This week I spent 3 half-days at (farmer) friend Colin’s place in the Fulford Valley, helping with the installation of his first (of two) 25’ X 60’ Sliptube mobile greenhouse. Sliptube is based in Surrey, BC and builds all types of fabric-covered volumes including aircraft hangars.
I showed up 3 or 4 hours into the first day. With 4 guys on the job, the steel skid foundation was set in place and a couple of ~2.5” steel arched-trusses were connected at one end. The design seems straightforward: heavy gauge steel, appropriate bracing, rugged connections. The odd glitch was quickly resolved by company rep Bob. By lunch time on the third day, the house was essentially complete. Colin’s first assigned task for it will be for the chickens to start munching on the wireworms that lurk below the surface of the recently disked soil.
Next week the crew minus Bob and me will construct (farmer) friend Zak’s identical unit. Then back to Colin’s for his second one. These guys both have a ton of experience in agriculture so it’s both encouraging that, like me, they’re investing in greenhouse space… and discouraging, since they plan to grow the same crop varieties in theirs as I do in mine even though island demand for these crops won’t necessarily increase, at least not at current prices. Sigh.
Would I invest in such a greenhouse product? Well, I would like to, I suppose, but I just can’t quite commit to the outlay until I’m convinced I can sell everything I plan to grow. The cost per square foot of this unit approaches $5 and ~5 minutes of construction labour. The large PVC/poly tunnel I built also came in at about 5 minutes/sf of construction labour but only about $1.25/sf of materials. On the other hand, I’m still not sure whether the tunnels I built will withstand our snow load even though this design has done so in Saanich for a few years. Also, I can’t drag my tunnels to new ground like they can theirs. Finally, theirs have more volume due to the higher ceiling that using steel permits.
Guess we’ll see what happens over time.