Amy - quick answer on the chimney & then I'll get DH to walk me through the rest since the fireplaces are his balliwick.

The Georgian is a vented FP with a masonry look. There is a chimney out the roof, but it is framed from wood & will have our real stone veneer on it. We are doing the shroud so that it kinda has these 4 legs & then it will be capped with a slab of flagstone like we will have on the floor of our front terrace.

I'll see if I can get some pictures & get back to you.

The 42" fireplace with the ducting and labor was around $2800. I don't know about the framing & the cost of the stone will depend on the location because there are rules about height above the roof, etc. which are probably locale specific.

I'll let macv chime in, since he has a much greater depth of knowledge.

HTH - Jo Ann

Factory made gas fireplace units have type B gas vents through the wall or roof and wood burning fireplaces have chimneys which are either masonry (with a clay tile liner) or double-walled metal.

Building a 30 ft high exterior exposed masonry chimney requires a foundation, scaffolding and 2 or 3 workers to lift the masonry and mortar. The work slow and must be suitable for exposure to view and to the weather. Because of the load, a field built masonry firebox (or one built against a factory made steel frame) is normally used under such a chimney (although I suppose it's possible to somehow offset the load and use a metal firebox).

The alternative is to use a factory made metal fireplace (called zero clearance although it cannot be in contact with combustibles) with a double-walled metal chimney on top of it. (It could also be a masonry firebox with a metal chimney on top of it.) Where this chimney is exposed on a side wall or roof it can be enclosed in a wood structure and clad with a masonry veneer (4" masonry with a cavity between it and the sheathing), thin simulated masonry (adhered to sheathing), stucco on sheathing, EISF (thin synthetic stucco-like finish on extruded polystyrene insulation board on sheathing by Dryvit or STO, etc.), or masonry rendered (hand scored) on the face of stucco.

the sheathing might be preservative treated plywood (not OSB) or fiberglass reinforced concrete backerboard (not fiber-cement composite board. The work must be carefully detailed to avoid premature failure.

Mine is a Marco 41 prefab with a stone chimney, best of both worlds IMO. I didn't want a custom masonry FP cause nothing is built right nowadays. I normally use just the screen to block embers and allow max heat radiation because when I use the FP it's to heat the whole 1300 sf, then shift to just clear-view glass if it's getting a little too warm. Tip: Hardwoods burn much hotter and slower, but are more difficult to start. I recommend at least a 40" wide unit for max viewing pleasure. (Thanks Macv for the Tinypic instructions)

http://www.fmiproducts.com/ is the maker of the Georgian. We have the Windsor (see through between rooms). FMI offers a brick look to the firebox, wood and gas rated, and exterior versions. They even have a modular masonry one for exterior.

Our local installer had a very good price, better than I could get going online.

macv - DH saw the pictures you posted and asked if you could give us some more details on how that chimney was finished. That is exactly what he wants it to look like. (It's the house you designed for your brother, right?)

Unfortunately, the best picture I have of the current state of our chimney isn't that good, because that wasn't what I was trying to capture:

We'd value and appreciate any advice you can give us.

Thanks - Jo Ann

This info is priceless! Printed out the whole thread. Thanks.

Since most "zero clearance" factory built metal fireplaces are limited in height to about 29" (often less) I prefer the 36" width so the proportion of the opening is closer to a traditional one. As with most design issues proportion is more critical than any one dimension.

My Colonial Revival house was designed by a major Boston architectural firm in 1891. The fireplaces are sized as follows:
Living Room 25 h x 30 w - ratio 1.2(moved in 1903 with Victorian green ceramic tile surround)
Dining Room 31 h x 36 w - ratio 1.16 (brown iron spot brick surround)
Master Bedroom 30 h x 30 w - ratio 1.0 (dark red brick surround)
Front Parlor 30 h x 36 w - ratio 1.2 (gas fireplace added in 1903 by the architect with marble surround cast metal liner, gas supply & metal vent to roof.

All I know about the imitative stone chimney enclosure is what you see in the photos. The contractor did not opt to use my design and never told me what was done.

Since the factory chimney has a large spark arrestor cap (see photo of exposed chimney from another job) I wanted the cap to extend above the top of the imitative enclosure in order to avoid the possibility of sparks/embers being trapped inside the enclosure. I suspect the arrestor cap wasn't even installed. This is the project where I was forced to ask for my stamp to be removed from the drawings.

The enclosure bottom should be allowed to drain onto the roof shingles since the metal chimney already has a large factory made flashing cone fully flashed into the roofing shingles and the imitative stone enclosure is only a cosmetic screen. Be careful to not trap water. Get a contractor who has done this before and look at the aged results. Make the imitative masonry corners as convincing as possible if the chimney starts at the ground. I believe there are composite imitative stone systems that actually wrap the corners. But most people have forgotten what real masonry corners look like so it might not matter. And the contractor probably won't build it the way it's designed anyway.

Thanks for all of the great information so far! Would it complicate matters if I told you that I don't want a built up hearth? Can the firebox be "sunk" into the floor so that the floor of the box is even with the living room floor? Maybe it sounds primitive but I love how I can sweep stuff directly into the fireplace in our little rental house.

macv - Thanks, so much for the reply. Well, with the 42" x 30" opening, our ratio is 1.4. If we had gone with the 36" opening, we would have hit 1.2 on the head. I know I should have paid more attention to previous discussions on fireplace proportion. darn.

All of the imitative stone chimney enclosure is above the roof surface on the rear of the house. I think only one neighbor will have any kind of view of it during the winter when the leaves are down. Due to the slope of the lot from the road to the house, only the very top is visible from the road which is why we want this to have a nice treatment like the one you showed in the picture.

I just talked to DH and he & the fireplace guy have come to a mutually agreeable to solution to trade some aesthetics for avoiding potential water issues. He said that he would write that up for me so I can post it.

The corners won't be visible at ground level. However, we are using the same real stone thin veneer which will be at "foundation" level below the Nichiha shakes. DH says that there are corners for it.

I know you were upset when you had to have your stamp removed from that project, so I'm sorry if I stirred up unpleasant memories. However, thank you so much for the insight. It really helps.

Jo Ann

Jo Ann, it gets stirred up every time I see my brother-in-law so I'm used to it. The kitchen island that the contractor made a foot too narrow bothers me more. I could go on.

Amy, the floor of metal fire box is constructed to be about 2 inches off of a combustible floor. If you want to have the floor of the firebox flush with the finish flooring of the room (a nice feature IMHO), you need to cut the top the floor framing down the appropriate amount and to make sure that there is still the proper clearance to combustibles which generally means leaving an air space or using a non-combustible material where adjacent to or in contact with the unit (ie the material immediately under the hearth at the fireplace).

In other words, you need to make a floor depression to accommodate the unit and the required non-combustible hearth extension and use layers of concrete board or a mortar bed under the hearth so there is nothing combustible touching the front lower lip of the firebox.

Amy - I'm reposting the picture of our woodburning fireplace after it was framed in:

DH chose this fireplace because it has a "clean face" which means that there won't be any black metal showing. The refractory liner is simulated brick and looks very nice. There is another version with a grid in which you set thin "brick" and then use a refractory mortar so it looks very realistic. We figured that once a few wood fires were made in the FP, the difference between the two would not be that noticeable.

There is the FMI Plantation series which can be flush to the floor without having to sink it. It does cost more than the Georgian. If you are doing a raised hearth, you won't see the metal strip, anyway. We are doing a flush hearth and just accepting that we will cover that lower black strip with a non-combustible and it won't look as realistic.

HTH - Jo Ann

Here is a link that might be useful: FMI Georgian

The FMI Plantation has a 1 3/4" thick base that can be installed on a non-combustible floor. To be installed on a combustible floor a 4 3/4" thick spacer kit is required making the firebox floor 6 1/2" above the subfloor. Either way it must be recessed into the subfloor to be flush.

The 48" Plantation is the largest fireplace I have seen with a traditional proportion (ht = 42"). I like it.

FMI also offers a masonry liner system.

I often use the Lennox Colonial 36 which has a 7" base.

Here is a link that might be useful: Lennox Colonial

macv - sorry for my misinformation wrt the Plantation. I don't always get what DH tells me straight (and don't y'all ever tell him that I admitted to that. LOL!)

DH really liked the Plantation, or the better liner system for the Georgian, but one does have to trade aesthetics for budget, at times. (sigh)

We strongly considered some kind of hand glazed at tile for the surround. dang budget. Your living room FP sounds divine. The slate we are using is inexpensive enough, that we might consider upgrading to tile in the future.

Jo Ann

FMI claims their Plantation fireplace can be flush with the floor and doesn't mention the non-combustible requirement; you have to look at the installation instructions. Learning the features of this systems requires a lot of work but the internet has made it much easier.

Macv,
Assuming all of the non-conbustible requirements are met, can the Lennox Colonial be "sunk" in the floor or would the FMI Georgian be better? I think the Plantation is way too big for us. I really wanted a 36 inch one that is as square as possible. What do you think the best model is that can be installed flush? Thanks.
Amy

All of the factory made wood fireplaces have to meet the same UL test requirements so they all have to be sunk a similar amount into the floor and everything higher than that subfloor and within 2 +/- inches (read the instructions carefully for clearances on each side) of the unit would have to be non-combustible or an air space on all sides ... and the hearth would have a non-combustible surface. It's not difficult to understand, the metal box is designed to not heat wood to the ignition point and it does that with sheetmetal and air spaces inside the unit and air spaces or non-combustible materials outside the unit.

Most of the manufacturers now offer a 36" wide X 30"+/- high opening. Some have retractable screens and nicer fire brick liners. I like the Lennox only because they were one of the first to make an opening higher than 25 inches and provide an outside air kit.

I see the advantage of having a taller opening. I can't stack too many large diameter logs as it is. I can't resist the chance to promote no-frame glass doors....maximum view, no cheesy brass trim that discolors. OK, I'll stop now.