Bob,
I have NOT used Sunbrella for over twenty years now. it loses it waterproofness after a year. It stretches, it deforms & it breaks down. it ALSO has NO wear properties.
I have used laminated, plasticizing products for years. It's a laminate product & they don't leak and/or stretch. If you use a brand with rip-stop threading, they will double the life of what you are using now with Sunbrella. I first saw this material as window coverings on BIG sport fisherman yachts.
Look around, as my last 3 materials were a laminated synthetic. The secret, is going with a canvas maker that KNOWS how to stitch/use this material. Some will say they do not work with these composition fabrics, so find one that does.
I can say, that my last 3 Biminis have lasted an average of 8-9 years on average. In the middle, I've had to re-thread, as industry standard stitching is not what you want to use. There IS a stitch material that has UV resistant properties unlike the standard run-of-the-mill types. You need just doing your due-diligence to find it.
Here's a partial pic of my latest bimini. It was not made as good as I had hoped, it wasn't the fabric, but rather the seamstress. Hopefully, it will give you something to think about.
CR
