The first geodesic dome greenhouse in Hillsborogh County was erected on Sat, Jan. 15th, when we put up this GeoAtrium on the lawn of the New Berean Baptist Church in Brandon. It took a team of 10 about an hour to raise the pre-engineered dome and panel inserts. New Berean will use the GeoAtrium to protect the crops they grow for a produce stand for the poor. The greenhouse will protect the crops from weather extremes, rodents and insects.
Today, John Martin and Paul Kranz visited New Berean Baptist Church (newBerean.org) to participate in a garden workshop hosted by Five and Two Food (fiveAndTwoFood.com). Hannah Frisby of Five And Two Food gave information on how her organization assists local churches to start a garden on their church property. The goal is to provide produce for the needy.
DomesToTheRescue saw this as an opportunity to employ the use of geodesic domes as greenhouses. Paul Kranz gave a briefing on the domes that Bell Shoals Baptist Church sent to Haiti this past spring. He went into how geodesic domes make excellent greenhouses.
The night before the event, John, Paul, and Jack, erected a life-size model of what the superstructure looks like for the greenhouse and placed it over one of the boxes in the New Berean garden. A wonderful time was had by all.
Bell Shoals volunteers are processing orders for what DomesToTheRescue is calling “GeoAtriums.” The greenhouses cost $500 each in parts, but the labor will be donated. The church-customers will be asked to send a conveyance to Bell Shoals to pick up their kit and Bell Shoals will send one supervisor to the customer so help their crew put together the kit.
The kit is the same size as the GeoHomes that were sent to Haiti, but instead of covering the dome with retired bill board tarp, DomesToTheRescue will wrap triangulated frames in 4mm polyurethane for 14 of the 15 triangles on the dome. A special 15th frame will be constructed for the door. DomesToTheRescue is accepting orders at this time.
It has been observed that the triangle is the strongest polygon because it is the only polygon with a locked hinge; it has two sides that are immobilized by a third side. I would like to tell you that the base pentagon of our tent is stable, but it would only be stable if the entire sphere were constructed like Dustin Feider’s O2 Treehouses (http://www.o2Sustainability.com/). The best way to put the fabric on the dome is to lay out the fabric flat on the ground, and roll the dome over on its side on top of the fabric like a pig-in-a-blanket. But, the base pentagon collapses when you turn over the dome on its side which not only bends the STARPLATES, but makes it nearly impossible to roll and, thereby, cover. So, we stabilize the pentagon by triangulating it with two 13-foot braces which we construct from four boards temporarily borrowed from another kit.
Above is what the dome looks like top-up with the brace in place. Notice how only two braces are needed to stabilize the base pentagon with three triangles.
The two 13-foot braces are made by nailing two kit boards together so that they overlap three feet. You only need to use two 3-inch nails included in the kit on each board going through into the other. We want to use the kit boards because the bracket hardware requires that the boards connected to them have a hole bored through the long side 1.5 inches on center from the end.
There are three brackets included in the kit. Two of them are C-brackets which are made by taking a Simpson Strong-Tie (R) No. MSTA12Z and drilling a 3/8-inch hole in the center. The ties are bent around the end of a 2-by-4 so that the center hole you drilled is at the center of the end of the board.
Mount each C-bracket to the two base STARPLATES of one of the triangles on the pentagon using a 5/16-by-1-inch hex bolt, washer and nut included in the kit.
The other bracket is the V-bracket which is made by taking a Simpson Strong-Tie (R) No. RTF2Z and drilling a 3/8-inch hole in the center. The arms of the bracket are bent to a 36-degree orientation. It doesn’t have to be perfect, physics will take over!
Mount the V-bracket to the base STARPLATE that is opposite the two STARPLATES on the pentagon that the C-brackets are mounted to. Use a bolt, washer and nut as you did with the C-brackets.
Use the same technique above to secure the other ends of the two braces to the V-bracket. The braces are now in place and the dome can be flipped all around without any structural impairment. The braces should remain on until the augers are installed to make sure the five points of the base pentagon are on the same circle. After that, you can remove the braces from the brackets and the brackets from the STARPLATES. To prevent a major cannibalization of kits for the braces you can just select four boards and have a crew take the brackets and hardware and follow behind the crew that erects the domes. This would be one way to limit the need for multiple braces, brackets and hardware especially if the fabric installers also install the augers. In fact it would only take one set!
Many people ask me who designed this. I guess God did! The icosahedron was first written about by Plato (circa 400 B.C.) and has been named one of the Platonic solids, accordingly. Whether Plato discovered it is still a mystery. The icosahedron has since emerged in a grand way in the study of viruses. Virology shows that the icosahedron is a popular shape for viruses to take because “a regular icosahedron is the optimum way of forming a closed shell from identical sub-units” (http://en.wikipedia.org/wiki/Virus). It fits the definition of a Platonic solid: (1) the 20 faces are the same shape (equilateral triangles) and size, (2) the 30 edges where two triangles come together are the same length and angle, and (3) the 12 points where five of the faces come together are the same in that they all appear on a common sphere. So, I did not design the icosahedron. All I did was adapt the shape to this application. As such the following dimensions are given. With an 8-foot edge the icosahedron (and thereby this tent) is 11.5 feet high, has a footprint perimeter of (5 * 8 =) 4o feet with an area of 110 sq. ft., and a diameter of 12 feet. It contains almost 1000 cu. ft. of space.
The kit includes
– 25 struts, 8-foot 2-by-4s with 3/8-inch holes drilled through the 4″ inch side on 1-1/2″ centers from each end. 20 of the struts are regular kiln-dried boards. Five of the boards are pressure-treated and will be used to construct the base pentagon.
– One 11-count box of STARPLATES (http://www.strombergschickens.com/starplate_building_system/starplate_index.php).
– 50 sets of 4-by- 5/16-inch carriage bolts along with 1 washer and 1 nut to hold the boards to the STARPLATES
– 1 retired 14′ X 48′ billboard tarp with tasteful advertising, with 3 feet folded back so the tarp only covers 45 linear feet, with one grommet on both ends in the bottom hem so a nail can be used as a door latch
– One 14′ X 14′ tarp for the floor
– Nails with waterproof washers to secure the tarp to the dome
-3 Simpson Strong-Ties(R) with bolt sets to hold the braces in place to triangulate the base pentagon, one RTF2Z (http://strongtie.com/products/connectors/RTC-FWH.asp) and two MSTA12Zs (http://strongtie.com/products/connectors/HRS-ST-PS-HST-LSTA.asp).
– 4 three-inch nails to nail four boards together for two makeshift 13-foot braces for another kit
-1 stainless steel bowl which inverted over the top hole to be used as a cupola with hardware to attach it to the top STARPLATE
– 1 hammer and two 5/16-inch wrenches
-3 augers to secure the dome to the ground at three points
Here is a way to build geodesic dome tent kits to help solve the shelter shortage world-wide. This process was inspired by the Haitian earthquake (20100112) and the resultant amount of refugees, and by Pastor John Martin at my church, Bell Shoals Baptist Church (www.BellShoals.com), Brandon, Florida 33511, who has embarked upon an historic journey to address the shelter crisis in Haiti by a pilot project of sending 100 tents to Haiti before 20100430. We will be sending over the tents as kits to the Southern Baptist Convention compound near the Port-au-Prince International Airport. The kits will be placed in a container at our makeshift factory at the church. Then, we will ship the container to Haiti by way of the Port of Tampa (www.TampaPort.com). Once we get the call that the kits are secure within the compound, we will send a team of trainers down to the compound and train the compound staff on how to teach the locals how to put together the tents. We will return to Tampa and construct and ship as many kits as donations will permit. It you follow this blog, you will learn from our successes and failures how you and your organization can build these kits, too. If you need help, please call John (813-689-4229×225) or me, Paul at 813-777-5422. Happy dome building!
The trick to wrapping up the framework like a present is to lay the dome over on its side (do not attempt this with non-geodesic buildings!). This allows us to place the tarp on the top without using a ladder which we postulate are fairly rare in Haiti at this hour. The base pentagon is no more stable than any other polygon (besides the triangle), so we brace the base pentagon with two 13-foot 2 X 4s fabricated from 4 boards temporarily borrowed from another kit. This triangulates the pentagon into three triangles thereby allowing us to flip the dome on its side with no structural impairment. The dome is rolled along the ground over a stretched out tarp and tightened and nailed to the frame as we go. Later, I will cover the pattern for tightening and tucking in the extra 5 pentagons worth of material on the top. Stay tuned…