Shrink Wrapped PVC 3V? Good Enough For Me!
OK So that might be a bit cryptic for the uninitiated but you have to admit its catchy! It refers to the the frequency (number and arrangement of the geodesic triangles) of the geodesic biodome greenhouse I am planning.
I have decided on using PVC water pipe as the strut material and bolts at the connections rather than any of the commercial dome connectors available online. (Note the price for each connector! And for a “full” kit of connectors and pipes at over $500.00. Yikes!) That’s why I chose to go the DIY way. Plus its more fun!
This brings me to the latest information I have uncovered. When choosing a cover for ones dome there are many factors to consider. In my case and in many peoples, the prime consideration is cost. So the question I sought to answer was what material will have a decent half life, be easy to apply, waterproof light and cost effective? The absolute cheapest way of course is to salvage some used clear plastic off another greenhouse and drape it over your frame, weight it down with rocks and off you go. Cost: potentially free.
But because I am a dyed in the wool geodome geek I wanted something a bit sexier than that and also I want to be able to easily move my greenhouse if needed. Plus I don’t want to mess around with dirty old plastic either. Bear in mind when growing in warm climates one needs a top vent and it will be harder to seal with the draped plastic cover. So… I chose to go with industrial shrink wrap! You may have seen this used on construction projects to protect workers doing exterior work on scaffolding. A fun thing I have seen in Europe is that the building under reconstruction is recreated on the shrink wrap so that when you walk down the street the building is “still there” even though it is completely covered.
Anyway the whole idea of shrink wrap got me excited because it should be relatively inexpensive, easy for the do it yourselfer and with some creativity should provide a double layer capability for insulation too. So when I spotted a phone number on a shrink wrapped boat I called up and got Hugh on the phone. Surprise! A nice guy running a one man show.
He said the clear shrink wrap will tighten up by 25% when heated with the applicator gun, seal to itself and last 5-7 years in direct sun. All for $125 bucks for a roll that would do my 8ft geodesic dome several times over. So when I finally get the frame built I will do a complete cover (except for the door and vent) of clear shrink wrap then use some spacer material along each strut and do another layer to make an insulating air gap. Viola! Waterproof, insulative, clear, light, fast AND sexy! The perfect cover for my little PVC 3V. The next question is should I buy my own heat gun or rent one? Stay tuned!