I think Harbor Freight still makes those silver-grey tarps that should have more reflective quality keeping the inside surface cooler. Also should be more opaque than the blue ones...blocking more uv.
> I ordered some coated nylon from Defenders to make a sun cover
> for my Coastal, but once I saw the stuff I decided it was too heavy
> and too dark and would get too hot in the sun.

> So I have just thrown a cheap blue plastic tarp over the boat.
>

> Anyone know what the UV protective characteristices of a cheap
> blue plastic tarp are? I have my kayak on a rack under a very wide
> aluminum canoe, so it only gets sun for about three hours in the morning
> most days.