Saving money by doing things yourself is the hottest trend in home improvement. So it's no surprise that there are a burgeoning number of self-made greenhouse plans on the market today. These plans allow people to build their own greenhouses out of inexpensive materials that can be purchased in any big box hardware store. If you've thought about building your own greenhouse, here are some things to keep in mind.
Materials will make up your biggest expense when building a greenhouse. Inexpensive materials include schedule 80 PVC pipe coloured grey or black, rebar, 2X4 wooden planks, copper wire, gopher wire, a large black rain barrel, soil mix to feed the beds, construction plastic a hammer, nails, a staple gun and construction staples or U-nails.
Construct your raised beds first, using 2X4's to frame in the beds. This will give you something to attach the plastic to when you place it over the greenhouse frame. Cover the foundation with gopher wire to prevent burrowing animals from invading your greenhouse. Next, drive rebar into the ground around the perimeter of the frame. Bend your PVC pipe frame into large half-circle shapes. Place the ends of each pipe rib into the rebar to hold it in place. At the ridge of your greenhouse, wire the pipes together for stability. Frame up a door for each end of the greenhouse. The doors must fit the frame tightly in order to keep the greenhouse sealed when closed and prevent the wind from blowing the cover off of the greenhouse. However, when they are open they will vent the greenhouse. Place the black rain barrel in the centre of the greenhouse to serve as a thermal mass. This will absorb heat in the daytime and distribute it in the greenhouse at night.
The reason for using construction plastic initially is that the plasticisers in the PVC pipe will react to the heat in the greenhouse, causing the plastic cover to deteriorate. After the first year, it is safe to replace your plastic covering with a heavier, greenhouse plastic.