GREENHOUSE ALERT

GREENHOUSE  ALERT

WARNING REGARDING PLASTIC MATERIAL FAILURE

Sorry for not posting much for a while, didn't have much new info but I just found a problem I thought you should know about.
My greenhouse was built in 2012 and I thought the plastic vapour barrier I used to cover it would be good for at least 5 or 6 years as the material I used at our previous residence had been in use for at least 5 or 6 years and it was still in good condition when we moved.  It appears to be still in use there now!
HOWEVER - when I was in the greenhouse the other day I looked up and noticed the plastic on the roof is breaking down, has holes in it!  I have checked and it is "normal" vapour barrier with UV inhibitors in it so - maybe there has been a change in regulations as to what or how much inhibitor is now in it.

In any case, I am sure it will last over the summer and if not, then it can just let some rain into the greenhouse - no problem!

My next step was to check and see if there were different qualities of vapour barrier.  I could NOT find any information to show there may be different plastics/inhibitors etc.

SO - what to do?  I thought about using corrugated clear fiberglass panels.  Seemed like the smart thing to do.  But there is always a "catch" - something to watch for.  
The panels come in two weights/thicknesses.  
The lightweight would cost about $150 plus cross strips for the corrugations to fit into and support it.  From what I see on some blogs this material is too light and cracks very easily - to the point of being hard to handle without breaking it.
The heavy weight would cost about $350 plus cross strips.

The alternative is to replace what is there with the same poor stuff.  The cost of a 59 foot roll by 102 inches wide is about $40 plus tax.
This means I could re-cover the roof three times with one roll.  I think the walls will hold up a little longer than the roof as they don't get the sun beating on the as badly as the roof does.  

So - it looks like I buy the $40 roll - works out to about $15 per covering which is much more bearable than the expensive fiberglass panels.

Next I am going to have to do some research into the vapour barrier that is available to see if there is something out there somewhere that will last longer than 2 years.  It USED to last longer!!!

Could it be that the manufacturers like it to break down sooner so they can sell more?  NO NO NO!  The wouldn't do that would they?