I am considering adding styrofoam insulation board to my hot tub. I am wondering if there might be a reason not to do this. I drop around 9 *F from 102 in 24 hours. Maintaining 102 requires 2 hrs of heating per day (70 day, 45 night).
My new tub is an Infinity bought from Costco. I have read lots of criticism of this brand on other forums. Much of it seems to be from dealers upset about the low prices available from Costco.
I recently saw a TV show, “How They Make It”, and the tub they manufactured had a lot more foamed on insulation than my tub has and had vents “for the heat from the pumps” which I do not have. I do have aluminized bubble wrap insulation at the side walls.
The tub sits on deck joists that are at ground level. Unfortunately I did not put any foam insulation boards under the tub. I can only add insulation on top of the plywood bottom of the tub. Moving the tub to put insulation under it would require cutting the power conduit.
350 gal Infinity using BBB