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How to build an outside wood furnace

With the rising cost of gas and utilities skyrocketing, more people choose to use the alternative methods of heating and cooling their houses. Woods are one of the cheapest materials to buy. These woods are practically useless for anything else because it is so dry. One of the easiest ways to keep the heat billing low is by assembling an outside wood furnace. To have this, here are the basics steps on how to build an outside wood furnace:

1. The first thing you have to do is to decide where you want to place your furnace. Usually, it is placed about 50 to 100 feet away from the house. However, it should be close enough to be hooked into the central heating system. It is required to place your furnace on a level surface. Keeping it away from direct eyesight is a good idea because these furnaces can be ugly to look at.

2. After deciding, your next step is to look for materials. Usually, a lot of steel and metal are involved in making furnace. If you are not familiar with metals, ask someone to come with you when you purchase the metal for your project. You can make several trips to hardware stores for canvassing.

Iron outdoor wood furnace

3. Join the steel together to create a box of at least 35 cubic feet. Let the one end open to attach the water door. Attach the water door using sturdy hinges and a door sealer. It is very important that there is no water getting into the firebox. Make a small round hole on the top of the box for the chimney flu.

4. Put the firebox inside the water jacket. Secure it using a steel base or wire to attach the box inside the water jacket. Be sure that the firebox can be reached from the outside of the water jacket and that there are no leaks in the water jacket. Measure the hole in the firebox to the roof of the water jacket and then cut a hole out of the top of it as well.

5. Weld the steel pipe together to make a chimney the size of the holes you cut into the boxes. You can use a chimney sleeve to secure it to the water jacket and firebox. Place cloverleaf chimney cap inside the chimney. Build flu to go inside the chimney to direct the smoke.

Inside and outside iron furnace

6. Insulated water pipes are advisable to bring the heated water into the house. Attach these pipes to your current heating system and water heating system. You can consult a professional if you are not familiar with heating systems. Put the pipes for about three feet under the ground. Plumbing fittings can be used to attach the pipes inside the water jacket.

7. The last and final step on how to build an outside wood furnace is to fill it with wood. Refill it every after 12-hours with constant use. Put 200-gallons of water to water jacket and build a fire to heat the water. If used properly, the outside wood furnace will cut your heating bills down by about 1/3 to ½ of your current heating bills.

The only disadvantage of these wood furnaces is that when it snows a lot, it might be hard to reach them to refill with wood. However, by following the steps carefully, you will surely apply the learning about how to build an outside wood furnace.

About the author

Nilda Nora

I love writing about interior design.