Hi, some good questions :)

LPG is a fossil fuel, so is ultimately not a sustainable or renewable fuel, but on the plus side, is a lot cleaner burning than oil or petroleum products such as kerosene.

I have a slow combustion wood burning stove in our backpacker hostel, it is the only form of heating for a very large room, and is very efficient. I have not found that it produces a lot of smoke inside the room. If smoke is going into the home, then the chimney is positioned wrongly, or is not drawing enough.

spud

Ah, finally something I can ring in on.

Several things here.

If you are experiencing smoke in your living area, there are a few things to look at why you are having what may be backdraft. The height of your chimney or stove pipe is one. Is it clean? Even a little built residue can cause an uneven airflow. Cleaning the pipes and chimney is vastly important for several reasons. If you are using a gas insert, chances are slim you have much buildup, but it is possible. Or, is something simply blocking the exhaust aspect of this? Like, a bird's nest or rodent activity. I know it is a pain, but having this checked would be my #1 thing. (reminds me that I have to clean our flue out, something I do at the beginning of a burn season, and about 2/3rds of the way through).

Where is the flow of air come in to feed the up draft. Is there any kind of piping that feeds the gas insert from the outside? Or is it taking it's air from the available air in the room/house? If it is taking air from the room only, it may be as simple as cracking a window for a few minutes to allow the an airflow to being.

The height of your chimney or stove pipe flue matters. If you are still having issues with backdraft when you fire up the gas insert after tending to the above things, then you look at extending the length of the chimney pipe, if it is indeed pipe. Bricks are of course more involved. But even extending piping by 18" can make a difference in terms of air pressure at the base of the gas insert and then the air pressure at the top of the pipe. That can matter too.

Then of course, the gas insert itself. Has it been cleaned? Is it burning efficiently? Are there any heat capturing mechanism like pipes or vents that reclaim heat that heads up the chimney pipe? The kind of gas insert can be poor, mediocre, or engineered to capture disperse heat. Another way of saying is the gas insert for decoration, or is it of a type that captures the BTUs before they exit the chimney.

Finally, and what is most important of all... air flow within the house. This *really* matters. One can have a superbly efficient wood or gas stove, but if there is poor air circulation, especially if this is a primary heat source and needs to push the heat to other parts of the house, then you really need an airflow strategy. Ceiling fans for starters, can help. In our home, a simple combination of a stand alone fan and opening certain doors creates air flow to all parts of the house. We cool using similar methods too. But if it comes down to it... even a stand up fan that pushes heat sideways to other parts of the house to distribute heat, even if you are spending a few $$ for electricity, the savings in heat can be significant.

For instance, I have a small but powerful blower (Stanley) meant for shops. I position it behind the stove and force air through the venting system. It is on a timer. Depending on the temp, it comes on every 15 minutes for a couple of mins, to once an hour, adjusting it of course. It pushes out a tremendous amount of heat and gets air circulating. Necessary for our house and when it gets below 0, it helps. But circulating heated air from a gas insert, even if it is just ambient air that comes from the radiant heat from the insert can make a big diff. Ceiling fans might be all that are needed.

All depends on where you live, the construction of your house, is it heat efficient or inefficient, and so on. To get maximum heat for the cost of gas tho from any stove, gas or wood, or pellet, air flow from the heat source make a huge diff.

If you are looking into a pellet stove, all the above still applies. Height of chimney, incoming air flow, and so on. If you are using a pellet or wood stove however, one trick is to light a few wadded up pieces of newspaper to heat the chimney enough to start some airflow.

You should never have to experience smoke into your home however.

I should have asked to begin with... are you looking at getting a fuel efficient way of heating your home? If you don't mind, perhaps you could share little things like... is there an existing fireplace already? Wood stove? Is there stove piping for a chimney already in place? Are you looking for gas because of the convenience? Because you would have to feed the beast if you used a pellet stove. Weather? What kind of weather do you have in the winter? Arctic circle? Moderate?

Anyways... finally, something I can ring in on and I am always happy to talk about heating one's home with wood or pellets. Am not prone to gas, but most of the principles are the same. If you can throw back a few answers to the above, would be happy to chatter a bit more.

ck