Revisiting the Wood Stove

The old is new again
Dutchwest2478web
I grew up in a house that was heated by a wood stove. After many years of racketing around in strange places where wood was not a common fuel, we are building a modern home in which a wood stove will once again be the major source of heat.

This Dutchwest noncatalytic wood stove may look like one of the old cast iron stoves, but a lot of technology has gone into making it far more efficient (approximately 70%).

An outside air connection is standard, meaning that all air necessary to support combustion is taken from outside of the home. No room air is used to support the fire. No vacuum is created in the room when the fire is burning briskly, because the combustion chamber is sealed. Air comes in from outside, feeds the flame and exhausts through the chimney without mixing with room air.

Regular wood stoves and fireplaces use room air for combustion and suck outside air in through every crack, which makes them virtually useless in subzero weather because they bring in cold air faster than they can heat the room.

This stove is primarily a convection heater, although it does provide a radiant heat. Room air is forced through heated passages in the stove by a blower and then it is dispersed through the room as a gentle flow of warm convection air. The stove can also be used for occasional cooking and is designed with a flat top for this purpose.

We opted to heat our new house with a wood stove, because we have enough wood already cut on the property to supply us for several years. We may install a heat pump next year after we have a chance to see how we manage using wood stove, ceiling fans and electric heaters in the more distant rooms. Power interruptions are common in this area, especially in the winter, so we need to make sure we can keep the house warm and cook food even when the power is out.

There is one little problem

The one problem I am running up against is a lack of current data on the construction of protective coverings for the floor and back wall surrounding the wood stove. We picked out a beautiful ceramic tile to protect the floor and wall from the heat of the wood stove, but the stove people seem to think that the weight of the 420 pound stove will crack the tiles, even though they will be mounted on 1/2" Wonderboard.

The tile people say, "No problem!" but they haven’t done a stove installation in a very long time. On the other hand, the stove dealer’s installers regaled me with a story about a recent installation where they put the stove down gently and the tiles began to creak as they walked away.

I am asking for information from those of you who are currently using wood stoves. What kinds of attractive stone, tile or brick have you found that combines heat resistance with ruggedness? This stove has heat shields on the back and bottom so heat is not the main concern. I look at the cast iron legs with their sharp edges and want to make sure that there is no way that the stoves weight will damage the hearth material under the stove.

I am open to any useful suggestion. Someone even suggested that I put a 24" x 36" slab of slate under the stove and use 12" tiles to cover the rest of the hearth and backstop.

Any suggestions from you experienced wood-burners?

This entry was posted in Moving to Floyd, Possibly Helpful Advice, post-corporate. Bookmark the permalink.

0 Responses to Revisiting the Wood Stove

  1. Hello David,

    I have recently replaced my wood stove in my home in Chestertown, on Maryland’s Eastern Shore. We replace a an older wood stove with a Hearthstone Heritage Soapstone woodstove. I did a good deal of research before having the stove installed. I don’t think that you can simply install the stove over tile and Wonderboard. You will not have sufficent protection under the stove.

    Your stove manufacturer should be able to tell you what R-value is required in the areas around and under your stove to protect you from radiant heat that could cause excessive temperatures and could potentially ignite combustible materials.

    For instance, our stove requires a minimum R-value of 1.2. The Wonderboard only has an R-value of .100 and you ceramic tile 0.020. In my judgemet clearly not enough to get you to a reasonable R-value.

    I would offer two suggestions. Since you are involved in new construction, simply have a concrete footer poured in the crawlspace area that will support yout stove. Make it obviously the depth of your crawls space and as wide as you need to provide protective areas on each side of the stove. You can then place your backerboard over the entire floor and have your tile installed. This way you support your heavy stove and are fully protected, since concrete has an R-value of .950 per inch. If you don’t want to put in the footing, you can use either Micor or Fibrefrax, both are ceramic boards with an R-value of 1.100. The tile can be installed over these surfaces.

    I hope this information helps. Sorry for such a long post. But you need to be aware of these issues. By the way I very much enjoy your Blog and read it daily.

  2. Ray says:

    I have a cast iron clawfoot tub in my bathroom which I would guess weighs in the 250-300lb range (empty) and it sits on tiles that are those little 3/4″ octogonal ones that typically come in white and black. Anyway, even when the tub is full of water (and me at 220 lbs or so) there hasn’t been any sort of impact on the tiles.

  3. Have you considered a corn or pellet stove?

    I recently installed mine and find it very economical and efficient (85%) and it is rated to be installed into mobile homes so heat and weight are not a real issue.

    One unexpected effect is the rather nice odor of popped corn you can barely notice outside the house.

  4. KPBHD says:

    In regards to the blower. I have instaled the 2 speed blower on my extra large Dutchwest. My problem is, on hi if im standing about a foot away, I cant feel the air. Now it could be I’m expecting to much out of it, but I’m baseing this on a old coal stove I have in my barn that has a blower, I can stand 15 feet away from it and still fell the air. Any help would be great. Thanks. Kevin

  5. We have the variable speed blower on the medium size Dutchwest. This blower puts out air in a broad fan from the top of the stove and you can feel it about two feet away.

    When our stove is burning well, it will heat up the house (1650 sq ft) to 80 degrees. Most of the time we have to put the damper on to keep the stove from throwing so much heat out.

    My only complaint is that the blower is noisy when it is set at the highest speed. We normally operate the blower at about 1/3 speed.

    Perhaps you can get a technician from the dealer to come out and look at your stove if it isn’t running right.

  6. Loren says:

    Hello,
    I came accross this site as I was searching for ideas to reduce clearence space for my wood burning stove. I have the Vermont Castings “Defiant” & was wondering what protective covering you decided to use on the floor & wall.

  7. I used 3/8 inch thick ceramic tile backed up by 1/2 inch backer board which is a concrete and fiberglass composite on top of 13/16 plywood over an air space.

    There is a 3/4 inch airspace behind the back part of the hearth and 6 inches of air underneath the bottom portion of the hearth.

    My building inspector advised me to raise the hearth for added insulation and for greater ease of use. I actually didn’t need the extra insulation because the bottom of the stove barely gets warm, but the added height makes it easier to load the stove.

    Do a search for “wood stove” using the search tool on the left sidebar and you will see all of the articles which mention this wood stove and many of them show images which will give you a better idea of the construction.

  8. Tom Kara says:

    I have an old King heater, which may not weight as much as the Dutchwest wood stove, but certainly isnt’ light either. I added additional joists under the house so that it was 12″ OC underneath. Then 3/4″ plywood subfloor. On top of that, two layers (instead of one layer) of cement backerboard, with large ceramic tiles on top. There is no evidence of cracking. Tile cracking is a function of floor flex. If you adequately reinforce a framed floor, it should hardly flex if at all unless the weight is truly extreme. I always overbuild when loads may be large. The notion about insulation requirments under these stoves should be backed up by real data about how hot they get underneath. This old King wood stove gets only moderately warm underneath, even with a blazing fire, and the ceramic tile has never been warm to the touch, even with only three inches of air between the bottom of the stove and the tile. I think some building codes are based on unfounded assumptions. I used cement board with tile behind the stove, floor to ceiling, 14″ clearance, and it gets only slightly warm. We use a SafetyThimble to go through the wall to a stainless line masonry chimney. There’s an article at http://www.woodheat.org about “The outdoor air myth” for wood stoves which points out that much of the outdoor air supply regulations were based on intuitive assumptions rather than scientific study.

  9. I read the article at http://www.woodheat.org about “The outdoor air myth.” It is a wonderful case of “junk science” used to promote an agenda.

    I’m not sure why so much emphasis was spent dismissing the effect of outside air sources on keeping a house warm.

    Having grown up in a fireplace heated home, I am acutely familiar with the phenomenon of a roaring fire warming our front sides while cold wind whistled under the door and through the windows during cold Massachusetts winters and chilled our backsides.

    I recently installed a Dutchwest woodstove and insisted on an outside air supply. We had many days of 19 degree weather this past winter and the stove warmed a 1650 sq ft house with no cold air drafts from doors or windows.

    Occasionally, I would run a test with the outside air feed diverted to the inside. The cold draft from the doors and windows was immediately perceptable.

    I read the so-called “scientific reports” with some amusement because the primary reason for claiming that dangerous gases would spill from the stove or fireplace was that an exhaust fan would create a huge vacuum that would suck smoke and CO out of a sealed stove combustion system. DUH! How long do you run an exhaust fan? Only when cooking, normally.

    If you run a giant exhaust fan, it will drag smoke out of a fireplace quicker than out of a sealed stove.

    If the weather is freezing cold, and the fire is blazing away, the answer is quite simple: DON’T RUN THE FAN!

    The same is true of the example where wind creates a pressure envelope which causes air to go down the chimney instead of up. A fireplace will disgorge choking smoke and gases into the room. A sealed combustion system with outside air might possible backflow, but the discharge is vented to the outside. Again, I say somebody must have had a financial reason for dismissing outside air feeds as a myth. I would ask what organization benefitted from publishing that report. It is really junk science.

    As far as the heat put out underneath a stove, I agree that my stove barely heated the floor underneath the combustion chamber even when the fire was blazing hot. We found that the heat was so moderate that the floor was only warm to the touch. Results would vary depending on the stove, of course, so it is better to over design than to skimp on insulation and air space.

  10. gordo says:

    “It is a wonderful case of “junk science” used to promote an agenda.”

    And what agenda would that be?
    There are legitimate pros and cons to using outside air kits, and there are also serious safety concerns. This has been discussed recently at hearth.net:

    http://www.hearth.com/econtent/index.php/forums/viewthread/2496/P30/

    David says:

    Read the rest of the hearth.net forum comments and you will see no documentation of safety concerns.

    Anecdotal evidence unsupported by facts is what makes urban legends persist.

    I call it “junk science” when someone tries to prove that something is dangerous by bending physical laws.

    As for an agenda, the only group which might benefit from the “dangers” of outside air supplies would be developers who want to cut costs. Outside air supplies do take additional labor. If I wanted to identify the agenda, I would go back to the very first article published about the “dangers” of outside air supplies and see who provided the “facts” or wrote the article.

  11. gordo says:

    FYI: I have the same exact stove (Dutchwest). For floor protection you must meet the R value mentioned in the install manual (1.19). The biggest R-Value bang for your buck is actually an air gap! So if you can prop your non-combustible layer up on some metal studs, it almost doesn’t matter what non-combustible material you use. But if you are looking for the “easiest” homemade hearth pad – just use one sheet of micore 300 with a sheet of cement backer board on top of that (Durock for example) and put your ceramic tiles on top of that. The tiles will not crack from the stove, just be gentle when placing the stove on top of it.

    Here’s another tip – its EASY to move that nearly 500 lbs cast iron stove around BY YOURSELF if you just take advantage of some simple machines. I bought 4 $10 dollies from harbor freight (you could also make them yourself with some 3″ castors and some boards). I jacked the stove up with a regular floor jack normally used on my car, slipped the dollies under (I suppose you could use just two dollies, but I figured one for each leg would distribute the weight better). Once on the dollies, it is easy to move around, even on carpet, there is only 30 lbs on each wheel (4 dollies=16 wheels, and 480lbs/16=30).

    Once the stove is positioned in front of the hearth pad, it is equally easy to get it up onto the pad. Remove the bottom heat shield from the stove first, then stick greased boards (2x4s, 4x4s, perhaps a single 2×10 or 2×12 would be best) under the stove. Only grease the top of the board starting where it will initially touch the stove). The back end of the 2x4s should be up on a stool that can handle some weight. Then jack up the front of the 2x4s using the same car jack as before. Jack it up only as high as necessary to slide the stove down and into place without any danger of sliding too far!

    And your done. Stove moved and positioned into place by one person using almost no muscle power…

  12. Mark says:

    Gordo:
    What did you use to attach the micore sheet to the floor and the cement board to the micore?

  13. Jim Gourd says:

    This blog is just what I was looking for on a new instalation of a wood stove. I’m wanting to put the chimney flue of a freestanding wood stove inside of a “false” fireplace surround. It will look like I’m setting a freestander inside an old fireplace opening. I’m doing this to hide the bend in the chimney flue. I cannot avoid a ridge beam directly above and on center with the stove.
    Since this is a new install, I have the freedom to plan ahead. This installation is on the second floor of the house. Weight is of great concern. I plan to use cultured stone to cover the fireplace surround. The surround being made of wood framing covered inside and out with microfiber board. Near the ceiling I plan to install vents in the surround to allow the heat from the flue to re-enter the room close to the ceiling. At this point a ceiling fan will distribute the heat around the house. (small house)
    My question is: Providing I follow code, does this sound plausible?

    David says:
    This sounds like a great idea providing the flue is one of the double wall flues that are used for going through enclosed areas. There is definitely a need to observe clearances or you could create a fire hazard.

    Get a knowledgeable building inspector to buy off on your plans before you start investing effort and money on that solution.

    Good luck!

  14. Ella Lanier says:

    Hi, I just found your blog about woodburning stoves. I have one that we took out of our fireplace because I was told that it was unsafe. It has the words “Hearth King” on the front. But I cannot find a website with any information. Do you happen to know anything about such a stove?

  15. Vince says:

    Hi,

    Just doing some reading about the all great install ideas.
    I have a Regency F2400 but have not yet installed it. Heck I have all summer to do this and want to be sure I do everything properly. Appearances are a major concern too and my decorator abilities are limited.
    One note about outside air is that in Washington State, or at least my county, outside air is required or the install will not pass inspection.
    The stove is going in a corner where a prefab zero clearance once was. The old fireplace and non structural wall are now gone. I will make it a 90 degree angle corner once again. I’m laying a base of concrete with steel tubes running throughout for additional cooling. Then will top with tile. I’m not so concerned about the walls because I am following the manufacturer’s required clearances plus some.
    So–after that long winded prelim–my question is–can I use the existing outside air kit already in place from the zero clearance?
    Thanks in advance.

  16. Hi Vince,

    I am no expert, but the outside air kit on my house stove is a 3″ diameter aluminum flex tube like a dryer vent, only smaller.

    I suggest that you make the outside air tube as large as you can so that it won’t interfere with the draft.

    When we start our stove, we often have to open the lower ash door for a minute or two until the fire really catches. This takes room air and allows it to shoot up through the grate and the fire just takes off. The manufacturer strictly warns against this for a good reason. If you are careless, the fire will get hot enough to crack the front glass and turn the walls of the stove red.

    On the other hand, you can see from what I am saying that this is a reliable, if not totally safe way to get your fire started quickly.

    Our first winter, we had to buy freshly cut wood which was not dry by any means. The only way we were able to keep the fire going was to discover that opening the grate would let us burn wood that was still wet.

    May you have dry wood and a good draft in your chimney, then you won’t have to improvise.

    Another interesting fact we learned. The clearance figures are safe, but not all that conservative. Our stove is 13″ from the back wall and the wall never got more than slightly warm for many months. Then our power went off and we used the stove without the blower…Surprise!!

    The back wall got quite hot and was painful to touch and the floor under the stove got really warm also.

    It turns out that using a blower on the stove reduces the stove temperature probably thirty degrees because the heat is being transferred to the air which is being blown into the room. Stove blowers are a bit noisy, but they can be turned down low and they keep the rooms cosy without having a stove that is super hot. The whole house is comfortable, not just in front of the stove as is the case when the stove has no blower.

    Best regards,

    David

  17. Bill says:

    I have a question about a Dutchwest noncat wood stove I just bought. The connection collar on the stove has stop tabs that limit insertion to one inch, but most stovepipe has one and a half to almost two inch tapered end before the stop point. Also the stove collar is not evenly tapered, and the taper is excessive on the stove side so that it is not possible to insert stovepipe without first cutting it down. Dutchwest told me to see the dealer, and the dealer told me to use a hacksaw to make the pipe fit. Other brands in the dealership had good smooth collars that presented no problem with inserting stovepipe. I wish I noticed that before buying. Could this be a safety concern? Comments please?

  18. Emily West says:

    Does anyone know of a way to prevent a Vermont Casting non catalytic woodstove from “puffing up” and smoking

  19. Mark Neady says:

    Can I add something about wood stoves?

    Wood fuel is wood used as fuel. The burning of wood is currently the largest use of energy derived from a solid fuel biomass.

    Wood fuel can be used for cooking and heating, and occasionally for fueling steam engines and steam turbines that generate electricity. Wood fuel may be available as firewood (eg. logs, bolts, blocks), charcoal, chips, sheets, pellets and sawdust.

    The particular form used depends upon factors such as source, quantity, quality and application. Sawmill waste and construction industry by-products also include various forms of lumber tailings.

    Wood may be burned in a furnace, stove, fireplace, or in a campfire, or used for a bonfire. Wood is the most easily available form of fuel, requiring no tools in the case of picking up dead wood, or little tools, although as in any industry, specialized tools, such as skidders and hydraulic wood splitters, have evolved to mechanize production.

    The discovery of how to make fire for the purpose of burning wood is regarded as one of humanity’s most important advances.

  20. Parker Stafford says:

    About insulation under the stove: I grew up in Floyd and heated exclusively with wood in a 100 year old farm house. All we used under the main stove was a commercially available heat reflector which was sheetmetal and some fibrous insulation less than half an inch thick. Under that was linoleum, under that was the flooring which consisted of wood planks. We never had any charring or burning of our floor. This stove got quite hot and was rather large since it had to heat about 4 rooms.

    I have seen brick pavers used in some installs and in the right place, looked quite nice. You are surrounded by artisans out where you are in Floyd, so I am going to challenge you to contact a potter and have them roll or extrude you some special ceramic tiles/bricks for your stove. You can have a very low profile frame made to hold these tiles in place, someone with some welding experience, or a blacksmith. Have them make you a set of pokers, etc. while you are at it. You should have access to a blacksmith or two for that where you are as well.

    Now when I say custom ceramic tiles, I am talking something that will be about three times as thick as what you might find commercially. The advantage is you can have a pattern stamped into them and have them fired bisque or you could have them glazed. Luckily you would not need a ton of these so it will be light on your pocket. People will marvel as they hang around your stove during the winter months at the incredible tile job you had a local talent create for you. Not all clays are created equal, and you want something that will be strong but not overly brittle. You also don’t want something that hasn’t been fired high enough. An experienced potter should be able to help you in picking a clay body that would be appropriate. If they are to be grouted, patterns could be put into their backsides by the potter for a little extra “tooth.”

    Good luck!

    Parker S.

    Disclaimer: the poster is not a potter, nor knows nor has contact info for potters in the Floyd area. The poster just knows enough to get you and he into a good bit of trouble, but its trouble well spent.

  21. Here is an article that may help. It covers the standard clearances for wood burning stoves and what you can do if you don’t have enough room for the clearance:

    http://www.woodstoveaccessoriesblog.com/category/wood-stove-installation

  22. alec says:

    as to how hot it gets under a stove, just ask my old cat. we would have a fire cranking along in our Jotul cast iron stove and the sides and top would be blazing hot but he would just hunker down underneath it, his head almost brushing the top, and he would sit there comfortably for hours. must not get too hot, eh?

Leave a Reply

Your email address will not be published. Required fields are marked *

fifty three − 49 =