Solartuff- uv rays/painting in summer

[daemondamian]

I'm examining various materials that could be used for a greenhouse. There is a product called Solartuff which is a polycarbonate roofing sheet that comes in either the Roman or Greca profile and clear, has a 10 year life time warranty on it.

It also says it has 99.9% UV protection. Here's the datasheet on it http://www.laserlite.com.au/products.../datasheet.htm

What I'm wondering is how much UV plants in particular orchids do require, or do most GH coverings/glazings [shadecloth, glass etc] cut out a lot of the UV anyway?

Also if one were to use a clear polycarbonate like this in the roof, could it be painted in summer just like glass GH's [in addition to shadecloth] are to reduce the light and heat?

Any thoughts or advice would be appreciated

[Ray]

From what I've read, orchids don't really need UV, so feel free to use the stuff.

Personally, I recommend against painting polycarb. It is a plastic, so is actually porous, and the paint can stay in those pores a lot longer than you want. You also have to remember that the UV protection is on the outer surface of the sheets, and you don't want to do anything to potentially damage the coating.

If you are using shade cloth and aren't getting enough shade, get a denser weave or use multiple layers.

[daemondamian]

Originally Posted by Ray

From what I've read, orchids don't really need UV, so feel free to use the stuff.

Personally, I recommend against painting polycarb. It is a plastic, so is actually porous, and the paint can stay in those pores a lot longer than you want. You also have to remember that the UV protection is on the outer surface of the sheets, and you don't want to do anything to potentially damage the coating.

If you are using shade cloth and aren't getting enough shade, get a denser weave or use multiple layers.

Thanks Ray for your reply

I would never have thought about the plastic being porous and paint staying in the pores [and building up, blocking light unless you scrubbed the polycarb which could damage it also] or possibly damaging the UV coat.