The Monolithic EcoShell II
EcoShell II – Defined
Like an EcoShell I, an EcoShell II is a concrete, thin shell dome whose construction process includes Airforming. This technique uses an Airform that’s made of a high-strength, high-tech fabric. When inflated, the Airform, looking like a semi-rigid balloon, creates the EcoShell’s dome shape.
The Airform can be removed and reused. With proper care, it can be used 100 or more times. That feature significantly lessens construction costs for projects involving the construction of more than one structure.
For an EcoShell II, concrete is layered onto the interior of the inflated Airform. The shell is not usually insulated, but can be by adding polystyrene beads, vermiculite or perlite into some of the concrete as it is applied. This insulation and the thermal mass of the concrete does provide some thermal protection.
The EcoShell II is a super-strong structure that can withstand hurricanes, tornadoes, earthquakes, fire, termites and rot.
EcoShell II – How it’s used
In the United States and other industrialized nations, an EcoShell II can serve the same purpose as an EcoShell I: It makes an ideal, durable and low maintenance garage, workshop, grain storage, small warehouse or shed.
Nevertheless, some people feel that the EcoShell II is an improvement over EcoShell I, since its construction system allows Shotcrete to be applied to the interior of the Airform. This difference does not seem like much to some; others think it makes EcoShell II’s construction process more technologically sophisticated and therefore more appropriate for a nation with a developed economy.
David South, president of Monolithic, said, “For an EcoShell I, concrete is layered on to the exterior of an Airform; sometimes that is not easy. It all depends on the weather; if it’s good, applying concrete on the exterior of the Airform and allowing it to cure usually progresses well. But it’s a different story in bad weather. Then too, using a concrete gun outside means you must really watch what you are spraying. You don’t want to hit the neighbor’s car, bushes or pets. So we developed the EcoShell II, constructed mostly by working on the inside of the Airform. Now people have a choice.”
EcoShell II — How it’s built
The key to the successful construction of an EcoShell II is Monoform — the right primer. It allows concrete to stick to the interior of the Airform. Because the concrete sticks to the Airform, it is more difficult to get the Airform off after the concrete is set. It is a small penalty for being able to more closely control the spraying of the Shotcrete. It is almost impossible to hand apply the concrete to the interior of the Airform.
See images for step-by-step instructions on how it’s built!
Click here to learn about The Monolithic EcoShell I.
March 13, 2009