A concrete dome home can offer occupants increased protection from fire, high wind, tornado, and earthquake disasters.
Fire Protection
January 12, wild fire in Oklahoma burned thousands of acres and consumed the neighbors home in a house fire, Jerri Strube, owner of a newly constructed Monolithic Dome home told Erica Harpold, reporter from KAUZ-TV Channel 6 in Wichita Falls, Texas, “Instead of having a Safe Room, that a lot of people do – you know – build in their houses now-a-days – we have a safe house.” The marks on the outside of her concrete dome, where the raging fire burned right up to her home and stopped, bear witness to the structure’s ability to withstand heat and flames.
Concrete is fire resistant. It will not burn at the temperatures present in a house fire, according to the Portland Cement Association.
Tornado and High Wind Protection
Another disaster faced by homeowners is wind and tornado damage. High winds cause loss of roofing that must be replaced as well as damage to the exterior of homes. Tornadoes often shatter wood frame homes and scatter the debris. A dome home with its concrete construction and aerodynamic shape is less susceptible to damage from wind or tornado. When wind driven debris strike a dome shape, the curvature of the structure does not pose as much of an obstruction as a flat walled structure and therefore is less likely to be damaged.
The dome shape does not provide an overhang for a tornado to "Get its teeth into" and remove the roof, according to FEMA, the Federal Emergency Management Agency in its news release in May 21, 2011 from Clinton, Missouri.
Earthquake Protection
An earthquake shakes apart the most vulnerable points in a structure, the ninety-degree connections where floor and walls and ceiling and walls meet. A concrete dome lacks these connection point by the nature of the dome shape and construction. During an earthquake the dome responds as a unit without connection points. The reinforced structure is better able to maintain its integrity than a traditionally constructed wood frame house.
Protection from projectiles
If a traditional wood frame home is struck by a projectile like a bullet, it would provide minimal protection for the occupants. Unless the projectile struck a door, a stud or part of the framing, it would likely penetrate the wall and cause damage inside the home. A concrete dome provides protection for its occupants on all its surfaces except for windows.
Bullets fired from weapons ranging from a .38 caliber pistol to a high powered M-16 A2 penetrated at maximum 2.8 inches into the concrete. Since the common thickness of a thin shell concrete dome home is 3 inches, a bullet would likely not penetrate a concrete dome. These findings are according to U. S. Military testing of foam coated Shock Absorbing CONcrete known as SACON. The report, Proceedings of the Tri-Service Environmental Technology Workshop, "Enhancing Readiness Through Environmental Quality Technology" held in Hershey, Pennsylvania, May 20-22, 1996.
The military report concludes that "SACON designed using Type 1 portland cement and can be expected to have the chemical characteristics associated with conventional concrete made with this same cement." The finished shell of a concrete dome home affords occupants protection similar to the SACON tested, in almost any location within the home.
Strong Shape Provides More Protection
The dome, shaped like one end of an egg, is one of the strongest shapes in nature. At Brigham Young University, students in the College of Engineering supported a plank with a hard boiled egg at one end and a cement block at the other. The students placed 45 pounds of weight on the plank and the egg held the weight without breaking. The dome shape's strength is attributed to its even distribution of weight, all the points of the structure share the stress evenly.
Cement is a readily-available relatively low-cost building material worldwide. Modern building methods for constructing thin shell concrete domes can make these structures available to most people who are building a home. In contrast to the traditional method of building a house, a thin shell concrete dome could allow the average person to live in a home that will likely continue to be viable for centuries, can provide better protection for the occupants from fires, tornadoes and earthquakes, and provide a less toxic, quieter, and more secure environment.
Jon Thompson - Jon Thompson - freelance article and commercial writer with background in education, business, advertising, sales and emergency ...
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