Green firewood, or firewood that has just been cut, is a poor performer. It produces little heat, a lot of smoke, and it burns quickly, creating a situation in which much more wood is needed to heat a house. Seasoned wood normally takes a year to dry properly and reduce the water content by 80 per cent. Drying wood in a kiln can reduce that time to just a few months, and even weeks if heat is added.
Acquire an enclosure that provides room for the loosely stacked firewood. The main consideration after the size is that the interior be protected from rain and snow. The enclosure can be an old shed, a tent, a storage unit, or even a car garage.
Lay a floor that allows air to travel freely under it. Wood pallets, hollow concrete blocks, or just two-by-four wood studs laid closely to one another will work. This is where the wood will be stacked.
Create several air intakes. Open windows, side vents, and holes cut into the material are all acceptable, as long as they allow a free flow of incoming air without letting in rain. A bottom vent is the best.
Split the wood so that no piece is over 6 inches in diameter. Stack the wood so that there is plenty of space around individual pieces.
Set up an exhaust fan system that will draw air from the outside, across, and under the wood, and then send it out to the open. This draws the moisture from the wood and vents it to the outside, so the wood does not absorb the moisture back as humidity from the air. The greater the wind flow, the faster the drying.
Provide for a source of heat for the fastest drying. A quartz heater works well because there is no open source of flame that might create a fire hazard with the wood. Place the heater several feet from the wood and all combustibles.
Measure the moisture of the wood every week to see how the kiln is doing. When the moisture level of the wood is 20 to 25 per cent, take the wood out and replace it with new wood.