After fixing my hot tub and repairing the leaks, I needed a new hot tub cover, but of course, they were difficult to find after COVID and the era of remote work. Many shops were either closed, or way behind on their orders. The quotes I received were both extra expensive and usually had wait times of 6 months or more! So I decided to try making my own, thinking it would get me by for a few months, until things got back to normal.
It has now been over 3 years, and I am happy to report that I'm still using that cover! It has been working pretty well. Because of its modular design, I have been able to change out the parts that tend to wear out. The heavy duty plastic mattress bags that I got from Home Depot needed replacing after about 2 years. The plastic was starting to get brittle and was tearing in some places. So I bought 2 new mattress bags and new Tyvek tape to seal them back up. Once I started removing the old plastic, they started to rip even easier, so you definitely don't want to let those go too long, or you might have bits of plastic in your hot tub!
I also used that time to dry out the foam. I'm in California, and it was not rainy season, so there was no problem giving them some sunshine and drying them out. Much like the pro covers, the foam did absorb some water and they got a little heavier over the years. Not too bad though. I had also considered using my dehumidifier, but opted for a week or 2 of dry winds and sunshine.
And I've just been using 9x9 foot heavy duty poly tarps from Home Depot for about $17 each. They come with a rope that I pulled tight and tied a knot, and worked great as a weather cover, easily allowing one of the 4x8 foot foam pieces to flip over onto the other, much like the pro covers. Unfortunately, these particular tarps last only about a year for me before they start to disintegrate. I initially bought 3, since they seemed to work so well, but once I realized they break down, I started putting another cheaper tarp on top when I was out of town, knowing it would benefit from less exposure to the sun and wind, and in the winter time, rain. I also put sandbags on the corners when I'd leave town, since I often get winds from 30 - 60 MPH, and sometimes higher. It seems to stay put, but the sandbags on the corners give some extra piece of mind that it won't blow away.
So what would I do differently? I could probably just buy a pro cover again, but I've been pretty happy with mine. It insulates well, and works pretty well too. It doesn't look perfect, and I'm not sure how it might work with a cover lifter, but it works for me. If I remake the foam, I would make a wire foam cutter so I could cut a better angle on a full 4x8 sheet of foam. I made mine with a saw, which was a mess! I worked with 2-foot sections to make the cutting a little easier, but they have warped slightly differently, and they were kind of a pain to glue them individually. Other than that, I would just buy a marine-grade vinyl tarp, which should last much longer. The 9 x 9 foot tarp size works perfectly for my hot tub, which is two 4 x 8 foot sheets of foam. But like I said, those poly tarps (even heavy duty) are pretty much disintegrating in 1 year. So kind of gross if that plastic and dye gets into your spa, or goes around your yard. And also NOT environmentally friendly!
My total cost in early 2022 was about $189, all from Home Depot:
3) 4 x 8 foot 2-inch foam sheets - $135
2) Heavy-Duty Mattress Bags - $25 (replaced after about 2 years)
1) Roll of Tyvek tape - $12
1) Heavy-duty 2-sided poly tarp -$17 (though I bought 3, and replaced each year)
