What Type of Framing Material Should I Use to Build My Backyard Greenhouse?

When considering purchasing a greenhouse kit to add a greenhouse to your backyard, one of the most important things you should think about is the framing material.

The framing is the backbone of your greenhouse.  It should be strong, weather resistant, yet lightweight and flexible.  Greenhouse framing can be made out of an assortment of materials and which one you choose should be based on your use of the greenhouse, your local weather conditions and your budget.

First of all, the most important consideration when choosing a framing material for your greenhouse is your climate.  Do you have a humid climate or is it dry?  Do you experience large variations in temperature from summer to winter?  How much rainfall does your area average.  All of these conditions must be taken under consideration when deciding what framing material to choose.

In areas that get a lot of rainfall, it is best to consider a synthetic framing material, like pvc, plastic or polycarbonate.  Each of these materials is weather resistant in ways that wood and steel or aluminum could never be.  PVC, plastic and polycarbonate will not rust, splinter, rot, or otherwise breakdown in the elements.  One of the major drawbacks to using a synthetic framing material is availability.  Synthetic materials may not be readily available in all areas, and having them brought in may add a significant amount to an already expensive bill.

A good alternative to synthetics is metal framing materials.  Metals offer a strong frame for your backyard greenhouse and while wet climates may cause rusting, metal framing materials will actually outperform their synthetic counterparts in hotter, more arid climates.  Aluminum and steel framing will better withstand the expansion and contraction of hot, arid conditions better than synthetic materials, which may be prone to breakage over time.  Because there is little water in the environment, there is little threat of rust or weathering of the metals.

The drawback to either of these solutions is cost.  Both synthetic and metal framing materials are considerable more expensive than wood.  This is partly due to the fact that they will generally last longer than wood, but if cost is a concern, a well sealed, pressure treated wood frame will last for many years.  Wood is readily available in all markets and is the easiest material to work with out of all the materials available.  Wood can be cut and shaped to fit any application and is biodegradable for those who wish to keep their greenhouses “green”.

No matter which framing material you choose, make sure that your kit allows for that type of framing material.  It is unwise to attempt to substitute one material for another, unless your blueprints allow such a substitution.  This will ensure that all the included hardware works properly, that the pieces all work together and that the greenhouse will actually be able to stand the test of time.