Tis the season to gather wood, that is.

When cold temperatures settle in to the high country of SW Montana (typically mid to late October) we have to think about heating our house.    Let me digress a bit. In June we were already thinking about stockpiling the wood supply in preparation for the cold months ahead, which are sometimes hard to discern from the “warm months”.  Fact:  There is an 80% chance of the first 28 degree day by September 29 in any given year.  In Spring there is an 80% chance that the last 32 degree day will hit as late as May 27 in any given year.  According to the Farmer’s Almanac, SW Montana has a “year-round risk of frost”.  For those who like hard and fast dates, September 1-10 is the expected first frost most years.  The last frost can be as late as June 21-30.  No surprise that we think about staying warm a lot!

When we decided to homestead in the high country of SW Montana (elevation 5300′) one of our biggest concerns was “how to build a house with a heating system that is energy efficient, affordable, and renewable.  We looked at the standard options; solar energy, wind energy, geothermal energy, and traditional heating utilizing a propane boiler or forced air furnace.  Even with Federal rebate programs and tax benefits solar and wind energy infrasturcture costs still seemed too high (15 year payback).  Traditional heating systems using propane or electricity were easier and more affordable to install (ourselves) but we would have been at the mercy of the market as to the monthly cost of heat. Also, electric or propane type heating systems are questionably renewable. After much research and data collection, we finally looked closely at heating with wood.  We had a little experience heating with wood in our previous home and did not relish the dragging wood in from outside storage areas, removing spent wood ashes, and splitting many chords of wood. Then we came upon the idea of an outdoor wood-fired boiler system.

The outdoor wood-fired boiler idea was an intrequing concept.  The self contained boiler was designed to be situated completely  outside along with the wood (no more ash, soot, and wood debree in the house).  More intriguing is the fact that SW Montana has millions of acres of public forest land, a lot of which has been insect killed in the past decades.  Did I mention that you can get a permit to collect dead timber on National Forest Service land for $5.00 per chord?  After several weeks of research pertaining to the pros, cons and installation requirements of an outdoor wood fired boiler, we decided that a hydronic heat system powered by an outdoor wood-fired boiler was the right decision for us.   No more messy wood  or ashes in the house.  Plus, the system would also heat all of our hot water when the boiler was operating during cold months.

What a great decision!  Hydronic floor heat is quiet and the warm floors are wonderful!  The installation required a little over 5,300 linear feet of PEX piping, attached directly under the floors, which took us about a week to complete.  After that, installing the zone valves, heat exchanger on the water heater, and plumbing to the outdoor boiler only took a couple days.  At the same time we decided it would be beneficial to increase the R value of our walls and attic area to R-39 and R-60 respectively.  The boiler we selected (Central Boiler out of Minnesota) can easily burn 3 feet long logs approximately 9-10 inches in diameter.  Due to the design and efficiency of the boiler, we are able to load the boiler with wood once in the morning and again in the evening and it heats our entire house, basement and garage (a total of approximately 6000 sq. ft of heated area) with about 8 chords of wood per year.  If you do the math, the cost to heat our homestead and domestic hot water, runs us about $250 per year (yes, per year) which included the cost of the wood collection permit, fuel and all other expenses incurred for collecting our own wood.  The payback on this system is about 5 years.

Before it was all said and done, we decided to install a wood stove in the great room just for the ambiance of a crackling fire. After a year of use we found out that we could conserve wood by heating the entire house with just the indoor wood stove in the shoulder seasons (when the daytime temperatures are still above freezing and the nights dip slightly below). I should also point out that we installed a small high efficiency propane “backup boiler” that automatically kicks in if the water temperature in the outside wood-fired boiler falls below 120 degrees. The backup boiler allows us the flexibility to not use the outside wood-fired boiler without worrying about freezing pipes. And, when we decide we are too old and feeble to collect wood someday, we can simply use the propane boiler.