The glass and frame are actually only part of your greenhouse, which you count on to provide an artificial climate.

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Heater, ventilators, humidifiers, and perhaps a cooling system, must be considered in almost all greenhouse operations. Requirements will vary with each house, depending on location and nature of the crop or crops to be grown.

One critical part of your greenhouse, as it is with any type of building, is your greenhouse foundation. You must ensure the greenhouse foundation is sturdy and solid.

A strong foundation will ensure your greenhouse is protected from its own weight, any strong winds which may blow, and if you live in a cold climate, ice. The materials you can build the foundation with include: concrete, cement, cinder blocks, or even Transite. Not only will these building materials ensure you have a solid foundation, they will provide excellent insulation to protect your greenhouse from losing heat. A very important factor, if you are paying to heat your greenhouse.

You can build the frame from many different types of material. You can construct the frame with aluminium, redwood (highly recommended, due to the fact it's naturally rot resistant.) or even cypress.

Of course, aluminium will cost you more to use in the construction of your greenhouse. The advantage to aluminium is that you won't have to put much time or cost into maintenance. To make life easier when constructing the greenhouse, you can buy the wood or aluminium with pre-cut grooves. This will enable the installation and construction a much easier task.

Glass, Fiberglas, or plastic such as polyethylene, are materials used for greenhouse light; 20- to 30-inch panes are preferable. One of the most popular prefabs comes with 24- by 30-inch lights. You don't have to splurge on the top, Grade A, glass. You can save yourself some money by purchasing double thick Grade B glass. Older greenhouse publications will tell you that you really shouldn't use anything but Grade A glass. However, double thick Grade B has proven the test of time as being economical and sturdy.