Greenhouse frames can be made of aluminum, plastic (resin), wood, PVC, or Solexx. Frames begin with a galvanized steel base or sometimes a wood base. The quality and strength of the frame determines what and how long the structure can endure.
You can build your own greenhouse frames or buy kits that contain all the materials and connectors needed. Wood is a popular choice for DIY projects because it’s easy to work with and versatile for many different styles of design. Wood does have the potential to become diseased and hurt the plants though – especially avoid pressure-treated lumber because it contains toxic levels of arsenic which get into the wood during the treatment process.
Greenhouse frames are often made of aluminum, which doesn’t rust and is relatively inexpensive. Aluminum detractors look down on aluminum because it doesn’t stand up to the strongest wind or the hardest snow. Aluminum also doesn’t insulate.
