The UnderCover is a protective barrier that creates and maintains a dry space directly under the spa cover, keeping your foam cover light.

Drains Without Letting Vapor Hit The Foam Cover.

At the center of each panel side is a drainage system, which collects accumulated water, and drains it back into the hot tub. The drainage system includes a funnel made of PVC film, feeding into a p-trap style drain which bars water vapor from moving up into the foam.

The p-trap concept, used in plumbing, is applied to a ½ inch bolt, with an acorn nut. Holes are drilled through to bolt head, and through the bolt’s length. Water moves through the bolt head, down through the length of the bolt, into the acorn nut. Threads in the bolt are sheared off on 2 sides, to allow the water to move up between the bolt and the acorn nut where it finally spill out the top of the nut, back into the hot tub tub. By moving the water this way, water vapor is barred from moving into the space between the UnderCover and the Spa Cover, while allowing any trapped water to drain.

Up until now, there hasn’t been a spa blanket worth noting that attaches directly to the spa cover, because such a system would cause mold without being able to drain. As soon as a hole is made for a drain, the spa blanket becomes redundant, since water vapor would be able to move freely into the spa cover. With this new application of a widely used backflow prevention principle, the spa owner is able to enjoy a lighter spa cover without extra effort.

Fastens Right onto the Spa Cover.

Standard Spa blankets are cut to fit directly on top of the water. When the jets come on, the standard blanket gets shoved over, made useless. The UnderCover attaches directly onto the spa cover; nothing’s displacing it.

Premium polyethylene spa blankets have good insulation properties, but they rapidly deteriorate. Resting on the water, they’re subject to a constant barrage of chemicals and hot water; they’re literally designed to be replaced every year. The UnderCover’s made entirely of corrosion resistant, heavy duty PVC. It’s made to last and maintain your cover’s insulation.

Fasten & Forget.

With standard spa blankets, every time you need to use your spa, you have to wrestle a sopping wet blanket out of the water. During the winter, that soaking wet spa blanket will freeze, and then likely thrown aside and abandoned.

The UnderCover is easily fastened to the cover, permamently. Forget dragging a sopping wet blanket off your spa, just fasten, forget, and enjoy the benefits.

Highly Durable.

The exterior film of the UnderCover is made of a highly reinforced PVC film, usually used in industry for various liquid containment application. Featuring a tough synthetic woven fabric, coated on each side with a heavy layer of polyethylene plastic, your spa cover will be protected as never before.

Custom Made

The UnderCover is made to be able to fit any hot tub cover, and is easily, and quickly, installed. Detailed instructions come with each order.