What type of plastic? With such a small building, I am going to guess that you used plastic from the hardware store. If this is the case, the problem is the plastic, not the PVC. The plastic from the hardware store doesn't have the UV inhibitors and will break down after several months.

I have greenhouse plastic that is on a PVC hoop building for two years and I don't have a problem.

Just my two cents.

Jay

You want to check the owner's manual for the greenhouse film you purchase - some (e.g. IIRC Tufflite IV) won't warranty touching PVC.

But the solar UV likely broke down the plastic if it was only several months.

Dan

Dan,

Yes it does say that and I am not concerned about warranty. I discussed this with other growers who use PVC on small tunnels and they have had their plastic on the PVC for 6 years and they don't have or haven't seen a problem.

I think the out-gassing is an issue if the plastic is brand new. I usually leave mine outside in the sun. The places I have bought it from store it outside and I just haven't seen the issue with it.

Regardless, we usually get some wicked hail around these parts and I am more concerned with hail than the PVC touching the plastic.

One way around this is to paint the PVC. I didn't take the time.

Jay

Thanks Jay and Dan. This is what I want is you 2 cents worth.

I bought my plastic at Home Depot or Lowes in the construction dept. 6 mill. 100' foot role.

If you were to paint the PVC, what color would you use?
I did try some weather sill stripping. The stuff you put on top of blocks before you start putting up your walls, pink and blue in color.
That was wrapped aroung the PVC. They both broke down about the some time.

More input please.

gmom

You could paint it white. Less heat absorption against the plastic. But I wouldn't bother painting it.

That plastic film is the problem, not the PVC. Builders plastic has no UV stabilizers. You need greenhouse plastic.

Dan

The builders plastic looks so appealing. Trust me, I was in the same boat as you the first year I built a small hoop house. I thought plastic was plastic. Why do I need to pay the added shipping and cost. I didn't listen to other. Now I understand. That 6 mil greenhouse plastic is some amazing stuff. If you are going to the expense to build it, skin it with the good stuff. You won't regret it. There are many places that carry the stuff. This year I will have over 3,000 square feet under plastic this year.

IF you paint, I would go for some plain white. Better yet, check out the mismatched, wrong color paint section. Same paint, just cheaper.

The sill tape doesn't have UV stabilizers either.

Jay

Habitat has white paint for cheap.

Where I used to live in Western WA there were plenty of folk with the PVC hoops and they were persnickety about their plastic, so perhaps the best advice is to go with the folks in the area who rave about theirs. You can't go to HD and paint that 6 mil painters' plastic and have it last. We all found that out the hard way.

Dan

You can get from HD self adhesive aluminum tape to put on the PVC. They will last forever.

The tape is not expensive. they are the same size as duct tape.

dcarch

Good point arch - I looked at HD and alum tape was ~12.99, I went to Harbor Freight and got it for 7.99 a roll (this past fall). Should bring up again that 1/2" EMT conduit is about the same price as PVC and will last far longer. You can make your own bender out of scrap plywood and 2x4s.

Dan