[samclem]

Very few fireplaces in modern homes are really designed to give off heat. They are almost always neutral or "heat losers" when operating. They typicaly give off very little heat to the room, and they send a lot of the already warm air from the room up the chimney when they are operting. The exceptions to this rule would be any fireplace that has an "insert" which circulates air around the firebox (with a fan) and blows it into the room.

I would not recommend any of the non-vented propane (or natural gas) heaters. They are often called "ventless" or ""blue-flame" heaters. No matter how clean they burn, you are deliberately introducing some carbon monoxide into your home. In addition, they dump a LOT of water vapor into your house, which is not good for indoor air quality and can cause mold/rot inside your walls and in your attic when that water vapor condenses on cooler surfaces there. These heaters are illegal in many places, including all of Canada. They are cheap, but not a good answer to your problem (IMO). Even where they are legal, the restriction is that they should only be operated a few hours per day. Is it only cold where you are a few hours per day?

A significantly more expensive but very effective answer to your problem is the "direct vent" heater. These can be vented straight through an exteror wall, and they take air in through a concentric tube in the same opening. Very straightforward instrallation if you have an exterior wall in the room you want to heat. Unfortunately, these cost about $1000.

Here's a good link with a discussion of these heaters. http://www.alsheating.com/

You could buy an insert for the fireplace you have, and turn it into an effective heater. If you go this route, one thing to be very careful about is proper venting. A masonry fireplace often is not a suitable vent for propane/natural gas appliances, since the relatively lower heat content and higher water content/acidity of the effluent leads to condensation in the flue and relatively rapid disintegration of the mortar. Some folks will be happy to install inappropriate appliances for you, and they won't be around when your chimney starts crumbling. A flue-pipe all the way to the top, like Ed's, is the way to go.

How about a combined heat pump unit? I know you said "no electricity" but it doesn't get too cold where you are, and these things do a good job of heating down to approx 40 deg F. You could use the same device to heat and cool your house. They use only electricity, and are much more efficient than resistance heat. If you have central A/C you could use the same ductwork. If you want to do this on the cheap, you could just buy a window unit--it looks like a big window AC unit, but it heats, too. If you want to go really cheap, you can usuallly find these as used equipment (they are typically used to heat/cool hotel rooms, and these businesses frequently change them all out at once, even if they are working fine).

Good luck!