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Dome Greenhouses How to Build a Geodesic Dome Greenhouse

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Geodesic Dome

Text of How to Build a Geodesic Dome Greenhouse 33pages

  • Dome Greenhouses

    How to Build a Geodesic Dome Greenhouse

  • Dome Greenhouses How to Build a Geodesic Dome Greenhouse

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    Dome GreenhousesHow to Build a

    Geodesic Dome Greenhouse

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    Table of ContentsIntroductionWhy a Greenhouse?Why a Geodesic Dome?What Do I Use to Cover the Dome?My First Experience Building a Geodesic DomeDome Construction Location and Permits Geodesic Frequency 2V, 3V, 4V Tools and Supplies Cutting Struts Compound Angles Build Your Own Locking T Starting the Dome: The Pony Wall The First Row The Door The Top Vents Insulation and the North Wall Heating Installing SolaWrap

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    Introduction

    When I would receive house plants as gifts I would take them straight to my sisters house and say, Stop me from killing again!!!

    Yet I still attempted gardening outside. My back ached, I got heat exhaustion, and my fingernails were always short and dirty but I finally had a beautiful garden! Then all in one night it was gone not to the frost, insects, or wind like in years before but from the elk coming in during the night! They trampled my pumpkins and ate everything, they even peeled, yes peeled, the husks off my ripened corn and ate the cobs while they were still on the stalks!

    My next Garden was a Greenhouse Dome with Solawrap!

    Why a Garden? Why a Greenhouse Garden? Why a Greenhouse Garden Dome? Why a Greenhouse Garden Dome with Solawrap?

    Ill tell you why

    Why a Garden?

    We grow a garden to grow food that is:

    Free from food borne illness outbreak or pollutants Free from transportation costs Free from threats of unavailability Free from cancer causing chemicals, pesticides and herbicides, and GMOs Free from natural disasters half a world away Free from preservatives pumped in your fresh food and wax coatings

    And

    Best of all because

    Really fresh produce explodes with flavor!

    When you consider almost everything that comes into your home had to ride in a truck at some point, and that the increased cost of diesel fuel will be passed on to you, this will not only mean higher food costs but a rise in the cost of almost everything.

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    For an article on the rising cost of food, see these sources:

    http://www.backwoodshome.com/articles2/silveira112.html

    http://www.nytimes.com/2012/07/26/business/food-prices-to-rise-in-wake-of-severe-drought.html?_r=0

    http://www.slate.com/articles/business/moneybox/2011/02/the_invisible_food_crisis.html

    http://www.npr.org/2012/07/25/157371037/the-ripple-effect-from-rising-food-prices

    We could go on and on. Google Rising Food Costs and see what you come up with. Here in New Hampshire, last year one head of Romaine lettuce cost $1.29. It is now up to $2.39 as of Fall of 2012. But its not just the cost of produce. If you pay attention, companies are keeping the prices as usual, but downsizing product amount. A container of ice cream is down 6 or more ounces, but the price has remained constant.

    Why a Greenhouse Garden?

    Greenhouse owners dont worry about:

    weed seeds blowing in harmful insects uv rays- direct sunlight deer, raccoons, and other pests wind-constant or unexpected strong gusts lack of water or poor soil

    So they dont have the extra expense of:

    Pesticides, Tillers, Fences, Shades, Water filled tomato warmers, Weed mats, Pest control covers, Sensors or repellent, Knee pads, Soil tests, Fungicides, Seed starting kits, Frost protectors, or a Back brace!!

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    Why a Greenhouse Garden Dome?

    Dont fight forces, use them!

    -Buckminster Fuller

    Because domes are:

    Tornado and Hurricane Resistant

    Aerodynamic Resistant to Heavy Snow

    Slides off Energy Efficient

    Natural curved surface allows air and energy to circulate without obstruction Surface Area Minimalistic

    Heat has less surface area to escape through, naturally insulating Also decreases building material costs

    Build to Any Size

    Fits your space requirements Relaxing

    Its a wonderful place to hang out!

    Light Dispersing in All Directions

    With no shadows plants can grow from ground to ceiling which doubles or even quadruples your growing area

    Natural Strength

    Arches, hexagons and triangles are naturally the strongest shapes

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    Studies on the geometry of honeycomb pattern explain that no other shape can create more space with the given material. A comb of 100 g weight can hold in it up to 4 kg of honey! Producing wax is a laborious process. For each gram of wax produced, the bee needs to consume 6 to 7 grams of honey. Wow, these insects are born engineers and economists!

    http://www.benefits-of-honey.com/honeycomb-pattern.html

    The geodesic domes strength is due to the fact that triangles are very stable shapes. It is difficult to break or distort a triangle because compression at one joint is balanced by tension along the opposite side. The more triangles used in the design, the more solid the structure.

    http://www.sciencefairadventure.com/ProjectDetail.aspx?ProjectID=176

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    Domes, even those made of eggshells, are strong because they exert horizontal as well as vertical forces to resist the pressure of heavy loads. The strength of the egg is within its dome shape. No single point of the dome supports the whole weight. The weight spreads along the curved walls to the wide base, allowing the eggshells to support more weight. The staff members at the Ontario Science Centre in Toronto were successful with one unbroken egg supporting a 90 kg person. Thats a 200-pound person!

    http://www.csun.edu/~mk411573/discrepant/discrepant_event.html

    Self Supporting Structure-

    Tension pushes against each strut

    Light Weight, Flexible and Moveable

    Earthquake Resistant

    Picture a bowl turned upside down onto a bed of sand the sand may shift but the bowl remains intact.

    A dome is

    earthquake, tornado and hurricane resistant (FEMA rates them as near-absolute protection from F5 tornadoes and Category 5 Hurricanes).

    Several monolithic domes in Florida survived direct hits by Hurricane Katrina in 2005.

    Several monolithic domes were in the path of the 2005 and 2006 wildfires in Oklahoma and Texas, and survived with only slight charring of the exterior foam insulation.

    In 2003, a monolithic dome government building in Iraq survived a direct hit by a 5,000 lb (2,300 kg). bomb. The interior of the structure was totally destroyed, but the dome itself remained standing.

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    http://www.masterdomes.com/domemech.htm

    We just came through the craziest wind storm I have ever been through since living in Alaska, gusts up to 130 mph. We have no power and we

    lost four trees, but the greenhouse [dome] is unscathed! Now we know we really do have bubble wrap on steroids!

    -Kim Robuck

    The spherical structure of a dome is one of the most efficient interior atmospheres for human dwellings because air and energy are allowed to circulate without obstruction.

    This enables heating and cooling to occur naturally. Geodesic shelters have been installed in all extreme climates and temperatures and they have proven to be the most safe, effective & efficient shelter possible.

    -Donald E. Ingber

    -The Architecture of Life, Scientific American Magazine, January 1998.

    A dome has approximately one-third less surface area to the outside than a box-style structure. The curved surface of a dome provides a natural circulation of internal air.

    http://awakeproductions.ning.com/profiles/blogs/geodesic-domesfacts-n

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    Why a Solawrap Covering?

    Solawrap covering is:

    Light transmitting

    83% light transmission means your plants are getting enough light. The standard light transmission of glazed polycarbonate is 60%.

    Light diffusing

    Diffused light is the best light for your plants. Studies suggest that plants grown under diffused light finish faster than those grown under direct light. 83% light diffusion, the highest in the industry.

    Insulating

    This product is produced in Germany where they use a more accurate measurement of insulation, called thermal resistivity. It measures the temperature difference across a structure when a unit of heat energy flows through it in a unit of time, or more basically, how much does a material resist transferring temperature. The thermal resistivity of single walled polycarbonate is 8.7. Double blown polyethylene is 4.9. SolaWrap is 27.

    Long lasting

    There are greenhouses in Europe that have had the original covering of SolaWrap on for 24-30 years. We know this because each roll of SolaWrap is stamped with the production date. These 24-30 year old coverings are still being used today.

    Watertight

    The beading on the edges of SolaWrap is applied using a patented system that ensures extreme strength. The SolaWrap is then applied to structures using a patent pending PVC channel locking system. This system is watertight when installed correctly.

    Strong

    Solawrap is so strong that it can support the weight of three men even after four years of wear in Kuwait!

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    The scientists that developed Solawrap

    Flexible

    Structures made with flexible material are more able to withstand dynamic forces. Often natural forces can change direction and quickly intensify. If a structure were completely rigid, it would not be able to sustain this kind of outside pressure.

    Less expensive than glass or triple walled polycarbonate

    And

    Scientifically Constructed

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    Why bubbles?

    Polyethylene has a very low heat transfer coefficient and a fairly high specific heat capacity. Air also tends to have a low heat transfer coefficient and high specific heat capacity.

    Since both air and polyethylene have comparable specific heats, the change in the temperature of the same masses of air and plastic will occur in relatively similar manners. However, since the coefficients of heat transfer are so low, they will occur very slowly.

    Extreme temperatures travel faster through solids than gases, so locking air bubbles in Solawrap minimizes heat transfer. Air in a confined space is a good insulator because it has a tendency to resist temperature changes.

    In Solawrap each bubble takes in light, which it collects even in low lighting conditions, then refracts or bends it hitting the bubble next to it. This performs two functions

    1. Each bubble acts as an individual step within the wall slowing heat transfer. That protection is amplified by adding a layer of plastic to both sides of the film. Trapped air acts as an insulator preventing 60% to 95% of heat loss.

    2. It diffuses light, which increases plant energy production. Because Solawrap bends sunlight around corners it hits all the leaves not just the top ones. This means more leaves can photosynthesize for the plant which makes the plant grow and produce more without putting extra stress on it.

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    This diffusion is like driving in dense fog with your bright lights on. The light is scattered (diffused) making it seem like the light is coming from everywhere because the light is bouncing off the tiny water droplets in the air. The Solawrap bubbles act just like water droplets in the air between the sun and the plants diffusing the suns rays.

    My First Experience

    Building a Geodesic Dome

    During my life I have been in contact with several geodesic domes. I grew up in Flagstaff, Arizona and attended many events in the Walkup Sky Dome at Northern Arizona University, Ive watched my kids play high school sports in the Round Valley Dome in Eager, Arizona and my wife taught for ten years in the Mountain Meadows Primary School dome in Overgaard, Arizona. In each of these communities everybody was encouraged to go to the dome in the event of a natural disaster; just as the people in New Orleans were encouraged to go to the Super Dome during Hurricane Katrina.

    Ive been in the construction world most of my life and have always marveled at how

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    geodesic domes, which are the strongest man made structures on earth, are built. I never dreamed of building a geodesic dome due to the complexity of the structure. I wondered how I could ever figure the dimensions and angles that are required for such a task!

    Luckily for me, my sons in-laws decided they wanted a greenhouse dome built in their backyard. Because I had done some remodeling for them in the past they figured I could easily build them a geodesic dome. They were more sure of my ability than I was! I lived in Alaska, and they lived in New Hampshire, so I was worried that it would be a long trip that might end in disaster.

    After meeting with them, they decided they wanted a 40-foot diameter dome. I was in total shock! All this time in the back of my mind I was thinking maybe a 15-foot dome. First I thought, I cant build a 40-foot dome! Then it hit me, the only difference between a 15-foot and a 40-foot dome basically was the length of struts. So after studying the plans my son and I set out to conquer this huge task.

    Lumber isnt made like it used to be. So one of the hardest tasks to this project was to find 2x4s that were straight as possible with no twist to them. After hand picking my lumber, it was time to cut my struts to length, and cut the proper angles on each end of the strut. Each strut requires six, yes six angles (three angles on each end of the strut). Each angle has to be cut as close to the angle required as possible. After many meticulous hours of cutting my struts, we were finally ready to begin building the dome.

    I was simply amazed at how easy it was to construct this structure! As long as I stuck to the plans and used the proper strut when called for, building a geodesic dome was something I could definitely do! Three days with my son helping me after he got off work, and help here and there by other family members, we had a 40-foot dome sitting in their backyard. Now, I have built entire homes in the past and the sense of accomplishment is great. But Ive got to tell you, after completing the framework of this dome, my sense of accomplishment was unbelievable!

    Dome Construction

    Location and Permits

    The first thing to do before you begin to build your dome is to check with your local government and see what kinds of permits are required to build a dome. Since there is no foundation and these structures are portable or temporary, you may not need any permits.

    Next, select the location of your dome. You want your dome to be in the open as much as possible so it can receive all the sun that it can. Then make sure your site is level. If this means bringing in fill dirt or taking fill out, do it! Also whatever size dome you decide to build, make sure your building site is a few feet wider than the dome so

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    you can move around without tripping over any obstacles. If you want to run a water line and electrical line to the dome, do all your underground work before you start construction.

    I also highly recommend that you build a 3-foot high pony wall to put your dome on. A pony wall is a small vertical wall that you will build the actual geodesic dome on top of. This will help you when you begin to design the inside of your dome. If you plan on building grow beds in your dome this pony wall will make it easier due to its vertical nature as oppose to building against multiple angled walls. I would recommend your grow beds to be 3-feet high this way you dont have to bend over to garden! Keep in mind that whatever width of dome you decide on your dome will be half that in height. For example, if you build a 20-foot dome it will be 10-feet high, 13-feet if you add the 3-foot pony wall.

    Geodesic Frequency 2V, 3V, 4V

    So time to choose your domes frequency. Huh?! My domes frequency, what is that? A domes frequency is the term used to refer to the amount of triangles in your structure. An icosahedron is the shape of the geodesic domes we are building. The most basic frequencies are 2V, 3V, and 4V.

    A small dome only requires a 2V. This means there are only two different sizes of triangles in your layout. If you attempted to build a 40-foot diameter dome however, using the 2V frequency your triangles would be so large that you would have to use much stronger lumber to handle the span of your triangles. Plus covering these huge triangles would be next to impossible. Therefore, I would suggest not using a 2V for anything larger than an 18-foot dome.

    A 3V would work great, but the only problem with a 3V is the base of your dome wouldnt be flat. I dont suggest a 3V frequency for this reason. I would suggest using a 4V for anything larger than an 18 foot dome. I used a 4V for my first 40-foot dome. The 4V has 6 different sized struts, and the base of your dome is flat. With that said, lets start step by step and build a dome.

    http://www.simplydifferently.org/GeodesicDomeNotes?page=3#4V%20Icosahedron%20Dome

    This link will take you to an incredible dome calculator for all the different frequencies. The angles that each strut need to be cut are given in the section labeled edges/struts & bending angles. Then to get your lengths that each strut needs to be, and the number of each strut length, you simply enter the diameter of your dome and it gives you the lengths using the metric system. In order to get your lengths to feet and inches a simple conversion needs to be done. Here is an example:

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    If your dome diameter is 30 feet, then your frequency will be 4V. Your A strut length will be 3.7977. The 3 is how many feet it will be. The .7977 needs to be multiplied by 12 in order to convert it to inches. 12 X .7977= 9.5724, the 9 is how many inches you will cut. Now the .5724 left over is your fraction of an inch. You must round this to the nearest 1/16th of an inch. Below is a reference to help make this go quicker:

    1/16 = .0625 1/8 = .125 3/16 = .1875 1/4 = .250 5/16 = .3125 3/8 = .375 7/16 = .4375 1/2 = .5 9/16 = .5625 5/8 = .625 11/16 = .6875 3/4 = .75 13/16 = .8125 7/8 = .875 15/16 = .9375

    I would recommend printing your plan out in color and having it laminated, because you will be referring to it on the job site.

    Tools and Supplies

    Gather your tools first; you will need a miter saw that can cut at least a 60-degree angle. (Most of your larger saws will cut 65 degrees.) You also need a digital protractor (I found mine on-line at Amazon.com for around $40.00) because you will need to cut very precise angles.

    For example you may have to cut a 47.77 degree angle (round to the nearest 10th), you cant set your saw accurately without the protractor. I used a Dewalt miter saw that has the cutting stand. (http://www.amazon.com/DEWALT-DW723-Miter-Saw-Stand/dp/B00005RHPY ). The cutting stand was very helpful.

    To determine the amount of wood you will need for your dome, multiply the lengths by the amounts of each length you need. This will give you a rough estimate of how many linear feet you will need. If you are thrifty you can try to determine the best way to reduce waste by using different length 2X4s for different strut lengths. Youll need go to your local lumber store and pick out the straightest boards you can. This may take a while, but you will thank yourself over and over again for taking the time out. The ideal strut is straight when you look down the face of the board from one end to the other, as well as the side from one end to the other. Boards that curve either on the face or the

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    sides are not ideal, but can be bent under pressure to fit. Boards that twist like a spiral will give you the most trouble. If you can, avoid buying boards that twist even slightly. These boards do not straighten out easily, and will not fit against the other struts as you are fitting the joints together. A structure with this many angles does not need any outside factors making things more difficult.

    Cutting Struts

    You are now ready to cut your struts. The less human factor you can put into cutting and angling your struts, the better. This means the use of jigs or stops, which I will explain in more detail as we go on. Something else that you will thank yourself for is labeling every strut with its letter AS you go. The higher the frequency, the more strut lengths you need. If you label as you cut, you can accurately keep track of how many and which kind you have.

    Each strut has an angle cut on each end. Lets say your plans call for a strut 25-inches long with both ends having a 17-degree angle on them. Set your protractor against the saw to ensure your angle is correct.

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    Laying your strut flat on your saw, you would set your saw at 17 degrees on the table (dont tilt the blade). After checking and double checking, cut your first end of the strut. All you have to do is make your first cut, flip the strut over, and measure your 25-inches from long point to long point, forming a very long trapezoid.

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    If you are using a stopper, be sure to measure every once in a while to make sure you didnt bump your jig or stop too hard. Since you will have multiple length struts to cut be sure to cut all of one length before you go to the next strut length. Mark each length with the same letter as you cut, so you dont have to measure each one later on when you are putting the dome together.

    There are pros and cons to using a stop or jig. If you use one, you spend a little more time setting it up, and then save time as youre cutting because you dont have to measure over and over. However, every board you cut bumps your stopper just a little bit. This can cause your struts to be less than uniform. What you do depends on what you value. If you want to finish quickly, youre under the gun and only have a certain amount of time to finish, you may choose to use a jig. If you have time and want to be as precise as possible, you would want to use a tape measure and measure and mark each strut.

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    Now that you have all your struts cut to length with the proper angle on each end, it is now time to cut your compound angles on each end. Do this by setting your table angle to the proper degree. THIS IS IMPORTANT: Before you set your blade to the proper angle. UNPLUG YOUR SAW!! Now take your strut and set it on-edge on the saw against the back wall of the saw. Slide your strut to where it touches the blade when the blade is down. Since the end of your strut has an angle on it you will see that there is an angled gap between the blade and the strut. This allows your saw to cut the same angle that is on the end of your strut. You must adjust the angle of your blade to match the angle of the strut. If you do not do this step, you will ruin your strut and will have to cut another.

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    Compound Angles It is now time to mark the center of the edge of your strut with a pencil. Since you will be using 2 inch material, the thickness of your strut is 1 inches (not a full two inches). Divide that in half, which is of an inch. Make a mark at the end of your strut at of an inch. However, since boards are not perfectly uniform, measure each to find the exact center. If you do not do this, you will end up with arrow points that are not in the center of some boards.

    Set your table at either 60 or 54 degrees, whichever the plan calls for and make sure your blade is set at the angle of your strut. The ends with 60 degree angles are to connect into hexagons and the 54 degree ends are to connect into pentagons. Normally the A struts have one end that is a 60 degree and one end that is a 54 degree.

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    Now, plug your saw back in, bring your strut up to the blade and without cutting the strut completely through, just make enough of a cut so you know you are cutting at the center mark. This is where your jig or stop comes in. Holding your strut in place, bring up another 2x4 and gently slide your jig or stop to where it butts up with the strut. Clamp the jig or stop down so it doesnt move.

    Go back to the strut that you started cutting and make sure it didnt move. Now, go ahead and cut the angle on the strut. NOTE: Since your blade has a thickness to it, make sure you cut the mark with the edge of the blade. If you use the center of the blade, your angle could get off. You also will find that when you make that first cut, it will cut a little off your jig or stop (that is the thickness of your blade). That is what you want. If both ends of your strut call for 60 degrees, flip your strut end to end and cut the other end. Repeat this process to cut the other edge of the strut.

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    When done, your strut should have an even point on each end that kind of looks like a fence picket. If your point is even on both sides, you know it is right. If not, the tilt of your blade moved and you didnt have it locked down properly. Re-align the blade then continue.

    Your base or beginning struts only need two angles on each end, the first angle and one side of the arrow point. Since one side is on the ground or on blocks, the second side of the arrow point isnt necessary.

    I would suggest using Redwood or treated wood for the base since it will be on or close to the ground.

    Lastly, take your finished struts and run the top edge through a dado blade on your table saw. Make a 3/8 inch wide by 7/16 inch deep groove. This will help when you get ready to put the covering on your dome.

    Paint, stain or varnish your struts with whatever you want on the inside of your greenhouse. Look for stains that do not release toxic chemicals, so that your plants are chemical-free. You may need to ask your local hardware store for help. To stain, lay flat a sheet of painters plastic on your driveway or in your garage. Lay your struts out side by side. Then you can use a long-handled roller brush to quickly paint or stain many boards at the same time. As soon as that surface is dry, rotate all the boards in

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    the same direction and repeat painting with the long-handled roller brush. Repeat for as many coats as you desire. It is smart to paint or stain the same length struts in groups, so youre not mixing piles. When the struts are dry, stack them and youll be able to keep every length separated.

    Build Your Own Locking T

    Since my locking system is a tongue and groove system, you will need to make or buy the T lock. To make the T lock, cut a 2X4 the same length as your strut along with the compound miters. (two on each end to make it look like a picket post). Then set your dado blade so that your tongue is 3/8th inch deep. This locking system ties your covering into your struts with a great deal of friction.

    To make your own locking T take a 2x6 and cut it the same length as your strut then put the proper angle on both ends. Now you have a 2x6 that is pointed on both ends. Run your 2x6 through the dado blade on the table saw. Then flip your 2x6 and do the same on the other side. After accomplishing this, you will have a 2x6 with a tongue on the edge. Now with a second table saw set up with a regular blade, set the saw so that the top of your T is about inch thick. Then lay your 2x6 flat and run your wood through the saw cutting off the T. Now your 2x6 isnt quite a 2x6. Repeat the process until you run out of material, and your T locks are complete. Pre-drill your T lock so you dont split them when you fasten them to your dome. Be sure to stain and varnish your T locks since these will be out in the weather.

    If you feel overwhelmed with this step, you can go on-line and purchase the T lock from HarvestPathway.com. They sell a weatherproof, water-proof, mildew, mold and insect resistant thermally modified wood called Cambia in the T lock form. You dont have to seal, stain, or varnish this wood. Obviously, buying this product saves lots of time and in all honesty a lot of heart ache.

    Starting the Dome: The Pony Wall

    Now you are ready to start building. Whats great now is that you can put your saws away. You no longer need them. The only tools you need now are a screw gun, pipe wrench and a ratchet strap. The battery screw gun of course screws the struts together. Sometimes you will have to twist your strut to make it fit the best you can because the wood isnt perfectly straight. Your pipe wrench will assist you to straighten them as much as possible.

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    Build and insulate your 3-foot pony wall. The bottom of the pony wall will use the same sized struts as the base of the dome. Look at your plan and whatever letter is used for the bottom of the dome, use this letter for the bottom of your pony wall. The angles and lengths will be the same, but you will not need to cut the arrow points into them. Cut at least two vertical struts per side of the dome. These studs should be cut at 33 inches in order to get a 3 foot pony wall. Once the pony wall is completed you can insulate it using house insulation.

    You will be using 3-inch coated screws. I would suggest pre-drilling your struts. If not, you will split some struts. When pre-drilling, drill your holes just above where your angles begin. Try to hide your screws so they will not be exposed, and use two screws per end.

    Now you are ready to screw your base diameter together. Remember that if you want to use a big water tank (black, to absorb heat) in your dome, or anything that may be too large to get through the framework, put it in before it is too late. Once youre finished, measure from joint to joint to make sure that your base diameter is right. For example

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    if you are building a 30 foot dome you will measure from outside point to the opposite outside point and get 30 feet. It will make things easier as you build up. You want to get your joints to fit as tight as possible. But remember that wood is not perfect and it is very difficult to make every joint so that there is no gap. If you end up with gaps here and there dont worry, your dome will still fit together.

    The First Row

    The simplest way is to build your dome one row at a time. You will also realize that the structure aligns itself as you build. When you get to the point at the very top where you are tying the last struts together, you might find that one or two of the struts seem too long, THEY ARE NOT! You just have to move and manipulate the struts until they fit. DO NOT use a saw to make any adjustments. Try pushing the joint of the connected hexagon or pentagon away from the center of the dome.

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    Your dome will GROW with every strut you install. Sometimes it is difficult to get your joints to come together, in this occasion I sink a couple of screws and attach both ends of a ratchet strap to the two screws. I then ratchet the two struts till they come together.

    Depending on the size of your dome, you will need to get some scaffolding. BE SURE to get the kind with wheels you can attach to the bottom. Its so much easier to roll your scaffolding than it is to drag it.

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    The Door

    You will need to cut space for a door out and frame it in. You can use whatever size door you like. Find a spot convenient for a door that is not on the north wall. I installed my door on the south wall opposite of my water tank. Your dome will hold itself together, but try to find a spot where you cut the least amount of struts, leaving as many joints intact as possible. After you have measured and cut out the space, frame it in with 2 x 4s or 2 x 6s. Standard doors are usually 6 to 66 tall and 26 to 3 wide. Keep this in mind for your measurements unless you plan to build your own door.

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    Vents

    After the completion of your dome, you now need to decide where to put the vents or windows. I put in four, one on the east, west, north and south wall. I also framed in a ceiling vent as well so my dome would have a chimney effect in the summertime. You can go on-line and purchase automatic vent openers that are filled with bees wax and open and close automatically depending on the temperature.

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    Insulation and the North Wall Heating

    The heart and soul of a geodesic greenhouse is the reflective shield on the north wall, and the tank of water below it. For my reflective shield I used regular foil bubble wrap insulation that you can purchase at your local lumber company. Then cover the northern part of your dome with this material. Next, put a water tank or container (the size will depend on the size of dome) below your reflective shield. This creates a passive solar heating system. The concept is simple, the sun will reflect off of the foil insulation into the water warming it up during the day. When temperatures drop in the evening, the water will release all that stored heat and keep your greenhouse warm.

    Now step back and look at the awesome dome you just built!

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    Installing SolaWrap

    You now have to decide what to cover your geodesic dome with. You actually have many options. You could run to the nearest hardware store and buy a roll of 6 mm clear plastic that is very inexpensive. But you dont have a whole lot of strength in this material, and you will be changing out the plastic after one year or so, that is if the wind doesnt get to it first. Once you have applied it you will never want to go through the process again!

    You could go to a glass company and spend a ton of money! Plus glass is porous and very hard to keep clean. Not to mention the added weight to your dome and the safety issues. Plexiglas would work. Its not quite as heavy as glass, but its still very expensive and hard to keep clean. You could use a polycarbonate. This material is strong, but again it is very expensive and it yellows preventing light from entering your dome.

    There are a few polyethylene products out there designed for greenhouses. I would highly recommend a polyethylene

    material I am using called Solawrap. SolaWrap is a German made product that the Europeans have been using for over 30 years.

    It looks a lot like bubble wrap that we use for packaging in the U.S., but its much larger, and it has three layers. The outside layer is 8.5 mil, the bubbles are 5 mil and the inner layer is 3 mil. The main benefits to this superior material is that the bubbles difuse the sun in such a way that there are no hot spots in your greenhouse and your plants will grow straight up. Plus it is very strong and light weight, and the U.V. rating on it has a 5-year warranty. The bubbles provide a insulation value equal to two pane glass windows. The thermal resistivity (how slow heat escapes through a material) is 27 which is 3-5 times better than anything else on the market!

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    I personally have been inside a greenhouse in Germany that has had this product on it for 25 years! It was hard to tell the difference between the newer material and the 25-year old material. In the past you could only get Solawrap out of Germany or Canada. Now there is a distributor in the U.S. Go to SolaWrap.com for partial rolls or HarvestPathway.com for full rolls and more info and pictures of domes.

    When I covered my dome I found that I didnt have to cut Solawrap for each triangle. I noticed that I had a pattern of struts that ran parallel with each other. So I measured enough Solawrap to cover that run of triangles. Next, I set my Solawrap with a staple gun using just enough staples to keep it in place. Then I cut my next section of Solawrap to overlap what I had just laid down. Remember to lap your Solawrap just like you would roof a house with shingles. Water runs down hill so make sure your laps are laid the proper way. I did have a few triangles that needed to be covered individually.

    Be sure to install your T lock as you go. My philosophy is: If you dont have to make a penetration in your covering, dont. So I just T locked where my Solawrap

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    overlapped. If you want your dome to have T lock on all your struts, that is totally up to you.

    Congratulations on your decision to build your own geodesic dome greenhouse. I know you will enjoy your greenhouse for years to come and treasure the unique building experience for a lifetime!