Survival homes come in all shapes and sizes. There is no right size or height, it is what ever your going to be comfortable living in. This can be a large cardboard box to a large shipping container to a three story straw bale house.
We're going to explain how to build a few different homes using a few different materials. Depending on where you live, some places will have more of one material than other places, so you'll have to pick and choose what would work for you in your individual situation.
The first one we're going to cover is a cob house. Cob has been used for centuries, some of those houses built hundreds of years ago are still being used today. Cob is made up of clay, sand, straw and water. Generally you would mix 5 gallons of sand, 2.5 gallons of clay, and enough straw (this could be dried grass, it's needed to give the clay and sand some binding), then enough water to mix this so that you can shape it, but still dry enough that you would not use any forms as you would with concrete. There are a number of different ways to mix the cob together, by foot, using horses, oxen, donkeys or by machines like a bobcat or a cement mixer if you have one available. The main difference between a cob house and an Adobe is that the mixture for the Adobe is first formed into bricks which are air dried, then mortared together, they are then plastered over to give them that smooth finished look.
When your building your walls there is no rule of thumb, they can be straight as an arrow, but putting a curve in them will actually give them a bit more strength. You can add shelves, archways, seats, fireplaces or whatever else you would like, as you go along. Only your access to material will limit you, as to how big of a structure you will end up with. If you have access to doors and windows, you can add these as you go. You will have to install the frame work for these items as you build your walls, in order for everything to fit and work properly once your finished.
Cob homes built in the shape of an igloo, as pictured below, don't require any special roof structure. You would just keep bring your walls in a little at a time till you reached the peak of your roof.
A plaster should be applied to the outside of the structure to help protect the cob material. This is quit similar to the cob mixture, but instead of regular straw you would use finely cut up straw or cattail fluff, along with a bit of cow or horse manure if you have access to it, plus a couple gallons of cooked wheat flour.
Before doing any plastering, make sure that you don't have any deep holes in your cob, if there is, fill this holes with the cob mixture first and let dry. If you fill to big of a hole with the plaster, it may crack on you and allowing moisture to seep in under the plaster.
If you have access to some window screen, sift 15 gallons of sand through it. You want the sand as fine and as clean as it can be, also the clay should not have any sticks or gravel in it, the cleaner the smoother the plaster will be. When you apply the plaster to your walls, you want this to be as neat as can be, to give it that finished look. Mix up 7.5 gallons of clay with enough water to the consistency of pancake batter, now mix this with the sand and then add in one gallon of manure. Have on hand a two gallon container filled with warm water, your going to heat the water and then add three cups of wheat flour, stirring constantly until it thickens up. Once thickened, your going to add this to the plaster mix. The final ingredient will be half a gallon of finely chopped straw or cattail fluff.
Now mix everything everything together really well by stomping or what ever method you choose to do. Once this mixture is ready, you will be ready to apply the plaster to the exterior or interior of the house by hand or a trowel if you have one. But first you must wet the cob down with water, only pre-soak the area that your going to cover with this particular batch, then re-wet small areas just before you put the plaster on, no more then what you'll cover in about 10 minutes. The cob needs to be wet for the plaster to adhere properly. This mixture will cover roughly 70 to 80 sq. ft. of area, depending on how thick you apply it. You don't want the plaster any thicker than 1/2" thick and no less than 3/8," unless your going to apply a second coat.
If you have any lime you can add some to the exterior for added protection from the weather, it will make it more water proof. I've also read where some people use boiled linseed oil and melted beeswax in there plaster. By plastering you also keep the insects and rodents from invading your home.
I should make a note here, that cob is not a good insulted material, unless you made it two or three feet thick, but it is good at radiating heat, so keep a good fire going in the winter months.
Pictured below is a cob home with a sod roof.
Earth Bag Home
That pretty well say's it all, this is a home build out of bags filled with earth. The best "earth" mixture is actually about three quarters sand, and one quarter clay, and this is a dry mix, no water involved. The problem with this type of building, if your in survival mode, is the bags. You will need a lot of bags to build any size of home and they have to be strong enough to hold together as you handle them, then tamp them down, by either walking on or hitting with a weight, in order to give the bags more stability as you build the walls up.
If you have a good supply of burlap or polypropylene bags, this is a house that you could build with just a lot of intense labor. As you can see in the picture, a window is made without any type of frame work, a doorway can be made the same way. These can also be built in any shape or size, but like the cob home, it dose not have a lot of insulation value, maybe by mixing a bunch of straw in with the dry sand and clay, this would improve.
Here again the exterior needs to be plastered in order to protect the bags from the elements, insects and rodents.
Pictured below is a earth bag house being built with the doorways and windows framed in. Also notice how flat and level the bags are and how the joints are staggered for added strength. They also suggest running two strands of barbwire about six inches apart in between each row of bags, to keep the bags from shifting to either side. This home will probably have a roof structure such as rafters or trusses when it is completely finished.
We're talking survival log homes here, not the prebuilt manufactured type. The big beautiful log homes that you find in the magazines are built chinkless, meaning that the logs are all fully scribed and saddle notched, then are cut with chain saws to match the log that their sitting on top off. The log is scribed on each side, then the inside of the two scribed lines is cut out, this hollowed out area will hold insulation and allow for settling of the logs. When done properly, there will be no spaces between the logs, they will fit perfectly on top of each other as they settle and shrink.
Pictured below is a chinkless cabin with saddle notches and wooden shakes on the roof.
When you build a survival log home, you will not take the time and
effort to do all of this, unless your planing on staying for awhile.
Ideally, the tools you will need for this quick cabin is a chain saw, 25
ft. measuring tape, pencil, draw knife, hammer & nails, cable
come-along and a stack of 2 X 8 lumber. Short of having all of the above
you will need a fold up saw, (they're generally about two feet long,
with the blade folding inside of the handle), axe, a few pounds of 4
inch nails, string for measuring, some rope for lifting, (paracord would
be excellent) and a couple of carabiners to use as a block and tackle.
Now not all trees grow straight, so the best thing to do is cut short lengths, like 8 ft long, generally at this length they'll be fairly straight and small enough to handle, if you keep to a 8 to 9 inch diameter tree. You also want to find as many dry trees as possible, the bark usually slips off of these and they are a lot lighter to handle then green trees are. Small dry pine would be my favorite to build with. If you don't have any lumber you'll have to split some logs length ways with your axe in order to get a couple of flattened sides to nail your logs too. These uprights do not have to be 8 feet long, just the height of your cabin walls. If your all around 5 1/2 feet tall, just add an extra foot and this will make your wall 6 1/2 feet in height, it will also save you putting up the last two rounds of logs.
By cutting the logs to 8 foot lengths, you can make this cabin as long as you need by adding another 8 foot section to your wall, or you can even make it a eight sided building if you prefer. Next your going to nail the boards uprights (vertical) to the end of the horizontal logs. As your wall starts to grow you'll need to start your next wall and nail it to your first wall to give it added support, then you can keep going up till you reach your desired height. Leave whatever space you want between your walls for a door way, at this time you will also have to plan for your windows by building a box frame where you want your window to go and install that frame work as you build your wall. Make sure to match your window height with your log height so that you wont have to do any extra cutting once the frame is installed. If the window is two feet wide, allowing for the frame work, you will have to cut a few of your logs just under 3 feet long.
Once you have the walls all up, you are now going to quarter round a log (as shown below) and place one quarter upright in each corner, so as it covers over top of your boards. This will give you rounded corners and also adds to the stability of the structure.
The wall should look similar to the illustration below when your finished. Then you would place chinking (moss or rags work good) in between the logs to keep drafts out. Use a stick and jam the chinking in as tight as you can, once the chinking is all done, you can nail small strips of wood over top of the chinking, to help hold it in place, because as the moss dries out it will shrink a bit, allowing air drafts into your home.
You can either build your roof flat or make rafters out of logs.
It's good to have a bit of a pitch to your roof so as rain and snow can
run off. In days of old birch bark was one type of roofing, but it's
also possible to hand split shakes out of pretty well any type of wood. I
seen shakes split out of cedar, spruce, fir, pine and I've also seen
some 100 year old aspen shakes that still looked in very good shape and
probably had another 100 years left in them. To split shakes you'll need
something with a blade as long as you can find, like a machete or a big
bowie type knife, (the pro's use a tool called a froe, chances are you
wont have one) and a wooden mallet, if need be you can use an axe or
hatchet. Shakes can also be used for siding, but you will need to cut a lot shakes.
Cut your wood so that there wont be any knots in your shakes, and as straight a gain as you can possibly find. Usually this would be the first few feet from the butt, so perhaps when your cutting your wall logs, save the butt end for shakes. You might be able to get up to 8 to 10 feet up the butt before you start hitting any amount of knots, depending on the type of wood your using. Here is where the bigger the butt the more shakes it should produce. Now you'll want to cut these in 2 foot increments, as you'll get much better coverage with 24 inch shakes then you will with 18 inch ones. If there are any checks (better known as cracks) in your shake block, make sure that the check runs in parallel with the direction your splitting the shakes, you'll get way better recovery out of your wood this way. Don't worry about how much waste you'll end up with as it will all get used up as kindling and firewood. Also find your largest block of wood or high stump and use this as your work station, placing your shake blocks on top of this, that will save on being bent over all the time and killing your back.
First you need to split your shake block then your first cut will be to take the sap wood off, if you square up your block now, it will go a lot faster, also you want at least a 4 inch face to work with, any less then this and it will take you forever. Take about 3/4 of an inch for your first cut, your trying to make tapered shakes, so ideally you want 3/4 inch at the wide end and no less then 1/8 inch at the narrow end. Now your going to flip your shake block end for end and make your next cut. If you have a nice taper to your shakes, they'll be a lot easier to put on and shed the water better.
Pictured below is a froe, under that is a picture of shingles, but that is how your shakes should be installed, staggered over each joint on the roof or wall of your home.