you say you will never use the front load, it is there and you must prepare for that out front. If you would have a fire you would not be covered. Our insurance company said 25 inches in the front and we made it 27 inches. Like I said that is here, your insurance company and state my be different.

 

[Eaglecraft]

I recently installed a Jotul F 600 in front of my fireplace on a hearth extension that is raised nine inches above my floor level. Here is a photo:

View attachment 96526
The hearth extension extends 17" from the fireplace and the stove front sits just two inches from the front edge. I plan to do all my loading through the side door and do not plan on ever opening the front doors while burning. I'll only open the front doors on occasion to clean the glass when the stove is cold. My floor is a floating laminate that is made of a combustible material (although it is fairly hard to catch fire). Presently, I just have the hearth rug in front of the stove that I used with my old insert. It protects against embers. With this arrangement I'm not sure what my requirement is for clearance in front of the stove. I've read in multiple threads here at the forum that stoves on raised hearths meet the 16" front clearance requirement by being on the raised hearth and only need ember protection out front. Is this true, or do I actually need to put down a fireproof pad of some sort in front of my hearth extension. I'm not too concerned about the actual safety since there is no chance of something hot falling out the front and my side door has about five feet of brick in front of it.

From a previous post last year:

The International Residential Code (the IRC) 2009 edition, does address the raised hearth issue in that allows a reduction in the thickness of the hearth extension. Also, the IRC addresses the Hearth Extensions of Fireplace Stoves. Here are the pertinent sections:

Chapter 10, Chimneys and Fireplaces, Section R1001, Masonry Fireplaces, Page 448, IRC, R1001.9 Hearth and Hearth extensions: Masonry fireplace hearths and hearth extensions shall be constructed of concrete or masonry, supported by noncombustible materials, and reinforced to carry their own weight and all imposed loads. No combustible material shall remain against the underside of hearths and hearth extensions after construction.

R1001.9.1 Hearth thickness. The minimum thickness of fireplace hearths shall be 4 inches (102mm).

R1001.9.2 Hearth extension thickness. The minimum thickness of hearth extensions shall be 2 inches (51mm).

Exception: When the bottom of the firebox opening is raised at least 8 inches (203mm) above the top of the hearth extension, a hearth extension of not less than 3/8 inch-thick (10mm) brick, stone, tile or other approves noncombustible material is permitted.

R1001.10 Hearth extension dimensions. Hearth extensions shall extend at least 16 inches (406mm) in front of and at least 8 inches (203mm) beyond each side of the fireplace opening. Where the fireplace opening is 6 square feet (0.6m squared) or larger, the hearth extension shall extend at least 20 inches (508 mm) in front of and at least 12 inches (305mm) beyond each side of the fireplace opening.

And finally, on page 486, Section 1414 Fireplace stoves

M1414.1 General. Fireplace stoves shall be listed, labeled, and installed in accordance with the terms of the listing. Fireplace stoves shall be tested in accordance with UL 737.

M1414.2 Hearth Extensions. Hearth extensions for fireplace stoves shall be installed in accordance with the listing of the fireplace stove. The supporting structure for a heart extension for a fireplace stove shall be at the same level as the supporting structure for the fireplace unit. The hearth extension shall be readily distinguishable from the surrounding floor area.

My take on the above code requirements is that for a raised hearth installation, the thickness of the hearth extension can be reduced to 3/8 of an inch. That's probably the total thickness of ceramic tile (or other noncombustible material) set in a bed of mortar. But the size of the hearth extension is not reduced to less than 16 inches on account of a raised hearth. Also the Code makes clear that the woodstove must be installed according to the manufactures' UL listing requirements.

 

[KaptJaq]

The manual states:

In the U.S. and Canada
The Jøtul F 600 must be installed on a non-combustible surface
extending:
A minimum of 18” (460mm) in front of the stove and the right
side load door (measured from the legs).
And 8” (200mm) on the left side and back of the stove (measured
from side and back panels).
Floor protection under the stove must be constructed of a non-
combustible material for protection from radiant heat, sparks,
and embers.
Individual sections of floor protection must be mortared together
to prevent sparks from falling through to combustible materials.


It looks like you need 18" in front of the stove and it needs to be a solid piece. No seams that go through to combustible material, no rugs.

The manual mentions that the side must also extend 18" from the door. If you have less that 18" the side door lock kit must be installed. From this I would assume that if you don't have the pad 18" in front you must lock the door to make it comply to the installation instructions. Saying you are not going to use it doesn't count.

With the front of the stove so close to the edge of the hearth and the opening edge of the side door at the front there is always the possibility that hot embers can fall out of the side door and tumble onto the combustible floor material. I would consider laying some ceramic tile at floor level to extend the hearth to the specifications listed in the manual.


KaptJaq

 

[Tom Cat]

The manual states:

In the U.S. and Canada
The Jøtul F 600 must be installed on a non-combustible surface
extending:
A minimum of 18” (460mm) in front of the stove and the right
side load door (measured from the legs).
And 8” (200mm) on the left side and back of the stove (measured
from side and back panels).
Floor protection under the stove must be constructed of a non-
combustible material for protection from radiant heat, sparks,
and embers.
Individual sections of floor protection must be mortared together
to prevent sparks from falling through to combustible materials.


It looks like you need 18" in front of the stove and it needs to be a solid piece. No seams that go through to combustible material, no rugs.

The manual mentions that the side must also extend 18" from the door. If you have less that 18" the side door lock kit must be installed. From this I would assume that if you don't have the pad 18" in front you must lock the door to make it comply to the installation instructions. Saying you are not going to use it doesn't count.

With the front of the stove so close to the edge of the hearth and the opening edge of the side door at the front there is always the possibility that hot embers can fall out of the side door and tumble onto the combustible floor material. I would consider laying some ceramic tile at floor level to extend the hearth to the specifications listed in the manual.


KaptJaq

I'm new to this and have found the floor protection requirements hard to decipher in some manuals. The manual says protection from radiant heat, which I would think implies an R value for the floor protection.

Tom

 

[tickbitty]

Would a hearth extender/pad work here? Seems a simple solution. But not sure whether it works for your requirements. http://www.woodlanddirect.com/Wood-..._a2s_2140412&gclid=CNC33ZyA9rUCFaUWMgodpmIAUw

http://www.efireplacestore.com/cpf-73900.html

 

[KaptJaq]

I'm new to this and have found the floor protection requirements hard to decipher in some manuals. The manual says protection from radiant heat, which I would think implies an R value for the floor protection.

Tom

Tom

I believe the F 600 needs a Type I ember protection hearth pad. The manual refers to thermal protection but does not give any R value. Several sites that make custom hearth pads sell a Type I pad for the F 600. You should be able to confirm this with your Jotul dealer. The F 600 Jotul manual looks like a cut & paste job from several earlier manuals that should have been reviewed before it was published.

KaptJaq

 

[Crane Stoves]

From a previous post last year:

The International Residential Code (the IRC) 2009 edition, does address the raised hearth issue in that allows a reduction in the thickness of the hearth extension. Also, the IRC addresses the Hearth Extensions of Fireplace Stoves. Here are the pertinent sections:

Chapter 10, Chimneys and Fireplaces, Section R1001, Masonry Fireplaces, Page 448, IRC, R1001.9 Hearth and Hearth extensions: Masonry fireplace hearths and hearth extensions shall be constructed of concrete or masonry, supported by noncombustible materials, and reinforced to carry their own weight and all imposed loads. No combustible material shall remain against the underside of hearths and hearth extensions after construction.

R1001.9.1 Hearth thickness. The minimum thickness of fireplace hearths shall be 4 inches (102mm).

R1001.9.2 Hearth extension thickness. The minimum thickness of hearth extensions shall be 2 inches (51mm).

Exception: When the bottom of the firebox opening is raised at least 8 inches (203mm) above the top of the hearth extension, a hearth extension of not less than 3/8 inch-thick (10mm) brick, stone, tile or other approves noncombustible material is permitted.

R1001.10 Hearth extension dimensions. Hearth extensions shall extend at least 16 inches (406mm) in front of and at least 8 inches (203mm) beyond each side of the fireplace opening. Where the fireplace opening is 6 square feet (0.6m squared) or larger, the hearth extension shall extend at least 20 inches (508 mm) in front of and at least 12 inches (305mm) beyond each side of the fireplace opening.

And finally, on page 486, Section 1414 Fireplace stoves

M1414.1 General. Fireplace stoves shall be listed, labeled, and installed in accordance with the terms of the listing. Fireplace stoves shall be tested in accordance with UL 737.

M1414.2 Hearth Extensions. Hearth extensions for fireplace stoves shall be installed in accordance with the listing of the fireplace stove. The supporting structure for a heart extension for a fireplace stove shall be at the same level as the supporting structure for the fireplace unit. The hearth extension shall be readily distinguishable from the surrounding floor area.

My take on the above code requirements is that for a raised hearth installation, the thickness of the hearth extension can be reduced to 3/8 of an inch. That's probably the total thickness of ceramic tile (or other noncombustible material) set in a bed of mortar. But the size of the hearth extension is not reduced to less than 16 inches on account of a raised hearth. Also the Code makes clear that the woodstove must be installed according to the manufactures' UL listing requirements.

The main key here is "General. Fireplace stoves shall be listed, labeled, and installed in accordance with the terms of the listing."... This is why its important for an owner of an old stove to have the original clearances dictated by the stove manufacturer (this info was typically not printed on the stove itself other then a U/L label (the information would be available with the testing lab and in the manual for the stove). The problem is sometimes the Label on an old stove is gone or UN-readable and the manual for a specific stove is also not available or in some cases when the U/L lab had a fire in Maine decades ago many records were lost forever (in this case that stove cannot be installed legally, at least in my area). Having said that... most U/L listed stoves from 1970-1990 had a similar 18" clearance from the front of the stove to the nearest combustible material.

Kinda ironic the U/L had a fire LOL (dont mean to laugh but you have to admit its a lil' humorous)

 

[TradEddie]

I have an almost identical situation so I bought a hearth extension online, it cost a fraction of what the local dealers were asking, look up my post from this time last year for details if you want. I didn’t need any inspections so I can’t say it meets requirements, but if an inspector had a concern I’d show him the section of code above that makes allowances for a raised hearth. You’ll have lots of radiant heat from that front window, best to make sure it’s not heating anything combustible.

TE