When To Replace Your Hot Tub Cover
Here at St. Lawrence Pools, we get a lot of questions about hot tub covers. In this article we will go over everything you need to know about hot tub covers including how to know when it’s time to change the cover, what to look for in a new cover and how to properly maintain the cover to get the longest life out of it.
When is it time to replace a hot tub cover?
With new covers costing hundreds of dollars but the inefficiency of an old cover potentially costing much more, knowing when to replace a hot tub cover can be tricky. Hot tub covers generally have a lifespan of around 4-5 years, however, UV radiation from the sun, falling debris (like tree branches or ice) and user inflicted damage (usually from attempting to remove snow and ice buildup) can all drastically decrease the life of your cover.
Most of the time hot tub covers will need to be replaced because their foam cores have become saturated with water. Over time the plastic vapour barrier wrap around the foam deteriorates and the foam begins to absorb water. Foam insulation works by trapping warm air within the bubbles of the foam. As covers become saturated and those air bubbles fill with water the cover will lose it’s ability to insulate effectively, causing a dramatic increase in your monthly electric bill. Unlike air, water is a very poor insulator. In fact, water transfers heat 32 times faster than air! If it’s not replaced the cover eventually becomes too heavy to lift and will either cause damage to your cover lifter or split along the stitched seam that holds the two halves of the cover together.
If the corners of your hot tub cover begin to lift like this it can no longer form a good seal and should be replaced.
In some cases, hot tub covers can also start to “cup” when they are subjected to heavy loads, most commonly from snow or ice. If you notice the corners of your cover start to lift off of the shell of the hot tub you should consider replacing the cover. A cupped hot tub cover will cause a big increase in energy consumption as it breaks the seal around the edge of the hot tub, allowing a substantial amount of steam and (more importantly) heat to escape.
What to look for when buying a new cover
So now that it’s time to replace the hot tub cover, what do you look for? Knowing what cover to purchase can be tricky as there are many different options available, as well as a wide range of quality and price.
The first thing to do when looking for a new hot tub cover is to look at how thick the vinyl is, how thick the cover itself is, and to check the quality of the stitching as these are usually the first things that are neglected on cheap covers. Cheap, thin vinyl will rapidly degrade from the UV of the sun and poor stitching can result in the cover ripping, even under normal use.
When it comes to thickness, the thicker the cover, the better it will insulate. Covers generally range from 3″-2″ thick up to 6″-4″ thick. Thicker covers are also heavier however. Once they start to become waterlogged they will tend to put added stress on the seam of the cover when sitting on a cover lifter and will rip sooner than a thinner cover. The added insulating ability of the thicker cover can therefore negated by having to buy a new cover sooner. Overall, we’ve found that covers between 4″-3″ and 5″-4″ thick tend work best if the hot tub has a cover lifter.
Another thing to consider when buying a hot tub cover is the “foam density”. The higher the density of the foam, the better the insulating value of the foam, and the stronger the cover will be. While the added insulating value of higher foam densities is not very significant, the added strength can be a big plus if you experience heavy snowfalls, or if there is a chance of pets or children climbing on the cover (which is still not recommended). Covers are generally offered with a foam density between 1-2lbs, with 1lb being the standard for most retailers.
Thermal images of a hot tub cover with, and without, a full foam sealer. Notice the difference of over 18 degrees when a full foam sealer is added!
Some common extras you can get for covers are a full foam sealer (also known as a full hinge seal or centre seal), aluminum backing for the foam to help strengthen the centre of the cover (and help prevent cupping under heavy loads), and upgraded vapour barrier wrap around the foam.
A full foam sealer is a piece of insulating foam that fills the area between the two sides of the cover. Without a full foam sealer the cover will have a 1″ gap that is un-insulated when it is closed. Many covers come standard with two small (~4″) pieces of foam on either end of the cover or a rubber bar. These are only really useful for preventing evaporation and offer almost no real insulation.
The vapour barrier around the insulating foam will typically range in thickness from 2ml to 10ml. The thicker the vapour barrier, the better it will stop water from absorbing into the foam, and the longer it will last before deteriorating. Most replacement hot tub covers come with a 2ml vapour barrier wrap as standard.
Overall, when choosing a hot tub cover it is very important to look at how the cover is constructed and what is being included in the price of the cover. Simply buying the cheapest cover can cost you big money on your electric bill, or cause you to have to buy a new cover quicker. Spending as little as $30-$50 more on a hot tub cover can make a big difference in the lifespan of the cover and, more importantly, your monthly energy costs.
Alternatives to traditional hot tub covers
Here at St Lawrence Pools, we offer two viable alternatives to traditional vinyl hot tub covers. Like vinyl covers, the first alternative is custom made to fit your hot tub. They are made of aluminum and thick polymer panels, which leads to a much stronger cover that will not cup or break from heavier loads. The foam insulation will also not absorb water like in a vinyl hot tub cover, leading to a much longer life.
Automatic hot tub cover like this offer the longest life and best insulation of any hot tub cover but are also the most expensive option.
The second alternative is an automatic hot tub cover. These are also made from aluminum and thick polymers, but are styled like a gazebo and will work for hot tubs within a set size range. They offer automatic opening and closing of the cover, lighting, shades and bug screens. They also have a rubber gasket that extends around the edge of the hot tub to provide the best seal, and the most foam, to give the best overall insulation of any hot tub cover available.
Extending the life of your hot tub cover
We’ll end this entry with some quick tips on how to extend the life of your hot tub cover.
- Keep the cover clipped in to prevent it being potentially carried off and damaged by high winds. This will also help to form a better seal, reducing the amount of heat loss, and increasing the energy efficiency of the hot tub.
- Avoid resting anything heavy on your cover, remove any heavy loads of snow or ice in the winter. When removing snow off of a cover don’t use a shovel. Shovel blades can catch on the cover and tear the vinyl, leading to the cover rapidly becoming waterlogged. The brushes used for cleaning the snow off of car windows work well, as long as there isn’t any ice built up.
- To reduce stress on the centre seam of the cover while it’s on a cover lifter you can purchase specially designed nylon straps. These straps attach to the centre bar of the coverlifter and extend to brackets that support the weight of the cover.
- Leave your cover fully open for at least 30 minutes after shocking your hot tub. After you shock the hot tub, strong chemical vapours are released that can harm the underside of the cover, and increase the rate at which the vapour barrier deteriorates.
- If the hot tub does not have a cover lifter, use the cover’s handles when taking the cover on and off of the hot tub. This will greatly reduce wear on the seams of the cover, and prevent them tearing from improper handling.
- Clean your cover using a UV protecting spray at 2-4 times a year to help reduce the harmful effects of the sun on the vinyl finish and stitching. If possible, position your hot tub in a shaded area of your backyard.
- Try to avoid placing your hot tub directly under the eaves troughs of your home. In the winter, icicles will form and eventually drop onto your cover, potentially causing damage to the cover.
- As with any part of the hot tub, make sure that you properly balance the water to ensure that you get the longest possible life out of your cover. Acidic water can stretch out the fabric of the underside of the cover, and consistently high levels of chlorine or bromine can degrade the fabric and foam.
With anywhere from 30-40% of the heat loss in a hot tub coming from the cover, making sure that the cover is working at peak capacity should be a top priority for every hot tub owner. Along with being harder to handle, broken, cupped, or saturated hot tub covers can cost you hundreds, or even thousands of dollars in heat loss. Knowing when to replace your cover, and what to look for in a new cover are vital in ensuring the best energy efficiency for your hot tub. Paying a little more upfront for things like full foam sealers, vapour barrier upgrades, or higher foam densities can pay dividends over the life of the cover, increasing energy savings, and extending the life of the cover itself.
That’s it for this entry, if you liked what you read please share it with your friends and family on Facebook, Google Plus, Pinterest, or Twitter! You can also like or follow us on any of those to get notified when we post new entries. If you have any further questions about hot tub cover replacement, or any other hot tub related inquiries, please e-mail us at firstname.lastname@example.org or come by one of our four locations and see one of our hot tub experts.
If you would like a quote on a replacement cover for your hot tub see our hot tub covers page.