There are basically three components to a greenhouse. You have the frame, the glazing material or covering and the greenhouse supplies.
· Greenhouse Framing -If you are building your own frame, most people will choose wood due to the availability. You can use regular 2 x 4's or treated lumber. With the new pressure treated lumber you do not have any issues with compatibility of the glazing materials. If you have access to aluminum or steel, they are also acceptable materials. Sometimes you may have a local sunroom company that will supply you with aluminum extrusions. Local welding shops may be willing to work with you on a steel frame.
· Glazing materials - There are a lot of different choices here. Also, a lot of different price points. I will discuss these from the least expensive to the most expensive. First there is 4 year, 6 mil polyfilm. This is UV protected for longevity. The name is somewhat misleading. You may get 4 years out of it, but mostly this is referring to the length the UV protection is going to last. Next is the reinforced polyfilm. This is basically 2 layers of film with a reinforced cord between. This is a rip stop feature. If the film is torn, it will not continue to tear past the cord. It will last much longer than the 4 year, 6 mil film. Next is Solexx. This is a twinwall polyethylene material. The UV coating is not applied to the top of this material, rather it becomes part of the Solexx in manufacturing. It has a 10 year warranty. It will give you a much better insulation factor than either of the films. It is soft and may be rolled to be shipped UPS. The final greenhouse glazing material is polycarbonate. It is also a twinwall or multiwall material. There are many widths and specialty sheets available to cut down on heat, etc. This is a rigid material and must be crated and shipped on a truck line. Also, don't let me ignore the fact that many people will recycle old windows to build their greenhouse.
· Greenhouse Supplies - A greenhouse will not function properly without several supplies or accessories. The two most important ones are ventilation packages and heaters. The greenhouse will need some type of system to move hot air out in the summer months. This is typically done with roof vents, exhaust fans and intake shutters. A greenhouse will not maintain heat on its own on winter nights. There are some solar methods that will assist, but usually you will need an actual heater to keep the heat at the desired temperatures. There are many other supplies for your greenhouse which may be added as needed such as, shade cloth, benches, misting systems, etc.
Don't be intimidated by the thought of building your own greenhouse. There are many advantages to building your own over buying a greenhouse kit. You can design it to fit your needs exactly. Do a little studying of the different materials available and get out there and get busy. You will get many hours of enjoyment from doing this project and ultimately, your new greenhouse.
