Materials

• You have a choice of several materials when building a greenhouse. Aluminum, galvanized steel and wood make excellent choices for the frame. Glass is the traditional covering material, but other choices exist. For gardeners concerned about dealing with any broken glass, fiberglass, a tough material that can resist hailstorms, is a good option. Acrylic plastic and polycarbonate plastic coverings retain heat and provide energy savings. The West Virginia University Extension recommends using a permanent concrete foundation, comparable to a home foundation.
  
  

Heating

• A greenhouse gives the gardener the ability to control temperature in the growing environment. The best temperature for a greenhouse depends on the type of plants grown, the site and how much sun the structure receives. Although heat from the sun can provide part of the structure's heating needs, it also requires an internal heating system. Electric heating systems and gas and oil heaters all make good choices. Wood heating can also work well. Solar heating panels, however, are not cost effective, according to the West Virginia University Extension
  
  

Pests

• Because of the temperature conditions, greenhouses provide favorable conditions for the spread of pests. Gardeners must constantly watch for insect activity and inspect any plants brought into the greenhouse for pests. They should also make sure any soil or potting media is free of insects and regularly clean all tools and equipment. A clean weed-free environment inhibits insect population growth. Use pesticides with caution, as the enclosed space makes the chemicals even more potent than normal. Contact your local county extension for information on the safe use of pesticides in greenhouses.
  
  

Attached or Freestanding

• You can attach a greenhouse to another building or make it as a freestanding structure. Some of the advantages of an attached greenhouse include the availability of the water and heating systems of the main building. However, an attached structure will have sunlight limitations, as the primary building blocks some of the natural light. Freestanding buildings have the advantage of receiving sunlight from all sides, but they typically require separate heating and watering systems.