My S&G has been stored outside for 2 years now. I re-sewed a car cover so it is able to completely wrap around the yak. Velcro tabs sewn in help to hold it all together. Don't use Tarps, they are not UV resistant enough. I think my covers made out of Tyvek (no squirrels here!). The car cover came with ventilation flaps down the center which lined up perfectly with my cockpit and hatches.

Some problems have occurred.
1. The cover is not totally waterproof and rainwater does sit in the cockpit after a heavy shower, although it also dries out fast.
2. After 2 years the covers near the end of its life and is starting to grow a new skin out of duct tape.
3. The main problem is the variation in temperatures. The epoxy on the deck has started to "crack" where the curve is the most extreme. The epoxy doesn't show any sign of UV damage (7 coats of varnish over it) but I think the different expansion / contraction rates of the ply and epoxy has caused the cracks. My deck is not fibreglassed at all, just a couple coats of epoxy. I will be sanding the epoxy off and glassing the deck before summer.

Cheers
GrantG