Our cave-dwelling ancestors probably developed the basics of the method when they ran out of available caves but still thought of south-facing hillsides as attractive places to live. Today, underground building is far from burrowing deep beneath the lawn. Most underground homes are either concrete (usually), pressure-treated wood (sometimes) or naturally rot-resistant wood (seldom) structures, built in an area excavated from a hillside (usually) or flat land (sometimes). The one-story structure is usually roofed over with a flat, heavily reinforced, waterproofed deck and oriented with windows and doors facing south or in an arch facing southeast, south and southwest. All walls and roof decks are insulated from the exterior with thick, waterproof foam sheets. The excavated material is carefully pushed and tamped back into place up against the walls. On the roof, the material is replaced gingerly and often without tamping, creating an R-value of 50 or more, depending on the soil type and depth. It would be difficult to build a quieter home. Utilities are installed pretty much like an ordinary balloon-framed or concrete structure. The costs of underground construction generally run about 10 to 20 percent higher than standard balloon-framed homes, particularly when using a contractor who has never built underground before. In areas where soil is thin, imported fill can also drive the costs up. Environmentally, underground homes tend to blend in with their surroundings after a few years, although trees must be kept from growing in the way of the southerly exposure and roots from some species of trees overhead can pose problems decades down the road. Once overgrown with native vegetation, the entire structure blends in nicely with its surroundings.
One of the first "survival"-type books we bought is this great book by Mike Oehler entitled "The $50 and Up Underground House Book". It has great info about the very most basics of digging out a shelter that is very liveable. You won't have a lot of space, but if built correctly, could have a LOT of privacy as it could be very well hidden.Question: Will an underground or earthbermed home be defensible? Yes, if you have cameras installed or if you've designed it well. Also, when drawing up a floor plan for your underground or earth-bermed home, remember in the northern hemisphere, the open part must be south-facing to take advantage of the natural heat in the winter and the cooling in the summer. Will your property support that? If your entrance is on the north, design your driveway to come around to the back or "side" entrance.
Perhaps you'd consider having your underground house with a "fake-out" on top? Just a teeny little cabin with 4-directions for your viewing pleasure (read: defense).
More info about underground housing:
When considering an underground house floor plan, look for the following applications:
- The house floor plan should blur the distinction between indoors and outdoors. The purpose is to exist in close harmony with nature.
- The windows should be honeycomb style to harness solar energy.
- Since the windows for this type of floor plan don't open, an intake vent system with filters should be installed to draw fresh air from outside. The filters help keep out unwanted pests.
- Air should be fanned from a solar collector through the home duct work into a rock store beneath the main living space. The store system maintains an efficient heat-exchange which works with the insulating soil to maintain a comfortable temperature year round. A good system would require no additional heating or cooling.
The dome shaped rooms give rise to maximum floor space and minimum wall area. Floor areas do not to conform to traditional housing expectations and and the living spaces are defined with curved walls with no sharp corners. Natural sunlight can be channeled into the house via the use of a skylight lined with natural reflective materialsHere's the last part of our series of alternative housing construction methods:
These methods of home construction only begin to hint at all the alternatives out there. If more exotic methods and materials are considered, homes can be built using everything from lightweight, aerated concrete blocks to recycled tires and cordwood. Aluminum cans, reinforced fiberglass, recycled steel and even sawdust have been used as basic building materials. The only ingredient common to all is the devotee who, for one reason or another, sees each method full of obvious advantages and few disadvantages.
But before you decide to create the American dream using methods and materials from someone else's vision of how life should be, consider all potential drawbacks. For instance, most real estate agents agree that selling offbeat homes is a significant challenge. Homebuyers generally shy away from methods and materials they don't understand. So resale of your alternative home may not be as quick, easy or lucrative as you, or your heirs, would like it to be. Additionally, home insurers may look askance at methods and materials with which they've had no experience. Although foam block, timber frames and log homes have gained acceptance, straw-bale and underground homes may be harder to insure at reasonable rates. Likewise, local building codes and inspectors may delay onsite approvals and permit issuance simply because the methods and materials are so new and require extra time to understand. And finding contractors willing to try your methods, which may appear woefully untried to them, is always difficult and usually expensive. So before you try an alternative home-construction method or material, it's best to talk with several people who have used the method and lived in the resulting structure for more than five or six years. It's only after 10 years or more that any home's shortcomings - be it alternative or standard construction - become obvious. Although home construction and ownership always involve compromises of one sort or another, it is best to understand in advance what concessions you will have to make.
Note: This is a blog for people who are looking to provide a long-term place to live and for disaster preparedness. Take all of the information you can gather, from here and elsewhere, and be sure to weigh all pros and cons for your housing decision. Do you intend to live forever in this house you plan to build? Then you probably don't need to worry about resale value. Live in mostly desert terrain? Then the organics method may work for you. Want to live underground? There are many types - earth bermed, hidden entrances and so many other ways to choose from. This is a big decision so be sure to make it wisely. It may be a matter of life or death.
Don't worry - we're not hanging ya out to dry. When we get more info or people want to share their experience of using alternative methods to build their dream survival home, we'll post them. Stay tuned! :)