There seems to be an almost total lack of understanding of structure and material strength and durability.

You seem to lack bsic knowledge of structural mechanics. The wind godsare always unkind. I used to work in factory which had asbestos sheetsabout 1/2 inch thick and about 10 x 5 ft in length and breath. Duringa mild strom we had, they were just blown away like thin sheets ofpaper. The steel bolts were just wrenched off. Asbestos sheets weighing about 50 pounds each were no match in a mild wind strom.A plastic sheet 20 feet in length will make a good wind sail. You willhave to buck up on your knowledge of material science.

pep and sand, I think you've been too hard on Artz. The idea of a great-big piece of stuff to cover a whole roof isn't new and it isn't bad--there are plenty of products like roll-roofing and different kinds of continuous mats and they sort-of solve tough problems in an easy way. It's just that they're asphalt or rubber or fiberglass, not plastic. And they have a frame under them for strength.

But I've designed 1/2" thick plastic (acrylic) bubbles for food machine hoppers that span four-feet and are domed and they operated at very high-vacuums with tremendous stress. They were really heavy, too, so I have little doubt that they could survive a wind. But a 4-foot dia piece of 1/2" plastic costs $400 before you form it. This would be unlikely to ever be cost effective for a roof. Also, they don't bend appreciably, so they won't roll-up.

Also, artz has forgotten that sunlight and ozone destroy plastics. I followed a '78 Fairmont in traffic a minute ago and the 30-year old taillights were dissolving before my eyes. To last, plastics need special coatings (not too far different from metals) and they need to be re-coated regularly.

I don't know what kind of vehicle you could carry a rolled product of plastic this large on -- I suspect that if you used 1/8", you'll never roll in to less than a six-foot diameter. And 20 foot 'wide' exceeds the length of my car-trailer. You'll need a semi to put a new roof on your house.

But it does sound fun. So if you can 1. pay for it, 2. get the 20 x 50 ft piece of platic to your house, then 3. form it into a dome once there, I think yes, this could be cool. But I wouldn't cut a hole for light--I'd make the whole thing clear.

It would melt like a bar of chocolate. it would warp like wet baseball cap. It would stink like taxi cab in Iraq.Try using this sheet for indoor uses. Keep thinking, you'll get it right.

As others have pointed out, there are problems with this idea. I will add that putting a single large piece of plastic on a roof may be simple, but that doesn't mean it's easy. It would literally weigh a ton. Hoisting it onto the roof and then unrolling it would be a challenge. Also, if you unroll it in the usually fashion, like a carpet, it will tend to curl up, not down. So you would have to flip it over to match an arched roof.

Another problem would be attaching it to the frame. You would have to attach it or it will blow off in high winds. If you nail it down, the holes would be potential leak hazards. One of the problems with large roof sections is that they will expand and contract a lot when heated and cooled. This puts stress on the attachment system. Nail holes will get stretched and cause leaks. You could use glue instead maybe, but it will still be stressed by expansion and may tear loose.

However, people that say you can't use recycled plastics for roofing are quite wrong. A number of companies make recycled plastic shingles.