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How accurate are square foot heat ratings for wood stoves?

Discussion in 'Modern EPA Stoves and Fireplaces' started by Mambwe, Jun 24, 2021.

  1. Mambwe

    Mambwe

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    I'm in the market for a new wood stove and I'm looking at the Lopi Evergreen. Their website says it heats up to 2,000 square feet. My house is probably 1,500 square feet total. The room where the stove is will be approximately 1,000 square feet with 12 foot ceilings. Will this stove be overkill?

    I currently have a forced air heat system, but would like to use the stove as much as possible for heat. I'm worried that this stove will be too strong and we will hate wood heat. I don't want to be cooked out of our house. I live right outside NYC.
     
  2. stuckinthemuck

    stuckinthemuck

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    Many of us deal with stoves that are “too big” for our houses at least during a portion of the year. Those who start burning at the first frost and stop when the overnight temps bottom out in the 40’s are technically firing a stove that is oversized for their heat demand. We learn to build smaller fires or burn wood that is lower in BTU’s. I’d be more concerned with undersizing a stove than oversizing. I don’t think that stove would be overkill but I don’t know what year your house was built, what your window situation is or how well insulated it is. Worst case scenario, as you’re learning how it behaves, you have to crack open a door or window to improve your heat loss. I’d rather have a stove that can produce “too much” heat than one that doesn’t produce enough and forces me to use my oil fired boiler for heat. JMHO. Good luck.
     
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  3. wildwest

    wildwest Moderator

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    IMHO they are not accurate, determined in an ideal atmosphere which many homeowners do not have. I've seen here some have WELL insulated houses that need extra ventilation, to my home before we remodeled most of it, we had two large stoves running 24/7 (1600 sq ft) but still had to supplement with electric space heaters- it runs the gammut between the two extremes. That said like above, you can build a small fire in a big stove but one cannot build a big fire in a small stove. I would though, caution against a type of stove being sold without air controls.
     
    Last edited: Jun 24, 2021
  4. brenndatomu

    brenndatomu

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    Manufacturers pull those number out of their posteriors!
    How many cubic feet is the stove? That means more than their "sq ft" ratings...you'll want to oversize a bit anyways since you have high ceilings...that eats up some heat. How cold your local climate can get in the winter and the insulation/air sealing levels of your home factor in a great deal too.
    As was mentioned, I'd prefer to see someone oversize a stove a bit before undersizing, unless they plan on just being very part time burners. A "full time" burner will want some firepower...easier to build a small fire in a large stove than it is a large fire in a small stove...you'll learn to manage the fire with how much you load and what type of wood you use depending on how much heat you want...so there is a learning curve to it all, we all go through it, even when just switching to a new model stove, that can change things up too!
    Another thing is a small stove won't "hold the fire" as long as a larger one...if you want to be able to have a good 8 hour overnight fire, 2.3-2.5 CF is about the minimum I'd want (unless this is a cat stove?)
     
    Last edited: Jun 24, 2021
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  5. Canadian border VT

    Canadian border VT

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    Most companies from my experience get those numbers by how many square feet it will heat in Atlanta Georgia..
     
  6. PA Mountain Man

    PA Mountain Man

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    When it's really cold:shiver:, blowin hard:dennis: and the electric goes out,:doh:
    there is comfort :campfire:and joy :drunk:
    in a large capacity wood stove and a huge pile of dry wood:stack::stack:.
     
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  7. Backwoods Savage

    Backwoods Savage Moderator

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    First of all, the ratings should be for cubic feet rather than square feet. In your case, multiply 1,000 by 12 and then do the same for 1,000 by 8 and you get a good view of why I make that statement. Simply put, it takes more btu to heat that extra 4,000 space.

    Switching from forced air heat to a wood stove can be fantastic. How great of a change depends much on the house, the outdoor temperature and how the stove is operated (and that last also greatly depends upon the fuel you are trying to burn).

    Will that stove be overkill? I highly doubt it will be too much stove and you will probably be very happy with it. You for sure will want a ceiling fan in the stove room with the fan drawing up in winter and down in summer; also we run our ceiling fan on low speed. Higher speeds create too much draft and low speeds move plenty of air.

    As stated above, the wood stove is called on to be able to hear in variable conditions. For example, in the fall (or spring) when the temperature drops into the low 40's and lower it is time to get the stove working so your house is comfortable. Later when it gets cold, sometimes below zero, that same stove is called on to work much harder. So the owner can't just set a thermostat and forget the heating unit. He must regulate the heat and he does that by the type of fuel he burns, the amount of fuel he puts in the stove and how he regulates the stove.

    The good part is that it is not all that complicated if you understand. It is somewhat like writing a computer program or planning a trip or any task. Determine what you want done (output); determine what is needed to produce that output, etc.

    Here is some more information which could help you: (1) Primer on Woodburning by Backwoods Savage | Firewood Hoarders Club
     
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  8. moresnow

    moresnow

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    Lots of stove options out there worth looking at. Lopi is a well respected manufacturer. I have no Evergreen experience but have been around the Liberty model. Good solid stove.

    Research as many makes and models as you can. Look into the difference between Catalytic equipped stoves and secondary burn tube/baffle equipped stoves. You will also find models that are using both systems together.

    Burn time is a really important consideration if you are planning on letting the stove carry much of your heating needs. Duration between reloads has to fit your schedule/availability. It's zero fun running back and forth to a stove that needs tending often to keep up.

    There is a nice variety of brands being used by the members here. Fire away with questions on most any brand/model you research. Chances are good somebody here can provide hands on experience.

    Manufacturer's square foot ratings is just a very general guide for selecting a stove.
     
  9. billb3

    billb3

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    Screen Shot 2021-06-25 at 4.15.37 PM.png
    That's supposed to be the specs for a Lopi Evergreen

    For Long Island (sam3e as at my house) I think they calculate 40-50 BTU per square foot (probably 8 foot ceilings) which would be the middle range of that stove for dead of Winter. A 2.2 cu ft stove sounds like a good fit for 1500 square feet . Might have it going close to full tilt boogie on those rare nights it gets down to 0ºF . Might have to have a supply of pine or poplar to have short fires when it isn't that cold out. That's what I do with a 2.0 cu ft stove, one quick short fire first thing in the morning, hope it doesn't get too hot and then another quick, short fire just before supper.
     
  10. brenndatomu

    brenndatomu

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    2.2 CF would be the absolute smallest that I be willing to have with 1500 SF...especially with those high ceilings...
     
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  11. bushpilot

    bushpilot

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    It sounds a little small to me, if anything.
     
  12. billb3

    billb3

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    On Long Island ? It's not Key West but it's still tempered a bit by the Atlantic.
     
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  13. Mambwe

    Mambwe

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    The wood stove is part of a big renovation. We will have new windows and we are planning to use spray foam insulation. This should keep the house pretty well sealed, so I am thinking that would help us if the evergreen is a little undersized. I’m going to add the fan to the stove, so that also will help.

    We want to go with a modern looking stove that has a pedestal. I’ve been looking at the Lopi Evergreen and the Osburn 2000. I like that the Lopi is Made in USA and everyone says the quality is up there.

    Does anyone know of any other stoves that are modern looking with a pedestal base and also good quality?
     
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  14. bushpilot

    bushpilot

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    Have you looked at the Englander line? Englander

    The NC-32 is an updated version of the popular NC-30, shich has been discontinued. It was a very popular stove for the budget minded, but a good performer in a basic stove.
     
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  15. Mambwe

    Mambwe

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    Do you mind if I ask how much home you are heating with a 2.0 cu ft stove? Which stove? Looks like we are in a similar climate.
     
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  16. billb3

    billb3

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    1750 sq ft ranch. The two rooms on the far end can get a little chilly when it is 0ºF outside, plus the doors are usually closed as that end of the house can get closed off with pocket doors. One of the rooms is on its own zone so can be heated if needed. It's an extra bedroom. We've never run the stove full blast as it tends to get run for longer burn times. The heat usually comes on early in the morning. We're not trying to heat exclusively with wood heat . More of a keep the house a little warmer than you might if you had to listen to the oil boiler running all day and all night. Wood replaces about 2/3 of the usual amount of oil, plus the house is warmer, especially the kitchen and family room. Not too shabby considering the original plan was to have emergency back-up heat and a cooking surface in the Winter should the power go out for an extended period of time. I have a 2200 watt portable generator as well as we have our own well for water. True North TN20 wood stove. It's a little small for dead of Winter but 90% of the time it's just right. Stove is NOT in the middle of the house which would be ideal. The EPA BTU rating is 14,000-30,000 and that sounds about right. House is fairly well insulated and all new windows and doors.
     
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  17. Eric Wanderweg

    Eric Wanderweg

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    I have a Lopi Evergreen and live in a Cape that's about 2,000 square feet. That's including my finished basement though, which the stove does not heat since it's on the first floor. So in reality I'm heating about the same space as you will be (although to Backwoods' valid point, cubic feet is a better metric to go by) My ceilings are 8 foot. I find that it heats my space more than adequately. On warmer days all I do is have smaller fires, or one in the morning and one to carry us through the night. If I load the firebox chock full when it's 45 degrees out, I'll be opening windows in short order. It takes some trial and error to really learn how to get your stove running optimally in the space you have, but all in all there's no voodoo involved. I think you'll be fine with the Lopi. I know it usually doesn't get brutally cold on the island, but I think you'd be better off having a little more than you need than to come up short. You can always throttle back your burns, but there's nothing you can do if your stove is simply not large enough.
     
  18. Hoytman

    Hoytman

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    I wouldn’t pay much attention the btu ratings, or trust them, on their website. The reason...the btu ratings shown for the Endeavor/Liberty are shown as being lower btu than the Evergreen. No way that Evergreen will out perform that Liberty. No way!!

    I feel the Lopi Endeavor would be a better choice for your situation for three reasons:

    1. The ability to load East/west of north/south.

    2. Cooking. Cooking can be done on the Evergreen as well, but the the Endeavor/Liberty you have the option for higher or lower temperatures for cooking. May not seem important until the electric goes out and then you’ll likely be glad you opted for the step top.

    3. The Endeavor in the old catalog was rated slightly more than the Evergreen. Absolutely no reason for it to be reversed now. Endeavor has a slightly bigger fire box and thus more btu’s...even if slightly more. The Liberty firebox is even bigger.


    For your sq footage, plus the high ceilings with the new insulation to come, the Evergreen or the Endeavor should be sized just right...mid-sized which is what you want. Neither of those models, in my opinion are too small, nor too big. If you are worried about too big, then go with your original choice, the Evergreen. If the advantages of two cooking zones and two ways of loading wood are not a concern, then the Evergreen should work great.

    When these guys talk of getting a bigger stove, well, how much bigger? I can tell you that too big is useless because you can’t use the stove as much as you’d like and it might as well be a boat anchor. I have three wood stoves that are all too big and I have to say I’d rather have one too small and supplement a week or two with my fuel oil. You have to do some of your own research compared with the home data you have and you have to decide what is too big of a stove. Choose wisely.

    Ideal is a mid-sized stove, one that is neither too small nor too big...one that can and will be used the entire season.


    I would not discount the SBI/Osburn/Drolet stove at all. Their customer service is likely the best in the business from many forum users, and they build a well made quality stove. Made in Canada, but so what. They no how to build a heavily built stove...just like Lopi, Buck, Regency and others.

    I think you’re on the right track with a mid-sized stove for you space and situation. Just remember the Lopi Endeavor of considered a mid-sized stove as well.

    Firebox size rather than btu output is likely a better decision maker because most btu ratings are not reality anyway.
     
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