I have a few questions and ideas for you. How big of a greenhouse do you want, how often do you intend to move it and what kind of equipment do you have to move it with? I do also realize that the need to be built on skids May have more to do with building codes or restrictions for you so you may not actually plan to move it at all.
I made my garage on skids, it’s 16x24’ 1.5 stories tall. I used a cribbing of 6x12 beams to build on. It’s technically movable, but it’s something you’d only want to move once. It can be moved by a bulldozer or excavator, but really it was only built on skids like this to satisfy terms of a
land lease.
I build saunas for people, typically 8x12 or 8x16’ and these are always built on skids. I either use 6x6” or 8x8” timber and I dovetail in crossmembers to hold the beams together. Then I just build on top of that with typical construction methods. I run the exterior plywood sheathing down to the skids, leaving it about 1” from the bottom of the skid. This helps tie the building to the skid. Use additional strapping if necessary to help make sure the building stays attached to the skid. Put cross bracing in the walls, cause being a greenhouse you will probably only use plywood for the first 4feet up from the bottom of the skid. Cut an angle on the front and back of the beams to make pulling easier. If you really want it slick, bolt some UHMW plastic strips to the bottom of the skids. Once the skid is assembled and you have the plywood sheeting and strapping securely fastened, you can bore a 1 1/2” hole or so through each end of each skid. Put a piece of steel pipe in each hole to protect the
wood, then you can run a cable or chain through each skid and pull it. You could put one pipe that goes through both skids, but I’ve found these are more prone to bend if you try to pull it from just the middle of the pipe. I do better using 2 8” pipes and running chain or cable to each skid. Just make sure you have sufficient crossmembers in the skid or you will just pull the two skids together and the whole thing will fall over. Don’t rely on nails holding a few 2x4s to the top of the skid to do the job. They need to be in between, not on top of the skid. If you use 8x8, use 4x4’s or something for your cross bracing. You will only have 4 inches of clearance, so build accordingly. Use taller skids if you are going to need more ground clearance.
Another option if you only need to move it back and forth is to use a frame like a high tunnel. There is a track made from angle iron that is just laid out or staked in the ground, and the hoop tunnel rolls back and forth over the crops. If you built a floor into your hoop and put on end walls, you have an enclosed greenhouse.
All in all, I think it’s a very doable concept, but I would personally limit it to a 12’ wide greenhouse and maybe 16’ long and use plastic instead of real glass. Maybe only wood to the top of the grow beds, then a hoop house on top to make it a little lighter, but I’m not sure about your snow or wind conditions you will be facing in Alberta. You may need it to be more structural and have polycarbonate panels. Put in a
wood stove and you’re in business.
T-
3
