Geodesic Domes Construction

Wood is a tried and true building material. It's been used practically since man left the cave if not before. Wood is much less expensive than metal.

It absorbs and holds heat which helps regulate the temperature of your greenhouse.

Wood is not as strong as metal and isn't considered as long lasting but if properly cared for can last a really long time. (There are wooden structures still in use today that are several hundred years old)

Most wood used for construction will need to be treated in some way. Paint or stain to seal out moisture and protect it from insect damage.

Redwood... Redwood has a lovely color and a natural resistance to rot, insects and moisture damage. It requires very little maintenance because it doesn't need paint or stain to protect it. This makes redwood frames very popular for geodesic dome greenhouse construction. And many greenhouse kits come with redwood frames.

Cedar.... Cedar is another popular choice for geodesic dome frames because it is also naturally resistant to rot and insect damage. Not quite as resistant to moisture as Redwood you may want to paint or stain a cedar frame making it more effort to use and more costly in the long term as touch ups will mean more maintenance work you your part.

Other woods... Geodesic greenhouse (and other greenhouse) frames made from other woods will need to be treated with a preservative like Copper Naphthenate (which is not harmful to plants) then paint or stain to protect it from rot and insect damage. Though this may make "generic" wood like 2X4's undesirable when you consider availability, ease of use and cost, this is the choice of may frugal gardeners. And with proper care, such greenhouses can last decades.

Metal greenhouse frames are usually considered to be the strongest and most substantial of all. They are also the most expensive. They do not retain heat, they heat and cool off rapidly. This could be a problem in colder climates where heat retention is an important factor.

Aluminum... Aluminum is a light but strong geodesic construction material. It is difficult to work with for the average diy builder. Requiring special tools for cutting and joining. It is VERY resistant to moisture damage and is non-rusting. Once your aluminum greenhouse frame is completed, it needs little maintenance just clean it regularly and it will last for years.

Iron... Iron is very strong and it is also very heavy. Because of it's strength it is sometimes used for very large structures but it must be kept painted when used in a greenhouse or rust will eat it away quickly. Not easy for the average diy builder to work with and needing continual touch up painting it is not recommended you build your bio dome from iron unless you hire professionals to do it for you.

PVC is quickly catching up to wood in popularity with the diy greenhouse crowd. Light weight and easy to work with PVC is flexible and not subject to rot or insect damage.

Once covered with a rigid or soft plastic "glazing" it creates a very strong stable framework. Maintenance is a snap too... just give it a regular cleaning to get rid of dirt and algae build up.

The only draw back to pvc for geodesic dome construction is the need for special connectors or "hubs" to create the shape needed. However specialty shops and even Amazon often carry these for those of you who want to give a PVC Greenhouse a try.