Saturday, January 26, 2008

My Survival Cabin - Heating a Cabin

No Heat

During the summer of 2003 heating didn’t seem that important. Quickly I realized that July highs of 100 degrees can easily plummet to the mid 40’s in the dead of the night. At the time I was staying in the Small Cabin at Bear Ridge. The 8’x 10’ Cub House, as it is now called, has no insulation or windows for that matter. It sits on top of the ridge and the powerful valley winds turned the comfortable daytime structure into an icebox when the sun went down.

Propane Heat

The first heater purchased was a small propane heater. This unit screwed onto the top of a 1 pound propane bottle and was completely useless. Not only did it fail to heat it also would freeze up after about an hour of use. Needless to say, I did not spend much time at Bear Ridge that first winter. Since then I have purchased a larger unit that can keep the cabin and the dogs fairly comfortable during the day if I have to be gone. This 28000 BTU propane unit is easily started, very efficient and warms quickly.

The downside is that you have to have propane for the unit, and it goes through 20 pound tanks like candy. Since I am not real comfortable with propane availability in the near future I am resisting installing a larger 250 pound tank. Plus I don't really like the idea of needing an outside company to fill the bigger tanks.

Kerosene Heat


Spring of 2004 brought the completion of stage one of the Big Cabin at Bear Ridge. This 120 square foot first addition was screened in on the front side. During the summer two fleece blankets where hung over the openings at night and a 23,000 BTU portable kerosene convection heater, was used for warmth. It was warm, comfortable and the open screen windows kept the mild kerosene smell under control. I highly recommend this heater, it has saved me on many cold nights.

Kerosene costs about $3+ a gallon and during a cold 24 hour period you will easily burn up to five gallons. In addition only certain suppliers will carry this product so if you run out it can be difficult to restock unless you have a 100 gallon or better tank. The larger tanks are nice but you run into the same problems seen with propane resupply. Remember to stock up on wicks.

I also purchased a small 10000 BTU reflective kerosene heater. This unit just smokes and really doesn’t add enough heat to justify the burning eyes and throat. Don't get one.

Wood Heat

April 2005 the second addition was completed bringing the total square footage to 280. The screened openings were replaced with a large double paned window and set of French doors. A 100000 BTU wood burning stove was installed. If you build a cabin you must have a wood stove. They are relaxing and produce a very nice quality of heat. Additionally you can cook and heat water on them. In June the square footage was increased again to 408 with the completion of the third addition.

Wood is readily available and if you have a cabin it should be your primary heat source. The only downside is that you have to be there to feed the fire. Pellet and cob stoves can remedy this but those feed stocks must be purchased from a supplier who may not be available in a power down situation.

Remember wet or green wood does not burn well or produce good heat. So even if you plan on cutting your own wood when you get to your cabin you will need a good supply of dry stuff to burn with it. If you have a lumber mill close buy the long bark strips they cut from the trees are usually cheap and easy to handle. Just pull in from the end of your truck and cut to length.

Insulation

The cabin was not insulated until November 2005. Insulation is the single most important, not to mention one of the cheapest, things you can install to help with heating. The temperature was hovering around zero and with a roaring fire and the kerosene heater running at full it was only 45 degrees inside. After placing a layer of R19 insulation in just the ceiling the temperature climbed to a toasty 80 degrees.

The latest expansion was completed in January 2007. It added roughly 200 square feet floor space and approximately 120 square feet of double paned insulated glass on the north side overlooking the mountains. The cabin is now one fat “T” shaped room a little over 600 square feet in size. Fitted 5’x 6’ fleece blankets are placed in the four large windows on the north side at night. The walls were also insulated. The blankets really help.

Don't forget the floor. Unless you are slab building, a lot of cold air will come into your house from the floor. Since my place is built on a hill side the back of the cabin is at ground level but the front is elevated by about 4 foot. Cold winter air blows up underneath and you are quickly frozen out. Put at least thick carpet on the floor but I would recommend 1/2 inch 4 x 8 foot Styrofoam panels with a layer of tongue and grove plywood over them, cover that with carpet. This really makes a big difference.

Passive Solar Heat

The winter of 2006-2007 brought an unusually large about of snow. There were times in January where the roads were impassable and many residents, including me, were snowed in. The cabin stayed warm during this period but an enormous amount of wood and kerosene were required. Even though there were several feet of snow and the air was very cold the temperature outside on the south facing wall of the cabin was comfortable.

The south side only had one small window. In February 2007 four large floor to ceiling windows were installed on the south wall. They are actually old glass doors and did not cost anything. The south side of the cabin now had roughly 112 square feet of glass. For each square foot of south facing glass you can generate approximately 200 BTU of heat. So during the day the gain is about 22400 BTU of heating for free. During the night these windows are covered with a thick fleece blanket.

One day in late February 2007 it was 3 degree Fahrenheit outside. A digital thermometer was placed on the floor at about 10 a.m. Within a few minutes in the sun it was reading 82 degrees. This is actually warmer than heating with kerosene and you are not burning $5 worth of fuel every day.

Making use of passive solar heating is critical if you don't want to spend a fortune on kerosene and wood. Not only are you getting the solar warming but the sunlight flooding into the space is a great mood enhancing benefit and dogs love it. Over the 2007 summer a large sun room was installed on the south facing side of the cabin and part of the existing south wall will be used to install a “Trombe” solar heating system.

Diesel Heat

I plan on purchasing a small 45000 BTU diesel convection heater this summer. Diesel is just as expensive as kerosene but you can get it at any gas station. This is good because you are not dependent on someone delivering the fuel. Eventually I will be able to make my own biodiesel if thing go as planned. I will let you know how that goes.

Best Heat

I think the best way to heat a house would be passive solar warming with glass southern exposure heating a thermal mass slab that the cabin sits on. Back this up with a nice wood stove.

4 comments:

theotherryan said...

This series is outstanding. For your heating situation I would keep the kero heater (bigger one) lying around. Kerosene essentially never goes bad. Also it edges out propane because an individual can go to a hardware store with 4 or 5 20 gallon cans in the back of their truck and leave with lots of fuel then consolidate it into a larger tanks. You can not do that easily with propane. The diesel heater will push the kerosene to a distant second fossil fuel heating system. Wood stoves are great for quality of heat, efficiancy and safety. The biggest advantage kerosene (or diesel later) has over wood is that it will get the house warm FAST. If you come back cold or after getting dunked in a lake cranking up that heater is going to det you out of the danger zone much faster. It is also useful for when you get in late at night and want to get the place up to a comfortable temperature fast.

Have you considered insulated shutters? I'm envisioning a piece of sheetmetal with foam insulation on the inside that you can close at night of before leaving for awhile. They would also help add a level of security for when you leave. Keep up the great work!

Ryan

BigBear said...

Ryan,

I am looking at insulated shutters. But remember the cabin was situated for the view, so the front windows are not exactly easily shuttered.

Originally I had planned on a large insulated barn door like structure that would could be placed over the front windows but the design didn't work out. But hey, I will retro fit something that is warm and workable.

fallout11 said...

Excellent, real world experience piece!

Use the space under the house for firewood storage, if you are not already. Not only will this cut down on convective heat loss during the winter, it is a good convenient place to keep your firewood stash dry and nearby (important after heavy snowfall).

Anonymous said...

Great and very useful information. I could ramble on but I think my brief sentence says it all.

I look forward to your future postings.