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Firewood vs. fireplace logs

Dear Jim: I always buy firewood to use in my open fireplace. I burn it just for ambience, not really for heat. I thought about using fireplace logs instead. Are they as efficient and as good for the environment?

-- Jon F.

Dear Jon: If you are using a standard open-front fireplace, it is not efficient, no matter what type of fuel you burn. It may feel warm directly in front of the fireplace, but it draws a huge amount of heated air up the chimney. This makes your furnace or heat pump run more overall. At the very least, install tight-fitting glass doors on the fireplace.

Burning regular firewood (called cord wood) can be good and bad for the environment. From the standpoint of climate change, it is good. When the wood burns, the same amount of carbon dioxide is released as if it were allowed to rot on the ground over time. When other trees go up where a tree was cut for firewood, they will consume the carbon dioxide released by burning the wood.

On the negative side, burning cord wood gives off a lot of particulate matter (ash and smoke). If just a few homes burn wood, this is not a problem. If most homes burn wood for heat, there may be an air pollution problem. Air pollution is not just a summertime issue.

Burning manufactured fireplace logs can be a good alternative to burning cord wood if you don't use your fireplace as the primary source of heat. They will produce plenty of heat, but the cost per Btu of heat is higher than burning cord wood. You can often find cord wood for free at construction sites.

There are quite a few manufactured fireplace log options. The most common is a combination wax/sawdust log. These are usually rated by the estimated number of hours of burn time. These burn significantly cleaner (up to 70 percent less smoke and ash) than cord wood and are much easier to handle.

In the past, most fireplace logs used petroleum-based waxes with the sawdust. Today, more environmentally friendly logs use natural-based waxes. This reduces their carbon footprint and our overall oil demands. These newer logs burn just as well and as hot as the petroleum-based ones.

Even more environmentally friendly are Java-Logs. These manufactured logs replace the sawdust with recycled coffee grounds. With all the coffee shops around today, you can imagine how much grounds there are. These burn hotter than sawdust logs and produce more brilliant color. If you tear the wrapper, they smell like coffee.

If you are a purist and want to burn all wood, several companies now make 100 percent sawdust blocks and logs. This is similar technology to making wood pellets for pellet stoves. A pallet holding 34 cubic feet of these produces as much heat as a full cord (128 cubic feet) of firewood.

The following companies offer artificial fire logs: Barefoot Pellet Company, (570) 297-1297,; Duraflame, (209) 461-6600,; North Idaho Energy Logs, (208) 267-5311,; and Pine Mountain, (877) 402-5185,


Dear Jim: I want to use a portable heat pump in my bedroom and sometimes in the dining room. I know it will have to be vented out a window, but we have casement windows. How can it be connected to a casement window?

-- Ann T.

Dear Ann: Most portable heat pumps and air conditioners include a flat window adapter. This adapter is connected by one or two ducts to the heat pump.

Build your own tall adapter which fits in the partially open casement window. It must be wide enough so the flat adapter can be mounted vertically in it. Your adapter needs triangular top and bottom sections to close the opening. Crank the window sash tightly against weather stripping on your adapter edges.