Courtesy of James K., Virtually Green, San Francisco, CA
A peaked high tunnel design helps reduce problems with snow loading, as well as with condensation drip from the interior apex curve of half-hemisphere shaped high tunnels. A good size go start with is 30′ x 40′.
For those of you considering building high tunnels that are large and to last for a good number of seasons you should consider making your high tunnel out of steel pipe. There are a number of good steel pipe hoop bending tools out there that make the job easy and quick. You end up with a strong greenhouse that has the structural strength to handle attachment of interior fans, shades and lights (within reason).
You might modify any high tunnel design to bend half hoops instead of full hoops, with the last couple feet of each half hoop being straight to attach to a ridge beam and create a peaked roof. A peaked roof also makes it easier to build in ceiling vents if you need the ventilation in hot weather.
You might also consider straight sides and straight roof, using the pipe bender just to bend the wall- roof elbow (at the top of the sides and bottom of the roof): this increases the interior greenhouse air volume a bit and makes the interior edges of your planting area a bit easier to work.
CONTINUE THIS DISCUSSION ON DIY HIGH TUNNELS IN THE FORUM > > >
FIND OUT OTHER WAYS TO JUMPSTART A BUSINESS GROWING FOOD FROM THOSE WHO ARE OUT THERE DOING IT EVERY DAY WITH A MEMBERSHIP TO BACKYARD RICHES HERE.
