Sunday, 6 November 2016

HOW I MADE A GREENHOUSE FROM A GEODOME!


Most of us want to eat food that not only wet our appetite but also deliver to our body the vitamins and minerals it needs.
We also want this to be inexpensive, am I right?

For a lot of us to satisfy our vegetable needs, we have turned to gardening. I myself started this only a few years ago as the next logical step to both living a more frugal life but also a more sustainable one.

The issue

So then you may ask "what's the issue"?
The answer is "Time". Now I am not talking about time as in my hectic work schedule. I find the best way to unwind after a tough day in the rat race is to go out to the garden and play. The time that I am talking about is the length of the growing season.

As you may be aware, I live in Central Ontario. In my area we have a average last frost date around the 15th of May and a an average first frost around the 5th of October. This gives me roughly 143 days or 20 weeks of growing season.

Now yes, some things like root veggies can handle the frost and kale can even take freezing temps but the progress of these types is very slow.

So how do extend my growing season without moving further south?

Season extension

There are a few different ways to attempt season extension. The first one is something many gardeners do nearly every year. They start some seeds inside. In some cases this is the only way to get a plentiful harvest of tomatoes and peppers. Some people even go as far as to have a grow room complete with lights so they can grow things indoors all year long.

Another way to extend your season is to use low tunnels or cold frames.

Cold Frame after planting 24 Oct 15
As you can see my cold frame is just a raised bed with a cover. With this setup I was able to grow Kale an Beets all winter even though I had some -30 C (-22 F) overnight temperatures. Doing this just involved taking a blanket out and covering it on the really cold days. Using Poly for this isn't ideal as it has zero r-value. Glass would be better, but I had a roll of vapour barrier already and it is a lot cheaper.

Of course you can go full tilt and get a greenhouse but to a cheapskate like me that just wasn't an option until I read something about Geo Domes.

My frugal greenhouse

You may be asking yourself "What the heck is a Geo Dome"?
Well I first stumbled on to these a couple of years back and sort of got enthralled by the possibility. However, even though I pride myself as a general handyman the angles that needed to be cut and the difficulty of the connections had kept me at a standstill. That was until Mrs. Smallsteps... mentioned that maybe we should look at getting a greenhouse. After a quick search on the Internet we found good quality greenhouse with the space we wanted would run us around $2500.00. You could also find small flimsy looking ones for about $800.00. At this point I decided that I would attempt the Geo dome greenhouse as it would only cost a couple hundred dollars worth of wood. Not wanting to waste anytime as Halloween was right around the corner I jumped over to www.desertdomes.com where they have plans that could help me get started.

Angles? Who the heck likes angles.

Now I had a few options I could use PVC or lumber. This was pretty simple, I like lumber and had some scrap to start practising. After a few bad cuts I went ahead and built my first triangles. Making simultaneous 60 degree and 74 degree cuts took some getting use to but now I figure I would be comfortable making trusses if I needed to so that's good. I then started putting the triangles together to make a hexagon  and voila, I had made 1 wall or 1/5th of the walls which I then took it apart to stain and put plastic on  before putting it back together.

After that I made 3 more or 4/5 of the outer walls. I decided I would build the roof pentagon before the fifth wall as I needed to figure the door piece out and wanted it to be standing before I did. 

Going vertical!

Putting up the walls was a lot simpler than I had expected. I just leaned the first one on a 4 foot piece of rebar I had around and then set the second up the same way and screwed them together. Then it was on to the third an fourth piece and that went much the same as the first two. Before I walked away to start on the roof pentagon I installed a brace just to keep the walls from bowing too much if it became windy.

Closing off!

The roof pentagon was built from the same size triangles as the middle sections from the hexagons. Once the pentagon was complete it took a little finessing to get it to fit but with a little stretching it dropped in to place. Then I was on to the last hexagon which I needed to make a door frame in. I decided on a 29 inch door opening and started working on the walls. I built these in place and then took them off for staining and to put the plastic on. I found it much easier than trying to fit something that I prefabbed. Then I reinstalled and squared the opening.

The door was made out of 2x2`s with a 2x4 centre brace for strength. After staining and putting the plastic on I installed it and placed a jamb to stop it from over swinging and Voila! The dome was complete. Well, mostly complete.

Finishing Touches

By making the dome out of individual Triangles and then putting them together I ended up having gaps in the vapour barrier between the triangles due to the wood not perfectly aligning all the time. I fixed this by running clear tuck tape over every seam on the dome. After that I just sat back and let the sun do the work. I later went back and checked the temperature and compared it to outside. I think the pictures says it best, but the dome had a temperature 20 C (nearly 40 F) higher.


After all was said and done this project cost me roughly $302. Not all cost are accurate as I did not use all of the screws or stain that I purchased and I had the vapour barrier left over already. Not bad if I do say so myself.

If you have found this project interesting take a look at some of my other posts like Why Compost or Our Income Property Journey.

Do you have a story you want to tell, leave me a comment, I would love to hear