Spa cover
Spa covers are very expensive, and very short lived, because they are made of vinyl that tears and expanded polystyrene that absorbs water. Does anyone have any with experience or thoughts on building a spa cover? I was thinking marine plywood and EPS.
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Replies
William,
You can build a cover as your propose, but the plywood will make it heavy. The advantage of vinyl is that it is light.
If you go ahead with your plan, make sure to purchase Type IX EPS. For more information on this issue, see EPS characteristics.
William,
I'd forget the plywood, it too will get saturated quickly. The real need is for a truly effective vapor barrier, on the tub side. I'd think aluminum foil with folded and taped seams (seams taped with aluminum tape) might extend the life of the foam.
William,
I do a lot of work for a nearby resort with over 20 hot tubs. They spend a fortune on hot tub lids and several years ago we tried to do what you are proposing and design a better one. We consulted with surfboard makers, and marine upholsterers with no luck.
The problem as far as we could see is that if you manage to design a cover robust enough not to be broken or deteriorate, it is either too heavy or damages the hot tub itself. If you can come up with something I'd love to hear your ideas.
The tubs I'm dealing with are gunite and are in ground, so I was thinking my homemade covers could have wheels if the plywood makes them too heavy.
I've been told that using Lemon Pledge on a spa cover makes a big difference if the cover normally sits in the sun. Our friend on Texas Gulf coast said he went from getting a new cover every year to lasting more than five by wiping it down regularly with Pledge. (Bi-weekly? Can't remember...) Might be worth a try until you come up a better cover.
Would a fiberglass layup over EPS or XPS work, like a surfboard, light and waterproof, and you could paint it. I don't know if sanitizers would affect it but probably not it painter with marine epoxy.
I don't know anything about this product. High density urethane comes in sheets of all different widths and thicknesses. http://precisionboard.com/pdf/PBLT-4-DataSheet.pdf
William, If the tub's finish won't be affected I'd make a fibreglass coated one. We only rejected the prototype the surfboard maker made because it wrecked the tub gelcoat.