[Heat Loss Through Cover Hinge?]

I agree I don't want a big blue tarp flowing out if the tub, but I read here and elsewhere it is usual to replace the cover about every 3-5 years due to failures caused by heat and moisture. Thats a $300+ expense I would like to at least see happen les often. Any ideas why a simple vapor barrier (plastic) will not help?

[Heat Loss Through Cover Hinge?]

My wife asked me why we cannot put a tarp or plastic sheeting UNDER the hot tub cover to keep moisture damage to the cover to a minimum? I know the spa blankets appear NOT to be airtight, they seem to address the issue of temperature only. I did not have an answer for her, any help?