Need Roofing Advice

whoose · July 9, 2020

I used a product called polycarb on my greenhouse roof and installed 5 years ago and last year a hail storm damaged it. Yesterday another hail storm destroyed it. The roof is set up for 5 feet by 26 inch pannels. Any advice on a product that might last a little longer? I had old fiberglass (yellow) with poor light transmission for 30 years and it never failed.
The poor light transmission made me change.
Help with specific products/experiences please.
Thanks

biscuitridge · July 9, 2020

I've used twinwall polycarbonate panels before, they lasted 20 years before hail destroyed it.

Cole_Robbie · July 14, 2020

I could never bring myself to pay the outrageous prices for panels. If it were me, I would probably frame it for 6 mil poly film and attach the film to the frame. You can do a double layer if the space between is ventilated.

We tend to think of poly film as not being strong. If you take a razor blade to it, of course it isn't. But I would dare say that film would outperform panels in a hail storm. The film gets to move when the hailstone strikes it, and that takes force off the impact. The film on my high tunnel survived 90 mph winds. In ice and snow storms, it is the strength of the film that brings down a hoophouse, because it won't break. My chain link top rail structure went down that way, but the clearspan building next to it stayed up, holding I would guess about 4,000 pounds of snow and ice over its 48 foot length. My poly film was rated 3 to 5 years, and I got six out of it.

July 9, 2020	#1
whoose Tomatovillian™ Join Date: Mar 2015 Location: Bozeman, Montana Zone 6b Posts: 333	Need Roofing Advice I used a product called polycarb on my greenhouse roof and installed 5 years ago and last year a hail storm damaged it. Yesterday another hail storm destroyed it. The roof is set up for 5 feet by 26 inch pannels. Any advice on a product that might last a little longer? I had old fiberglass (yellow) with poor light transmission for 30 years and it never failed. The poor light transmission made me change. Help with specific products/experiences please. Thanks

July 9, 2020	#2
biscuitridge Tomatovillian™ Join Date: Jan 2014 Location: washington Posts: 498	I've used twinwall polycarbonate panels before, they lasted 20 years before hail destroyed it.

July 14, 2020	#3
Cole_Robbie Tomatovillian™ Join Date: Jun 2012 Location: Illinois, zone 6 Posts: 8,407	I could never bring myself to pay the outrageous prices for panels. If it were me, I would probably frame it for 6 mil poly film and attach the film to the frame. You can do a double layer if the space between is ventilated. We tend to think of poly film as not being strong. If you take a razor blade to it, of course it isn't. But I would dare say that film would outperform panels in a hail storm. The film gets to move when the hailstone strikes it, and that takes force off the impact. The film on my high tunnel survived 90 mph winds. In ice and snow storms, it is the strength of the film that brings down a hoophouse, because it won't break. My chain link top rail structure went down that way, but the clearspan building next to it stayed up, holding I would guess about 4,000 pounds of snow and ice over its 48 foot length. My poly film was rated 3 to 5 years, and I got six out of it.