Greenhouse kits to build your own dome garden.
We’re all over greenhouses this year because it’s top on our gardening wish list. Most gardeners we hear from would love to be able to extend their growing season, and even grow food year round! We love the idea of being able to grow things like avocados and dwarf citrus and other milder climate fruit trees, plus year-round fresh herbs, greens and veggies. So we definitely plan to invest in multiple greenhouses over time.
We’re intrigued by the concept of a geodesic greenhouse dome, so we were glad to be able to learn from this article on domes and greenhouse kits. We asked the owner of Geodesic Dome Greenhouses, James Freed, how it is for growing year round.
“Depends on how your greenhouse is equipped. We have grown all year here (in Alaska) with additional lighting and heat sources in winter and had the dome outfitted for climate. A standard model in Alaska will extend your growing season from March to the end of October without added heat and lighting.” James Freed, GeodesicDomeGreenhouses.com1)http://geodesicdomegreenhouses.com/
Geodesic Dome Greenhouses
Article by GardensAll contributor, James Freed, of GeodesicDomeGreenhouses.com
Why domes? Geodesic dome greenhouses are an efficient design for creating an optimum environment for growing in both cold and warm climates. Whether it’s an arctic climate in winter, or something milder, you can actually grow year round in a dome greenhouse.
Our geodesic dome greenhouse kits and designs range from 15 to 100 feet in diameter and up to 50 feet high and use the best in solar greenhouse technology.
Designed for both tropical and cold hardy plants, our greenhouse kits are unique, robust garden structures, made from eco treated wood struts and metal or schedule 80 Poly hubs and covered by reinforced polyethylene.
Families, schools, after school programs and community centers are using greenhouse kits to allow families and communities to grow fruits, vegetables, flowers and even trees, though supplemental heat and lighting may be needed, depending on your zone. Besides allowing you to grow organic food year round, these domes create a green oasis in the middle of winter.
A gardener’s favorite winter hangout.
Benefits of Geodesic Dome Greenhouse Kits
STRENGTH: The first greenhouse kit design feature is, of course, the shape of the geodesic dome. While it is a beautifully shaped building, its real beauty lies in its strength. The triangle shapes forming the geodesic dome creates a geometric pattern of strength not replicated in a simple rectangular shape. With designs for roof top growing for cities, geodesic greenhouses are the best structures for wind, seismic, and snow. Adaptable to any scenario, you can choose greenhouse domes large enough for community gardens. The dome design is much more efficient than high tunnel cold frames, and dome greenhouses are now approved for the USDA NRCS High Tunnel Program.
WIND: The geodesic dome greenhouse is incredibly wind friendly as the wind simply flows around it. A rectangular greenhouse has a much larger surface area for the wind shear and outward thrust to push against.
SNOW: The round shape also handles snow effortlessly because it allows snow to slide off naturally, so there’s rarely, if ever, that much snow pushing down on the green house. The geodesic structure is immensely strong, as it is made of triangles: the most rigid shape. Our Arctic Domes have a snow rope on a swivel, standard on larger models for easy clearance.
SOLAR INPUT: The curved surface of the geodesic dome allow for a very even heat input by the sun throughout the day. A rectangular greenhouse has a large flat area sloping south allowing a larger amount of sunlight to come in at mid-day, whereas in the early morning and late afternoon the light input is negligible. With diffusion and refraction from multiple triangulations, light is dispersed throughout the structure.
ENERGY EFFICIENCY: Heat loss from any structure is proportional to the surface area of the structure. A spherical shape has the minimum surface area for the amount of floor space enclosed. The geodesic dome is much more effective at keeping the heat in on a cold winter night simply by having 40% less surface area than a rectangular structure. This reduced surface area also keeps the dome greenhouses cooler in hotter climates.
Heating and cooling are up to 40% more efficient.
The Benefits of Polyethylene over Polycarbonate
Why polyethylene instead of polycarbonate, and which is the most cost effective?
It would seem that polycarbonate, a strong, rigid greenhouse plastic, would offer the best insulating factor for your greenhouse. It is the standard greenhouse covering, here in the United States. However, science has proven how thick polyethylene plastic engineered with enclosed bubbles of air insulates better than polycarbonate.
Conduction and Convection Heat
To understand the physics at work, remember that:
• Conduction is heating by contact
• Convection is heat transfer by the movement of a liquid or gas
• Hot air or hot liquid rises to the top of the space it is in
Air conducts heat very poorly, however air transfers heat or moves heat through the space convection-wise, very well. Air will hold heat in the space it occupies. If this is a large space, the hot air will rise and remain at the top of the space. If the air is in a small space, there is less of a distance between the hot and cold spaces, this will not allow the air to separate very well.
The lighter a material is, the better insulating properties it has. The denser the material, the faster it transmits heat and the faster it loses heat, as well. Glass, being denser than polycarbonate, loses heat faster than any other greenhouse covering in comparison.
In Ianto Evans’ book “Rocket Mass Heaters” he states:
“To delay heat moving by conduction, a good rule of thumb is to choose the most lightweight material available.”
“When a greenhouse plastic is lightweight, it usually means there is air trapped in it. A down parka, sheep’s wool socks or a fiber-filled bed quilt all contribute to our comfort by trapping air, one of the most effective insulating possibilities known.”
Conduction always flows from hotter to colder.
Polycarbonate is a rigid, dense plastic. It quickly conducts heat from inside a greenhouse to the outside. Polyethylene is much more lightweight so it slows the heat transfer. When the polyethylene has air bubbles engineered into its design, the heat transfer is slowed down even more, making it thermally more resistant to temperature changes.
Polycarbonate may seem to be able to insulate better. However, due to the properties of heat, and the way it behaves when transferring through different materials, we can see that polycarbonate will insulate less and lose heat faster than polyethylene greenhouse film. Polyethylene, or PE, designed, as a greenhouse plastic constructed with air bubbles is an energy saver.
Imminent Innovations for Improved Insulation
Soon we will be manufacturing a two layer 20 mil beehive hexagonal polyethylene cover called Arctic Wrap that will be available worldwide. Geodesic Dome Greenhouses have many options for warmer and colder climates. For colder climates, we equip our dome greenhouse kits with a 12 mil layer of reinforced polyethylene creating a great biosphere for growing all year round.
Geodesic Dome Greenhouse Kits have designs that meet or exceed even Anchorage Alaska building codes. Geodesic Dome Greenhouses has a great tower growing plan where a family can provide fresh vegetables for your local box store throughout the year. Where return of investment is usually less than one year. We install on larger projects across the nation and Canada. Our Domes can be shipped worldwide. Geodesic Dome Greenhouses is committed to keeping prices reasonable while providing a quality product. We assist in facilitating community gardens with products donated to us and disburse to those in need when available. We also have school programs where schools provide wholesome fresh foods for cafeteria and for sale. Raising revenue for school while saving food purchases.
How Long Does it Take to Build a Geodesic Dome with a Greenhouse Kit?
Small 15-20 foot domes take 1-2 days for home installs. It is good to have a carpenter there to speed things along especially on larger projects. The large 40 footers have taken 4-7 days, depending on how much help and amount of time dedicated each day.
We are creating a video that will accompany each dome with step-by-step instructions to help self install customers. Meanwhile, we make ourselves available, even on Sundays. Once we open a new manufacturing place in Missouri, we’ll have a installation supervisor on call for questions as well.
Next is a brief video tour of the inside of one of the dome greenhouses in Alaska, followed by more photos.
For more on other kinds of greenhouses, you may also enjoy these articles:
Contributor Bio: Jim Freed
I am a journeyman carpenter. I literally fell into the dome greenhouse business when I fell off a ladder. While resting and rehabbing an injured shoulder. A friend asked if I could build them a dome greenhouse, knowing that I had built two dome homes in the past. I agreed. The word spread as others saw the dome greenhouse and wanted one too. The rest is history. My wife Jami is the gardener. She loves to grow food and medicinal herbs. We both have the passion to help schools, communities and individuals become more reliant in self and localize food. Plus the ability in this unstable economy to have a product all want and need: food! With tower gardening in conjunction of domes. A family can make a great living growing food. For more information, contact James Freed of Geodesic Dome Greenhouse Kits.4)http://domegreenhouses.com/
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