Non-Combustible Requirement for raised Hearth?

[paredown]

I was wondering about the requirements if your hearth is raised.

Code says:
"§R1001.10 Hearth extension dimensions. Hearth extensions shall extend at least 16 inches (406 mm) in front of and at least 8 inches (203 mm) beyond each side of the fireplace opening. Where the fireplace opening is 6 square feet (0.557 m2) or larger, the hearth extension shall extend at least 20 inches (508 mm) in front of and at least 12 inches (305 mm) beyond each side of the fireplace opening."

We have a large raised firebox fireplace, (fieldstone) with a long raised floating hearth extension--a continuous slab of stone about 16" wide--pinned and mortared in place. The wood flooring runs up to the fieldstone face.

If we flush mount an insert, will the existing floating hearth meet the requirement?

If we use an insert that extends onto the floating hearth, do we need to add a deeper non-combustible pad underneath where the insert sits?

 

[Summertime]

What size is your fireplace opening? I would think that if your hearth is the required size and has been built on non-combustible material it would be fine, It would help if you included a picture of your fireplace to better understand your situation. You will also have to find out what stove you will consider and check to make sure that all clearances are met including the hearth and mantel.

 

[paredown]

Picture is worth a 1000 words--sorry it's not better, but the FP is covered in construction materials at present.

-Fire place is 63” wide x 30” high by ~24” deep.
-masonry firebox, rough fieldstone facing floor to ceiling with a wide (& long) raised hearth--about 16” deep
-internal single floor chimney (<25 feet as a guess)--sits between the great room area and master bedroom wing.
-the chimney has a single round flue that is about 24” across & the damper ledge may allow the 6” pipe to clear without a problem

I've been going back and forth on insert vs stove--last spring a couple of folks were encouraging me to go with the stove set into the opening.

But back to the original question, if I extend out onto the hearth extension (say with a regency hearth heater), will I need non-combustible material below it?

 

[begreen]

Not an expert here, but I think the answer is yes. However, air is a good insulator, and that should be taken into account for the floor hearth extension R value.

From the looks of this image, this is a big space. It looks like it is going to take a hefty heater to fulfill its needs. How many sq ft are you intending to heat with the stove?

 

[paredown]

The house is a 60s contemporary single floor--sort of three boxes; great room in the center (in the picture), kids wing off one end of this; the master bedroom wing off the other at right angles.

We want a stove as supplemental (but probably main?) heat in this “great room” area (lr/dr/kitchen/entrance)--it's close to 1400 sf, high peaked ceiling post and beam with lots of single pane glass. Open plan, so no full walls. Not sure how you would direct the heat to the kids end, since the house is so long. Master suite should warm up nice though since it backs onto this chimney.

Last spring I was excited by the Clydesdale insert; other folks were encouraging me to consider a stove set in to the firebox because it is so large.

Now the budget is smaller so I'm looking at stoves as a lower cost alternative.

 

[begreen]

Yes, fall is not the best time for bargains. I'd get a 3 cu ft stove and put a ceiling fan in.

 

[paredown]

One of the members on this forum, Sleepy, has some clearance new Quadrafire Cumberlands, since his company is getting out of the business. Only a 2.4 cu. ft firebox, but the sideload would be nice if we set it into the fireplace a little. And you can add a blower to them.

Alternatives I have seen local (used) are inserts--Quadrafire 4100i; Avalon Rainier (light use on this one--it looks pretty nice).

I'm a bit worried about buying used since I know nothing except what I've gleaned from this forum and manufacturers' websites.