Attaching Film to Greenhouse Frame

I'm building a wood framed greenhouse, and I'd like to know the best way to attach the plastic film to the frame. Also, should I use treated or untreated lumber (presumably when I'm done it will be weather tight but I'm concerned about the humidity inside)

We stapled the plastic to our GH frame and then screwed
1 1/2" wood laths over that so no air can ever get under the plastic.
I live in a cold area and when the cold air hits the warm plastic it causes a lot of condensation which drips down the plastic. We used pressure treated 4"x4"'s for the floor frame.

I'd go with treated wood, especially for the ground contact areas. When you staple the plastic to the wood use some batten tape or the like to keep the plastic from pulling off of the staples.

You gonna do a double-layer plastic, and inflate it? That will sure help in the long run.

Thanks Horseshoe and snowhermit for the info. I was going to staple it and then rip some treated 2X4's into 1X2's and screw those down on the seams and other places where the plastic contacts the frame. I wasn't sure if the chemicals in the treated lumber were bad for the plants. I've been reading though and the consensus seems to be that treated lumber doesn't hurt the plants. Although there seems to some argument over whether the chemicals are bad for humans.

I read a snipit about double layering the plastic and inflating it. Does it help regulate the temperature?

Do either of you know anything about the PVC framed greenhouses? I found a design for a quonset hut type greenhouse made from PVC. I understand that they sway like crazy in the wind. I was thinking of building one and reinforcing the ends with 4X4 posts (sunk in the ground and about 4 feet high) to stabilze it. And using 1" to 1.5" PVC to make one that's fairly sturdy (and about 20X24 feet).

Thanks,
Fletch

I'm not familiar with the PVC ones. Mine is made from pipe that can be bought at Home Depot. You can see the treated 4 x 4's in this picture and the stabilizer bars we put in on the sides and back to keep it from moving. There are holes drilled in the floor beams and rebar put through and hammered into the ground so it can never blow away.

I'd go with metal ribs also, rather than pvc, especially for a greenhouse that size you mentioned, fletch. In your area I'm assuming you're in a windy place, and also you'll want to consider any snow load. Your wood-framed ghouse would be much more sturdier than pvc. (Maybe you could build a pvc "hoop house" in a smaller fashion and try it out in your garden area to extend the crop season, then see how that works before you try building a larger ghouse of the same fashion.
As for double-layer plastic, yep..it makes a big difference. Really helps to hold in the heat and also cuts way down on condensation.

Snowhermit, NICE looking greenhouse (nice Brugs too!) Mine nevers looks as neatly organized as yours does!

snowhermit and horseshoe,

Thanks for for advice and information. I think I'm going to use the galvanized metal pipe instead of PVC. I do get some wind where I live and I don't think the PVC will be sturdy enough. Definitely not for winter.

snowhermit - that's a pretty nice GH. What are it's dimension's? What diameter pipe did you use? And how did you attach the pipe cross braces?

I just joined DG a few days ago, the advice and information available here is just incredible!

Fletch

Fletch, Our GH started off being a 12x20. Last year we added another 15 feet to make it 12x35 and attached it to the house so I would'nt have to trudge through ice and snow to get to it.
We used 1/2" conduit pipe and 3/4" for the ridgepole.It is attached to the wood with pipe clips.The cross pipes on the side are attached to the 1/2" conduit with plastic cable ties.