Published Oct 6, 2015

Workshop Recap: High Tunnel Build at Prairie Sky Farm

By Liz Kolbe

We had a small but mighty group of people at the high tunnel build Sept. 3-4 at Prairie Sky Farm. Even in 95+ degree heat, the crew of attendees, led by Adam Montri (check out his six PFI farminars Feb 2010, Jan 2011,  Jan 25 2011Dec 2011, Feb 2012, and Jan 2013) worked hard over the two days to complete the high tunnel… and learn every step of the process.

Below are 19 videos of a few important steps (descriptions are below each video). Many more photos and details to come – stay tuned to the blog!


Usually ground posts are pounded in by hand (remember the plug/cap!). We used a skid steer to push them down. The post level was crucial for this.


The group lifts a completed bow and sets it into the ground posts.


Attaching the hip boards required one person to hold the screw head with locking pliers until the bolt was “sucked through” the channel.


They get the right tools, finish the first hip board bands.


A small, steel plate with a pre-drilled (by us) hole stabilizes the hip board connections.


Adam discusses variations on the baseboard, hip board, and roll-up bar.


After constructing the endwalls on the ground, the group lifted, and shifted them into position.


Purlins were measured and marked on the ground to help level the bows. In this video someone on the ground helps check that the marks on the purlins are lined up with the bows. Purlins are attached with two stirrup braces.


The window vents on the endwalls were lifted using the bucket. Remember to have all the hardware ready before you get it up there!


Adam uses a jig saw to cut extra poly from the door frame (we then fitted the extra piece to fill in the space above). Later, we used a grinder to cut poly and aluminum. A Sawzall was used to cut steel.


Bob uses an angle grinder to trim the poly and aluminum poly-fasteners.


After the aluminum tape is covering the poly, flashing is run along the edge of the high tunnel and snipped (to bend) at joints. The wiggle wire channel will lay over the top of the flashing. (Note, the bottom piece did tuck under the top piece, in the end).


Adam discusses high tunnel plastic specs after rolling it out to cut.


Five ropes were thrown over the high tunnel to pull over the plastic.


Tennis balls were tied to the plastic (clove hitch or miller’s knot, etc). With five to a side, the plastic was guided and pulled over the tunnel.


All hands were on deck to pull the plastic over the high tunnel… and then… the camera fell over.


Wiggle wire is used to hold the plastic at the end walls, hip boards, and roll-up bars. Here, we are working the wiggle wire into the roll up bars (Hip boards first, then endwalls, then roll-up bars).


A tension rope was run through hooks and eye bolts on the outside of the roll-up bar to prevent the plastic from billowing in the wind when rolled down.


Steel stoppers were attached to the back of the door and top of the door frame. More Tek screws!