Why Do Hot Tub Covers Get Heavy? | Northern Hot Tub Covers®

19th Jun 2019

If you own a hot tub long enough, eventually you will start to notice that the hot tub cover is getting heavier. Today, we will take a look at why this happens, why it is bad, and what you can do to prevent it from happening to your hot tub cover.

Why Do Hot Tub Covers Get Heavy?

Hot tub covers become heavy when they become waterlogged. While hot tub cover foam is covered in a plastic vapour barrier to prevent water absorption, this isn't a perfect solution. Over time, the vapour barrier will either get punctured or simply deteriorate on its own. Once this happens, steam from the hot tub and rainwater will begin to absorb into the foam, causing it to become heavier and heavier.

What's Bad About Having A Waterlogged Hot Tub Cover?

Foam insulation works by trapping warm air within the bubbles of the foam. Waterlogged hot tub covers are a problem for one simple reason, water is a terrible insulator. In fact, water transfers heat 32 times faster than air! Once water starts to fill up the air pockets in the foam, the insulating ability of the cover will begin to rapidly diminish. This leads to a dramatic increase in your monthly electric bill, especially in the winter.

How To Fix A Heavy Hot Tub Cover

To fix a waterlogged hot tub cover you need to dry out the foam. While this may sound easy, the reality is often different. Depending on how waterlogged the hot tub cover is, drying out the foam can take multiple days, making this impractical in cool weather and impossible in the winter. If the vapour barrier has deteriorated, the dry cover will quickly start to absorb water again anyway and can become completely saturated again in a matter of a few weeks or months.

If the cover became waterlogged because the vapour barrier was pierced by something, you should be able to repair it (assuming the weather is warm outside), otherwise, replacing the hot tub cover is likely the best course of action. For more information on how to properly dry out a hot tub cover, see our hot tub repair guide.

How To Prevent A Heavy Hot Tub Cover

While you can never really prevent a hot tub cover from becoming waterlogged, you can slow down this process greatly by buying a cover with a thick vapour barrier.

Vapour barriers in replacement hot tub covers typically range in thickness from 2ml to 12ml. The thicker the vapour barrier, the better it will stop water from absorbing into the foam, and the longer it will last before deteriorating. Although upgrading to a thick 10-12ml vapour barrier will set you back $35 or more, it can add months or even years to the lifespan of your new hot tub cover; making it money very well spent.

Wrapping Up

Eventually, every hot tub cover will get waterlogged and need to be replaced. If your hot tub cover became waterlogged due to a pierce in the vapour barrier, you may be able to fix it by drying the foam out and repairing the hole in the vapour barrier, otherwise, you are likely better off simply buying a new hot tub cover. While this might sound extreme, the energy savings that a new cover will provide will far outweigh the costs of replacing your waterlogged hot tub cover. widget logo

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