what to do with a fireplace? --how much heat loss with insulated liner connected to stove?

[rmcfall]

So my wife and I are going to be closing on a new house soon and I am wondering about the best placement for a woodstove. For those who replied to some earlier posts of mine, the house we decided on is a different one than I described before. This one is much better suited for a woodstove as it has a much more open floorplan. Anyway, this new house has a large family room with vaulted ceilings and a brick wall (unfortunately, the brick is painted right now) that divides the family room from the kitchen/dining area. Along the brick wall seems like it would be a great placement for a stove since it is an interior wall and the stove pipe could run straight up and go through the vaulted ceiling. In the same room, however, there is also a large fireplace. A stove would also look great on the hearth of this fireplace, but it is on an exterior wall. Thus, while I've got a great place for the stove sitting in front of the brick wall, it is sort of a shame not to utilize the fireplace. Any creative ideas for what to do with the fireplace if the stove is placed along the mentioned brick wall? Or do I use the fireplace and insulate the chimney the best I can?

 

[rmcfall]

That is a good thought. I guess I just prefer the looks of a stove and like the idea of the stove pipe running up through the vaulted ceiling. Perhaps I will have to get over that though, as an insert does seem like it would make sense in this case.

 

[zogboy]

That is a good thought. I guess I just prefer the looks of a stove and like the idea of the stove pipe running up through the vaulted ceiling. Perhaps I will have to get over that though, as an insert does seem like it would make sense in this case.

Maybe your fireplace was built to serve.
Have it checked out , you may just have a
real peach or at least be able to convert it to a masonary heater.

 

[Rhone]

Boy, that's a tough configuration. There are 2 places I believe are poor choices for inserts & stoves if trying to heat your house, and not just the room it's in. The kitchen is one as having one there while cooking, the combo of the kitchen stove and wood stove can make it unbearable. The second is rooms with Cathedral/vaulted ceilings as the heated air rises to the top of them and gets trapped. Rooms without them, the heat moves freely to other parts of your house. Ceiling fans you either love or hate. You have to think about the air pattern of turning them on in the room as they can cause a situation where the air rises up to the ceiling fan, gets pushed back to the floor and circles around back to the ceiling fan basically evening out all the heat into that room and preventing much heat flow out of it. Some find without the ceiling fans on, the heated air will eventually start to spill over to other rooms and flow around the house better than with them on. A freestanding stove against the brick wall I think is a better option if you want it in that room. It has radiant heat, which isnt affected by vaulted ceilings. It will warm up the masonary wall inside which will continue to release subtle radiant heat for many hours and if the wall is thin enough radiate heat on the other side. An insert you need to analyze air flow, as an insert makes almost strictly hot air, more than a freestanding stove. You don't want it say, blowing out hot air that rises to the top of these ceilings where it cools on the far side, drops to the floor where it's sucked back into the insert and repeats. So my vote is with a difficult configuration like that a freestanding stove against the brick wall with the stove pipe running up is probably going to be your best bet whether just trying to heat that one room, or your house (which you'll most likely need a little help with registers or/and small fans to overcome the vaulted ceiling. I see it all the time people add registers or small fans and even with stoves/inserts with those ceilings they heat their house).

 

[rmcfall]

I knew the cathedral ceilings might pose some difficulty, but I didn't realize it would be such a tough configuration. Perhaps since the family room with the vaulted ceilings is connected to the kitchen and dining room via an enlarged opening (about a 12 foot wide opening) as opposed to a regular doorway, the heat transfer out of the family room will be better? Plus, I plan on removing most, if not all, of the wall that divides the kitchen and dining room, which I imagine should help as well.

Those registers you are referring to--are they at ceiling level and include a fan operated via a thermostat?

Boy, that's a tough configuration. There are 2 places I believe are poor choices for inserts & stoves if trying to heat your house, and not just the room it's in. The kitchen is one as having one there while cooking, the combo of the kitchen stove and wood stove can make it unbearable. The second is rooms with Cathedral/vaulted ceilings as the heated air rises to the top of them and gets trapped. Rooms without them, the heat moves freely to other parts of your house. Ceiling fans you either love or hate. You have to think about the air pattern of turning them on in the room as they can cause a situation where the air rises up to the ceiling fan, gets pushed back to the floor and circles around back to the ceiling fan basically evening out all the heat into that room and preventing much heat flow out of it. Some find without the ceiling fans on, the heated air will eventually start to spill over to other rooms and flow around the house better than with them on. A freestanding stove against the brick wall I think is a better option if you want it in that room. It has radiant heat, which isnt affected by vaulted ceilings. It will warm up the masonary wall inside which will continue to release subtle radiant heat for many hours and if the wall is thin enough radiate heat on the other side. An insert you need to analyze air flow, as an insert makes almost strictly hot air, more than a freestanding stove. You don't want it say, blowing out hot air that rises to the top of these ceilings where it cools on the far side, drops to the floor where it's sucked back into the insert and repeats. So my vote is with a difficult configuration like that a freestanding stove against the brick wall with the stove pipe running up is probably going to be your best bet whether just trying to heat that one room, or your house (which you'll most likely need a little help with registers or/and small fans to overcome the vaulted ceiling. I see it all the time people add registers or small fans and even with stoves/inserts with those ceilings they heat their house).

 

[rmcfall]

I've been thinking more and more about the fireplace and how it is a shame not to use it since it is the focal point of the room. Plus, it seems a little odd to me to have both a fireplace and freestanding stove in the same room. So what I am wondering is, if I were to place the stove on the fireplace hearth and insulate the liner running up the chimney (the fireplace/chimney is on an exterior wall), how much of a sub-optimal setup would that be compared to having the stove vented directly through the vaulted ceiling at an interior wall? In a previous house my stove liner ran up an insulated chimney along an exterior wall and I had no draft or creosote issues whatsoever. Of course, I have never operated a stove that was on an interior wall, so I have nothing to compare. Is there a significant amount of heat loss by being vented through a chimney at an exterior wall? Is a lot of heat that would be felt from the exposed stovepipe of a freestanding stove lost in a hearth mount setup? Please help. Any ideas/suggestions are appreciated.

 

[Mo Heat]

r,

It's debatable whether it's even a good idea to extract much heat from an internal chimney to warm the room. Some folks argue double wall should be used from flue collar to ceiling to keep creosote accumulation to a minimum, especially with tall flues.

If you insulate a SS liner inside the masonry chimney, you will probably have adequate draft once the fire is started. The only drawback might be an initial negative (down) draft that would be easily reversed before kindling. And I find this is only the case if I had no fire at all the previous day. Even a fire the day before prevents this in my external masonry chimney. And mine is not insulated. But I'm in Missouri and not subject to extreme cold (20's and 30's mostly). To me, this indicates some heat loss to the masonry, but how much is hard to say.

I'd think the bigger potential loss of usable heat would be to the external masonry in general, but it is hard to actually notice in my house, although I'm sure it's there, but this will occur even if you place your stove at a distance. Of course, if it's closer, you'd have a greater heat differential, and likely more loss theoretically, but practically, it's hard to determine, or even notice, what is actually going on.

If you're not going to put the stove 'inside' the fireplace (insert) and it sits out on the hearth, heat loss to the masonry may be minimal, especially if you place a facade over the fireplace opening and insulate behind the facade. If it's one of those really big, shallow, open type fireplaces, and the stove is going to sit mostly inside, you may lose some heat there since insulation may be out of the question, but it would probably look pretty cool. A convection shroud and blower would probably be good in this situation, but may not be best with your cathedral ceiling.

If you decided to go with a typical insert that fits inside the masonry fireplace opening, you can also insulate around the inside of the fireplace with a ceramic blanket. If you install a block-off plate with some insulation either stuck to it or on top of it, then you'll have insulated all surfaces save the bottom upon which the insert sits. If you had enough space, you could even add a cement board or two (not sure how that would look, but maybe you could add some trim down there), and possibly a shiny steel sheet to block substantial heat from going downwards as well. All extra work, but possibilities.

 

[rmcfall]

Mo Heat-

Thanks for the response and the information about heat loss (or relative lack of) with liners running up masonry chimneys on exterior walls. From what you say and what another recent thread talks about with regard to freestanding stoves, it really sounds like heat gain from exposed stovepipe is minimal since double wall pipe is recommended. Thus, since an insulated exterior chimney won't result in much noticeable heat loss, using the existing fireplace in our home probably makes the most sense. Without much trouble I will be able to set the stove out on the hearth after redoing it to make it deeper, and then rear vent the stove into the chimney via an insualted liner.

Rob

 

[Rhone]

I think what you said, a freestanding stove sitting on the hearth with the vaulted ceilings, and view is going to work best.

To do it properly, you should seal off the fireplace opening with a surround. Take a look at some photo's of a hearth mount stove http://www.hearthstonestoves.com/wood_stoves/homestead/photos.shtml in particular notice how they closed off the opening of the fireplace? I show you this one, because it's designed to fit on a hearth and in the photo's show people who've closed off their fireplace openings. The bottom is the picture I like, that's the stoves optional kit to cover your opening. This stove is extra narrow to fit on hearths, and wide and tall intead. I can't recall if it's big enough though for your house, but I recommend something to close it off. I prefer closing the opening with a metal one as it can be removed later.

For some tips for considering the layout of your room, stoves produce radiant heat that comes off from the sides and based on how big the side is. Approach a big side, you'll feel more than approaching a smaller side of the stove. What I mean by nearly straight out, if you approach a stove directly from any side, you'll feel the radiant heat get warmer & warmer. However, you approach a stove diagonally and you will feel practically no radiant heat as you walk up to it and can stand diagonally to it no problem. Doing so directly against a side while the stove is roaring, is a different story. That should help you with furniture arrangements and explain some things like the seat directly in front is always going to be a hot seat, those diagonal to the stove will have very little radiant heat , and if you have seats on the sides of the stove, if those sides are big they to will be hot seats as well. If you want equal amounts of radiant heat all around the stove, you need a round stove. Steel puts out more radiant heat than cast iron, cast iron more than soapstone. If you're afraid of roasting yourself out of the room, you're probably better with a soapstone stove, the problem with soapstone is they work differently than steel or cast iron one's and you'd need to understand the difference and how they heat and operate.

Registers, wait until you see how it goes before putting them in. I'm of the reverse school, that is instead of thinking how can you move the heat out to other rooms, instead think of how you can move the cold from outer rooms in. Instead of having a register at the top of the vaulted ceiling that's ducting hot air into other rooms, have one that's in the floor that blows the cold air from other rooms towards the stove. The heated air will come out of the vaulted ceilings to replace it. It has a couple benefits. First, using registers to move heated air through an attic, you have a tremendous heat difference and higher heat loss in there, the worse thing being any heat lost into your attic, is lost. Ducting cold air doesn't have as high a temperature difference so less heat loss, and any heat lost into your basement is going to rise and help heat the floor above (or help heat your basement) so it's recycled somewhat. Secondly, ducting the heat out means cold air will be moving across your floors towards your stove to replace it making the floors cold and a bit drafty. But, using registers to move the cold air towards your stove means the cold air is going to travel through the register and not so much across your floors and make them feel more comfortable. Of course depends if you have a basement and your layout (how many floors). The first year, do nothing and see how it goes and study what's happening. If it works, don't fix it.

Good luck!

 

[rmcfall]

Thanks for all the feedback, Rhonemas. I think you are absolutely right about closing off the fireplace opening with metal. I had thought about what you suggested, as well as thought about insetting a stainless panel (painted black so it sort of dissappears) just a few inches inside the fireplace opening. It would be real easy to attach some angle iron to the sidewalls and top/bottom of the fireplace opening and then attach a panel to the angle iron on all four sides. Actually, now that I think about, using square stock would allow for a panel on both sides of the metal stock that would create a nice air space to not only seal, but also insulate the fireplace opening.

My last stove was cast-iron and I am now real curious about the soapstone. I've been looking at the Homestead, Heritage, and Mansfield. Unfortunately, the Mansfield doesn't have a rear vent.

Those are some good ideas about bringing cool air INTO the room with the stove. There are definitely lots of factors to consider. But like you said, first thing is to see how it works. In my case, that won't be until next winter. So I've got lots of time to plan the hearth reconstruction, etc. and research what the best stove will be.