P
AGE
18
O
PERATING
Y
OUR
A
PPLIANCE
(C
ONTINUED
)
A W
ORD ABOUT
W
OOD
(C
ONTINUED
)
Constructing a Wood Shed
The drawing to the right details the
construction of an inexpensive wood shed
that will promote drying, increasing the
heat output from your wood.
3' Depth
8' Width
Sheet Metal Roofing
2x4 Purlins
4x4x2 Posts Spaced 8' Apart
2x6x12 Rafter
Siding and Girts
(Optional)
2x8x8' Girder
What Type of Wood is Best
Choosing the kind of firewood to burn in your appliance depends on what is available to you.
Softwoods, such as pine or fir ignite and burn quicker, but require more frequent loadings and are less
suited for overnight burns. For longer burns, with less frequent loadings, we recommend harder woods
such as oak or maple. The chart below details the BTU (heat) output of the various species. Note the
higher BTU output of the harder woods. The best arrangement is to have softwoods for starting and
immediate heating and hardwoods for overnight and sustained burns.
SPECIES
(20% moisture)
LBS./CORD
(Approximate)
BTU's/CORD
(Approximate)
Hours per Cord at 40,000 BTU's per Hour
(Approximate)
ALDER
2540
19,050,000
476
APPLE
4400
33,000,000
825
ASH
3440
25,800,000
645
BIRCH
3040
22,800,000
705
CEDAR
2060
15,450,000
386
COTTONWOOD
2160
16,200,000
405
DOGWOOD
4320
31,725,000
793
ELM
2260
16,950,000
423
FIR, DOUGLAS
2970
22,275,000
556
HEMLOCK
2700
20,250,000
506
MAPLE
3200
24,000,000
600
OAK, RED
3680
27,600,000
690
OAK, WHITE
4200
31,500,000
787
PINE
2250
16,875,000
421
REDWOOD
2400
18,000,000
450
SPRUCE
2240
16,800,000
420
How to Buy Wood
Wood is sold by the cord (4' wide by 4' high by 8' long). Buy wood in the spring and summer, when
prices are lower and it will have plenty of time to dry. If buying in winter, have the wood moisture
tested (test several pieces). You will receive up to 25% more heat from a cord of dry wood than from
wet or green wood. Rotate your wood so as to allow for the maximum drying time for all pieces.
Don't Burn Wood Scraps, Garbage, Paper, Wax Logs, Coal, Etc.
Wood scraps from construction are typically chemically treated, making them difficult to burn and
dangerous due to emitting chemicals. The same holds true for garbage, solvents, driftwood containing
salt, cardboard, and colored paper. Coal and wax impregnated logs burn especially hot, creating a
possible safety hazard. In addition, all the aforementioned items may create excessive creosote.
