How big a wood stove should I get?

September 17, 2008 2:09 PM

How big a wood stove should I get?

I am thinking about using a wood stove as a secondary heater in my 750 sq. ft, two-storey house in New England. It already has a propane furnace with a single heat exchanger under a large grate in the floor (on the first floor) which I would like to use just to keep the pipes from freezing and use the wood stove for comfort. Insulation? Not totally uninsulated... Should I oversize the square foot rating given the uncertain insulation and second storey?

posted by geos to home & garden (6 answers total)

does it make sense to consider a pellet stove instead? They have automatic hopper-style feeders, so you don't freeze to death in the middle of the night.
posted by jenkinsEar at 2:15 PM on September 17, 2008

Most wood stoves are underrated in terms of square footage heated. Don't oversize or you will roast. If you fill your stove up before you go to bed and damp it down, you should not have to fill it in the middle of the night.
posted by Xurando at 2:24 PM on September 17, 2008

Yeah, don't overrate — wood stoves like to burn at capacity, and won't be as happy always having a small and smoldering pile of wood inside. Do you have a good wood stove store you can talk to about the size of your house and it's actual insulation?

You may need to add more insulation around the pipes, if the furnace is what is keeping the under-floor stuff from freezing. Or maybe your furnace can be set to recirculate the air, without heating it?
posted by Forktine at 2:59 PM on September 17, 2008

According to this article, if you want the stove to keep a fire overnight, you might want a firebox that's 2 cubic feet or larger.

I used a small woodstove (a Waterford Leprechaun) as a secondary heater in a pathetically insulated 720-square-foot trailer. The specs for that stove don't mention firebox size, but the stove is similar to another brand's small stove that has a 1.3 cubic foot firebox. It supposedly produces 33k BTU max.

The stove heated about half of the trailer. The tiny firebox caused two problems: I had to feed it extremely often (every 1.5-2 hours) and the fire never survived the night. In fact, the stove was only slightly warm to the touch the next morning.

If you plan to buy firewood, using a tiny stove like mine means you have to be careful to pre-order wood that's no more than 16" long. If you cut your own wood, short log lengths mean more cuts and more splitting--more work.

I now have a tight, well-insulated 1100-square-foot house with an open floorplan. Last year, I tried to heat it with the Waterford. The stove did fine in mild temperatures. But when the temperature outside got into the teens or lower, I couldn't get the indoor temperature out of the 50s. I also got tired of constantly feeding the stove.

I'm now upgrading to a stove that's about 50% bigger, probably a Jotul F 400 Castine.
posted by PatoPata at 3:37 PM on September 17, 2008

I have a small stove (Waterford 100B) in a small 2 story house. When it's fired, it heats the space well, but it will not maintain coals overnight. The forums at Hearth.com are quite helpful.

My stove is rated to heat 1,000 sq. ft., which is about what I have on 1st & 2nd floors. It's supplemental heat, and I'm quite happy with it, but you may want something large enough to maintain coals overnight. The cost of stove installation is non-trivial; don't skimp on safety. That said, I love being able to sit by the fire; it makes winter nearly pleasant.
posted by theora55 at 4:07 PM on September 17, 2008

Lots of good advice here. I am only chiming in to caution about using the same chimney for both propane and wood. You may want to look into safety and/or regulations.
posted by terrapin at 4:27 PM on September 17, 2008