We do recommend ordering your cover with either 1.5 lb foam or 2 lb foam for extra strength. If your cover is under an awning or a gazebo then the 1 lb foam will be sufficient. Covers built with 1 lb foam tend not to be strong enough to sufficiently withstand the outdoor elements for the long term. For example here is a 4" to 2" tapered cover with the 1 lb foam after the winter thaw (picture shown is not one of our covers).
1. Foam Thickness: We offer three foam densities. 4” to 2” taper, 5” to 3” taper and a 6” to 4” taper. The thicker the cover the more insulation it offers the spa. We recommend for climates with moderate to harsh winter conditions to order a 5” to 3” taper of thicker.
2. Foam Density: The higher the foam weight the denser the foam which will give greater strength. 1 lb foam will hold 40-45 lbs of weight, 1.5 lb foam will hold 70-80 lbs of weight and the 2 lb foam will hold over 100 lbs. The thicker (taper) the cover the greater the weight bearing as well. Example: 6" to 4" taper with 2 lb foam will hold 250 lbs+.