Gary,
This is simply an opinion:
Sunbrella under ideal conditions has an expected life of six to eight years
here in FL where wind and sun do the damage. The six to eight years include
annual waterproofing applications. These assumptions are made when the
fabric is stretch fairly tight and is supported at least every three feet,
similiar to the supports you would see on a large bimini. I don't believe
there is enough strength in this or any other fabric to expect success with
any more of a non supported run. Any fabric will act as a sail, sails are
made of fabric, so design to protect from lifting from the wind would be
essential. Since our snow load here in FL is minimal and I have no clue as
to how heavy that stuff is I can only assume it would require a sufficient
slope to allow it to be removed easily to avoid tearing or collapse.
If color isn't important I have seen large quanities of sunbrella on ebay at
very reasonable prices. A lot of the reasonable prices had to do with color
and pattern, the most offensive were the least expensive.
I had some large curtains made of sunbrella a couple of years ago, they are
about 12' wide and 12' high each and hang vertically on my lanai. The
bottoms are weighted with a couple of pounds of lead each and they will do
some serious swaying in a light wind, moderate winds require they be closed
and heavy winds secured. They require minimal maintenance and despite the
fact they are white look good. They block the evening sun as were their
original purpose and I'd do it again but the cost of material and labor was
around 2K.
Hope this helps a little,
Mike
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