How far can a fireplace insert stick out?

[Firefly1]

Good day everyone,

Total newbie, so bear with me. I want to purchase a wood fireplace insert for my home and have a few questions. Due to the way my fireplace is shaped the sidewalls taper in preventing me from placing the insert up against the back wall. I have read on the forums that this is okay to do and in fact several inserts have some adjustments for this type of application. The insert that I am looking to purchase is the Osburn 2400, even with the adjustment set at the minimum depth of 16 1/4 inches (411 mm) the insert would still stick out approximately 1/2-1 inch. How would i deal with this difference when I want to install the surround? And should I even proceed purchasing this insert knowing this issue. Should I purchase a smaller insert one that will fit in without any issues? My house is 2700 sq. ft. and and has cathedral ceilings and open floor plan and therefore would require an insert that will not struggle to keep up.

Another question is regarding the surround, the height of my fireplace open is approximately 40 inches none of the surrounds cover that much of an opening, what should i do? Many thanks for everyone's help!

 

[begreen]

Greetings. The gap is fine. It can be made up with a filler of aluminum L metal or square stock attached to the edge of the surround. A sheetmetal extension plate can be made and painted to match the surround to cover the upper gap. Or you can install the stove without a surround. On that idea you appear to have enough height to install a freestanding stove in the fireplace.

PS: Is this an interior or exterior chimney?

 

[Firefly1]

Hi Begreen, thanks for responding to my post. That's good to hear, so what you're saying is that gap can be filled by fabricating something to cover the difference. Is this a DIY project and where would I be able to get the material from? I am somewhat handy, but my experience is more with woodworking and electrical. If you install the stove without the surround, I am assuming this exposes the unfinished sides of the insert for viewing? Would that look awkward?

I thought about installing a freestanding stove in there, but I read some conflicting information here. The chimney is an exterior chimney and if I placed a stove in there 3/4 of the stove would sit inside the fireplace. I read that you loose a lot of heat through the back and sides and this would not be optimal given that it is an exterior chimney. Please correct me if I am wrong about this. Also, the way an insert is constructed you loose less heat through the back and sides as opposed to a free standing stove that's sitting in side the fireplace.

 

[bholler]

I read that you loose a lot of heat through the back and sides and this would not be optimal given that it is an exterior chimney. Please correct me if I am wrong about this. Also, the way an insert is constructed you loose less heat through the back and sides as opposed to a free standing stove that's sitting in side the fireplace.

That is how i see it but others dissagree. Regardless if the stove has a blower the difference will not be that much really. You can also insulate behind the stove to help with this.

 

[Firefly1]

Thank you Bholler for responding. Yeah, from everything that I read it seems some people think the heat loss is minimal to others who say that placing it inside the fireplace affects the performance drastically. So I'm kind of torn on what to do. Also aesthetically I'm not sure which would look better, having an exposed insert w/o any surround so you see the sides or wood stove with insulation on the sides. At this point I think I am leaning towards doing what Begreen said which is the insert and fabricating a custom surround. But please keep the advice coming, thanks!

 

[bholler]

Yeah, from everything that I read it seems some people think the heat loss is minimal to others who say that placing it inside the fireplace affects the performance drastically.

The way i see it you get more heat off of a freestanding stove in the open than an insert but when you put it in a firebox you loose that advantage and i feel you actually go the other way a bit. But honestly we are talking about small differences here if you want a stove in there go ahead and do it

 

[begreen]

For an exterior chimney fireplace installation of a freestanding stove you would do best with a convective stove unless it can be placed out on the hearth. At that point it is essentially very similar to an insert without the surround. To improve efficiency insulate the back and side walls for further heat loss reduction. Like an insert the more of the stove that projects out of the hearth the more radiant heat you will get off the stove.

An insert will also do the job and the Osburn is a good choice. It will have similar issues of the masonry stealing heat from the convective jacket. Exterior chimneys are simply poor design.

 

[Fastdonzi]

I'm kinda keen on doing a Block off plate to stop the heat from going up the chimney and getting as much to Radiate in to the room as possible.

 

[begreen]

A block off plate will primarily increase the heat convected by the insert. I suspect the heat radiated from the insert will be about the same.

 

[Firefly1]

Okay I feel more confident in my choice of the Osburn 2400 insert. I will definitely have a block off plate installed. So I have a few questions regarding the whole process of purchasing and installation:

1) At this point it appears I can get a better price by purchasing the Osburn 2400 insert online, plus the nearest dealer is about 40 miles away. So should I have someone install the insulated liner prior to delivery of the unit although it's probably much better to schedule the install after delivery so they can install the unit itself.

2) Do most installer's place a block off plate and is it part of the process or is that something that I specifically have to ask for? If they don't do it, is this something I can do after they place the insert in the fireplace?

3) Based on what I have read the best type of liner for an exterior chimney is: insulated, stainless steel. Does it matter if it's smooth?

4) Where should I go to have the metal piece fabricated for the gap between the Osburn's surround due to the insert protruding 1/2-1 inch more than what's recommended? And also for the gap in the top part of the surround due to my fireplaces height being greater than Osburn's surround?
a) Is this something I can do myself by purchasing the materials at a hardware store?

Sorry, all newbie questions but you guys have been really helpful and I don't want to screw this up Many thanks!!

 

[begreen]

If you are having the liner installed have the stove first so that they can measure and connect to it.
An insulated block off plate is an extra, you will need to request it.
Search on liner threads here, there are hundreds discussing this topic
A good local sheetmetal shop can handle cutting up the sheetmetal. If you could put your city and state in your avatar location that might help others connect you to local shops.

 

[Firefly1]

Thank you Begreen, will order first have the product on hand for installation. I just updated my location, live in Westchester County, NY. Anyone one have a general price reference for liner installation + insert install? And any recommendations for good sheet metal shop in my location, and what would something like this cost?

 

[begreen]

Maybe have a couple certified sweeps give a bid on the installation?
www.csia.org

 

[Firefly1]

Thanks for the link, will make a few calls and see what they come up with.

 

[begreen]

No problem, I grew up close by, many years ago.

 

[Firefly1]

That must have been a big change, I would move too but parents are old and don't want to be to far from them. Now you know why I'm asking about prices, everything seems to be always a lot more than what other people pay.

 

[Beer Belly]

Our Insert stick out 11 inches onto the Hearth, and our surround is 50 inches across.....we still needed to add the shield to the surround to meet code for the Mantel. We do have a Blower and a Block Off Plate. The issue we had with the stove being so far out on the Hearth were rfont clearances....we got around the code by throwing down a piece of Cement Board in front of it just to pass......not that I recommend anyone skirting code. My buddy built a Tiled Hearth Pad that he removes in the off season.

 

[Firefly1]

Our Insert stick out 11 inches onto the Hearth, and our surround is 50 inches across.....we still needed to add the shield to the surround to meet code for the Mantel. We do have a Blower and a Block Off Plate. The issue we had with the stove being so far out on the Hearth were rfont clearances....we got around the code by throwing down a piece of Cement Board in front of it just to pass......not that I recommend anyone skirting code. My buddy built a Tiled Hearth Pad that he removes in the off season.

Morning Beer Belly, thanks for posting and the visual. Our hearth is 30 inches and technically the wood stove has about 12 inches to extend before it doesn't meet code.I believe you need to have 18 inches clearance up front to meet code. We meet all other clearance requirements so I think we should be okay. Like yourself I will need to purchase the largest surround which I think for Osburn is also 50 inches across and 32 inches high. Our problem is that we will be almost 8 inches short on top. Would you mind telling me what insert you have, thank you.

 

[Beer Belly]

Morning Beer Belly, thanks for posting and the visual. Our hearth is 30 inches and technically the wood stove has about 12 inches to extend before it doesn't meet code.I believe you need to have 18 inches clearance up front to meet code. We meet all other clearance requirements so I think we should be okay. Like yourself I will need to purchase the largest surround which I think for Osburn is also 50 inches across and 32 inches high. Our problem is that we will be almost 8 inches short on top. Would you mind telling me what insert you have, thank you.

It's an Avalon Rainer....it's a small woodstove, but heats our 1,700 sq. ft home.....

 

[NYSB]

Firefly1,

I also live in Westchester County, NY and I agree everything seems to be more expensive... I had a local dealer install our Regency CI2600 last January - feel free to PM me for details. They did an OK job - this was before all my extensive reading on this and other websites so I didn't really know what questions to ask - nor the value of a block off plate or fully insulated liner. This is one of the larger inserts available and it easily fit into our existing very large masonry fireplace. We also had the problem that the stove surround did not cover the gap between the top of the insert and the top of the existing fireplace opening. We did not want any more black metal extending out from the stove. I attached some cement backer board over the existing brick surround, in preparation for the new ceramic tile surround. I simply put some hearth-friendly (not all are) cement backer board low enough to cover the anticipated gap and tiled over it. This way, we did not have to use the extra-extra large steel surround. The new front hearth extends 20 inches from the front, while the original slate hearth was 18" from the front of the old opening - so I needed a few extra inches of hearth extension (would have had right around 16" - borderline at best- with the new stove). I did this with layers of micore, cement backer board, medium set mortar and ceramic tiles. The wooden mantel and flashing I constructed myself, all with appropriate clearances. We were going for a contemporary look - rather than a more traditional "rustic" aesthetic.

The 23' chimney is external brick at one extreme end of our 1800' single-story house. It is a non-insulated liner and there is no block off plate - just some fiber insulation stuffed up into the bottom of the flue. At a minimum I plan to change the fiberglass (which is controversial in this application) to something more acceptable, like Roxul (mineral wool). Ideally I would also like to line the inside of the masonry fireplace, around the insert, with micore, install a block off plate, and upgrade to an insulated liner - I have not done any of this yet.

But even with this less-than-optimal installation the stove worked like gangbusters last season. Heated our entire house, no problem. I started off running it over the weekends, and then went to continuous operation for January, February, March. When I cleaned the chimney liner in April, I got about 1-2 cups of creosote. I think the insulated liner would certainly reduce creosote formation, although it does not seem to be a huge problem and I plan to clean the chimney once a year anyway.

We needed a permit in our neck of the woods, and when the inspector came to the house he was pretty impressed with the installation job, but clearly he is not an expert in hearth products... Our system may pass minimal code standards, but it is not optimal for performance. But, like I said, it works amazingly well as is.

This year I have 2.5 cords of Norway Maple and Red Oak mix; moisture content of a freshly split face at 13-15% right now.

Make sure you have an adequate supply of well-dried wood ready to go!

SB

 

[begreen]

Very nice job NYSB and a good solution Thanks for sharing.

 

[dafattkidd]

Hey firefly, Welcome to the forum. Something to consider: When installing your insert out on the hearth a bit beyond the recommended distance be aware of the height of you lintel, the location of the exhaust outlet on the unit and your ability to connect the unit to your liner. I have my osburn 2400i installed similarly to what you are explaining. My set up requires an offset box. My chimney is under 15 ft and with the offset box I have some draft issues. I'm not saying you will have the same problems, I'm just saying this is something to consider.

That said, the 2400 is a beast. It absolutely cranks out heat. The large firebox allows for great burn times, NS loading of logs over 20", EW loading of 23" logs. Mine protrudes into the room about 9" and pushes heat even without the fan running- if ever the power is out. I love this unit. There are certainly fancier looking units, but the 2400 is a true heat monster. Good luck!

 

[NJ_Burner08002]

I paid 500.00 for install in NJ.

 

[Firefly1]

Sorry folks for not responding sooner, was away for awhile and had to put out fires at work

Firefly1,

I also live in Westchester County, NY and I agree everything seems to be more expensive... I had a local dealer install our Regency CI2600 last January - feel free to PM me for details.

Love the clean modern look of your fireplace! I wish I could do something similar to our fireplace because we have a modern house, but our fireplace is brick and extends up to the cathedral ceiling another 7 feet. So I am not sure how I can tackle that. When you say, you tiled, did you completely tile over your existing brick facade?

 

[Firefly1]

Hey firefly, Welcome to the forum. Something to consider: When installing your insert out on the hearth a bit beyond the recommended distance be aware of the height of you lintel, the location of the exhaust outlet on the unit and your ability to connect the unit to your liner. I have my osburn 2400i installed similarly to what you are explaining. My set up requires an offset box. My chimney is under 15 ft and with the offset box I have some draft issues. I'm not saying you will have the same problems, I'm just saying this is something to consider.

That said, the 2400 is a beast. It absolutely cranks out heat. The large firebox allows for great burn times, NS loading of logs over 20", EW loading of 23" logs. Mine protrudes into the room about 9" and pushes heat even without the fan running- if ever the power is out. I love this unit. There are certainly fancier looking units, but the 2400 is a true heat monster. Good luck!

Thanks for the welcome!! I actually ended up ordering the Osburn 2400 insert earlier today, so I am excited to get it all set up. Thanks for the advice on the lintel, I think if I did my calculations correctly the lintel should be in the general area of the liner exhaust, but I will find out soon. I agree, although the Osburn looks fine, there are a lot of other better looking inserts (I particularly wanted something more modern/contemporary) but I felt I would be sacrificing form for function.