Domes have been the long term favorite of futurists, and while they suffer from some peoples’ non-acceptance of the unconventional features, they do have several features very desirable to survivalists. The dome of course is a near perfect form of nature. Take an arch, known for its strength in building and bridge construction, and turn it in a circle. Now it’s a dome, and it’s even stronger. Domes use the force of gravity and the extreme compression strength of materials like concrete (cement and sand/gravel mix) to give a clear span, and support tremendous weight on top of it. This can make it a very good choice for underground or earth bermed structures. Depending on your location though, and the fallout or weather you anticipate receiving, covering it may not even be necessary to survive the most extreme conditions. (Note that I am not considering geodesic domes here; note they are more conventional in material and construction)
Sound intriguing? Well, let’s start with the bad news. Here are the down sides, the three problems that stand in the way for most people to buy or build dome homes or survival retreats:
- Lack of reasonable conventional financing (from banks and mortgage companies) since dome homes are not conventional buildings. Not many of us can pay cash for or even build for cash a house or cottage.
- The risk of low resale value. Dome buyers are few and far between, thus finding a buyer to pay at least what you have into can be really difficult. This limits you to almost never moving, or if you do, taking a sizable loss.
- One spouse/significant other simply not willing to be so non-conventional as to not have non-vertical and inward sloping walls, and round or pie shaped rooms.
But now the good news, the advantages of having a dome survival retreat:
- Most have a very high R [insulation] value, and are extremely energy efficient and cheap and easy to live in.
- Most cost about the same as conventional construction, $100 per square foot finished turn key. For the do-it-yourselfer, you can put up the shell for around $30-35 per square foot.
- Most will survive the winds and even the debris from a F5 tornado, or Category 5 hurricane. Pay for a little extra concrete and it will outright stand up to a rifle bullet. Remember also, the aerodynamic shape is helping you too. Wind blows around it, and bullets and debris to some extent are deflected (as with any building, your windows are your weak point, consider shutters). Also note your entire dome (retreat) survives, not just the bunker. It is far more difficult, dark, and energy intensive to live in a bunker after TSHTF in a world where there is no insurance check coming to rebuild.
- Concrete, steel, and ever fiberglass are fire resistant (or fire proof) materials to built with. They are also impervious to insects, critters, and can last practically forever if built right.
- If designed correctly (open concept) they can be equal to or ever cheaper to build than conventional buildings, especially for the do-it-yourselfer.
- In an area of limited access, some of the pre-fab models may be very good choice than attempting to do a conventional stick build.
- Many are modular in design and allow you to plan a really nice multi-family development for a survival group.
- They can be made to be practically air tight, far more so than conventional construction.
These are the four major types of non-geodesic dome homes:
1.) Concrete Domes. The clear leader here IMHO is The Monolithic Dome Institute, http://www.monolithic.com Since around 1970 David South has continuously innovated his unique and near perfect (IMHO) method of constructing the “monolithic dome.” A heavy UV resistant and waterproof membrane is manufactured by Monolithic per design, and then tied down and inflated on site secured to a completed round foundation. You then enter through an “air chamber” (plywood box) as industrial fans keep the dome inflated, and spray polyurethane foam on the inside if the dome several inches thick (depending on dome size). The dome now stands on its own, and using some ladders, scaffolding, you can now use some clever little pieces of metal to hold rebar to the foam on the inside at just the right gap. Using special a concrete pump, nine bag mix (optimal strength) concrete is sprayed on the inside to make dome of a single pour of concrete, thus being monolithic – all one continuous rock. This creates a very pure and very strong dome, but even better, it can have an insulation factor of up R65. So efficient is that, they recommend cooling it with a just a RV air conditioner, and only the smallest wood stove or fireplace or you will simply over cool or overheat yourself. Another great feature is the flexibility. Domes can be stretched wide, tall, or oblong to order, and even better, molded into one another (continuous attached multi domes). A great design is a home with one dome for each room, see http://www.mountainviewdome.com . Making a monolithic dome is something you can hire a certified contractor to do, or you can go to Texas for a week and get certified yourself. Check out the monolithic.com site, it is just loaded with information, articles, and other spin off sites.
2.) Concrete Dome Home with Square Walls: This company is about as close to conventional as you are going to get with a concrete “dome” home. http://www.terra-dome.com The come to your site and use elaborate forms to create buildings made up of either 24’ x 24’ or 28’ x 28’ modules with very heavy concrete roofs. The site has several plans shown. I happen to like #12 for a three bedroom retreat. A lot of concrete in this design, and a very strong building that also gives you a more conventional feel to it inside at least.
3.) Fiberglass Domes. If you are building in a very remote location, an island in particular, where shipping weight is a major cost and concrete may not be available, consider http://www.domesintl.com These modular and lightweight domes can also be made with extra fiberglass to make them strong to the point of being bullet resistant. These models are fast erecting, efficient, and able to withstand extremely high winds. Be sure to see the multi-family designs too, and imagine a survival condo development.
4.) Steel shell underground dome or arch homes. The other option here is the more conventional approach, using a steel structure to make an arch with a half dome on the back, and then bury it. I’ll offer three sites for this, but also an article as a warning on steel corrosion underground, just to be fair since it is a concern. Remember, no matter which method you use to build underground, pay for proper, if not extra, water proofing. The cost of corrective repair, digging it up, is high. See: http://www.formworksbuilding.com or http://earthshelter.com or http://www.americansheltertechnologies.com and (note warning about underground steel corrosion http://www.azom.com/details.asp?ArticleID=1280 )
Sorry if I have missed some types or manufacturers, I tried to present the major ones. For more information on concrete domes in particular, see this association http://www.itsa.info and for some cool further ideas of what you can do, check out this builder http://www.cloudhidden.org/ – Rourke (http://groups.yahoo.com/group/survivalretreat/ )