A lot of thought needs to go into selecting the right material for decking if it’s going to hold a hot tub. While it’s possible to make do with cheaper wood or aluminum decks, you should look at choosing a material that’s far better suited. So what are the options?
The best decking options for a hot tub are capped composite and capped polymer (PVC). Both composite and polymer decking have superior strength and durability when compared to traditional wooden decks. Capping provides extra strength than uncapped models and greatly improves its resistance to wear and tear.
There are many factors to consider besides strength and durability, however. This article is going to take an in-depth look at decking requirements for a hot tub, as well as what you need to know before you start to build.
What to Look for in Decking for a Hot Tub
The decking for your hut tub needs to cope with several factors, including chemicals, heat, water, and weight. And the most important consideration when choosing a decking material is safety.
Although many types of decking wood are more than strong enough to support a hot tub, you want to avoid anything that will become slippery when wet.
Softwoods have a coarse grain that can split open after drying and getting wet repeatedly, which means large splinters to walk over. Hardwoods with treatments resist water and become slippery when wet.
Though you can apply non-slip coatings of strips to the wood, these will cause deep abrasions if someone trips and falls on them. The safest solution is composite decking with grooved channels for drainage and grip.
Decking for a hot tub needs to resist:
- Water – Both splashing and condensation will make a deck slippery and dangerous when getting in and out of the tub. Water will soak into normal wood and begin to rot and weaken the material.
- Chemicals – You will need to use chemicals to treat the water and to clean the tub, and you are going to spill some of these. So, you need a decking material that will not mark or break down from exposure to salts, chlorine, and cleaning products.
- Weight – Hot tubs are heavy, but the weight of the water and its occupants dwarfs the weight of a tub. Even inflatable 2-person spas often exceed 2-thousand pounds when the water is added.
Composite decking is wood infused with plastic to create a product that is in keeping with a traditional hot tub but with more benefits. These composite and PVC boards are strong and will stand up to the load that a hot tub, full of water and people, will exert on it.
Composite decking is not porous, and it is also resistant to stains, rot, and mold growth.
Capped Composite vs Capped Polymer
Composite decking is not a new invention. For decades, composite and PVC decking has been the go-to material for its excellent drainage, grip, and appearance.
Common composite decking is made by fusing wood by-products, a pigment, and recycled plastics. This mix is pushed through an extruder and comes out as grooved planks, as with those from the manufacturer Trex.
The result is a low-maintenance decking wood of fixed color that helps save the environment and does not require repainting. PVC decking is 100% recycled plastic, which is cheaper than a blended composite and has a wider choice of colors.
Aluminum decking is much more expensive than composite boards but has a shorter life span and gets dangerously hot in the sun. 100% wooden decks require a lot of maintenance and are prone to rot and splitting.
Both PVC and composite decking have similar benefits and lifespans. And both decking materials can be manufactured as capped or uncapped materials.
Composite decking is a combination of reprocessed plastics and something called wood flour. Wood flour is a mix of wood by-products, ranging from sawdust to recycled paper. The result is a wood-like product is a strong and lasting material that is easy to machine.
Capping this composite makes the decking impervious to stain, scratches, and fading. Customers can specify the decking to better match their needs and to suit any profile. Manufacturers such as Armadillo and Timbertech from Azek can use capping to create composite boards of any color and pattern.
This means that you can have an easy-install wood-effect composite deck at a fraction of the price of natural wood decking. DecKorators is one such manufacturer with an impressive line of capped composite boards, all with long-lasting warranties.
- Appearance – Capped composites can look more realistic and vibrant than the uncapped variety. The capping comes in a wide range of colors and patterns, so you get a wider choice of styles from the same material.
- Strength – The capping process fuses a surface coating onto the board material. This ensures that there is no separation after years of walking over it.
- Rot – The capping process seals in the composite or PVC deck, preventing water from soaking in and creating a place for mold and mildew to grow.
- Stains – Capping protects the material from drink rings left by cans or coffee cups. Other stains from food, chemical spills, and paints are also easier to clean away.
- Dulling – A capped composite deck is better at coping with UV, which fades the colors in the board and degrades the glue holding it together.
- Splinters – Some composite boards can hide large splinters. Capping seals in these splinters, making it safer to walk on with bare feet.
- Sun – The sun will also heat the decking, which can become painfully hot to walk on in the summer. Composite decking is great for staying cool and preventing foot burn.
Capped Polymer (PVC)
PVC decking was the solution to the lack of colors and styles on offer with post-millennium, non-capped composite woods. Now both materials come formed as capped and non-capped, and both offer similar benefits in terms of appearance and resilience.
PVC decking is easier to cut than composite decking. Manufacturers such as Azek and Zuri promote the material as having better texture and choices of colors than real wood. Even photorealistic wood-grain capping is available, though some patterns are more delicate.
Capping PVC gives this type of decking a longer-lasting surface, helping it to compete with other composite materials. The capping process seals the texture from wear, the effects of weather, and the dulling caused by UV rays.
The best boards are those that are capped on all four sides to resist attacks from mildew, mold, and spilled spa chemicals. The incredibly long warranty durations, such as Timbertech Pro’s 30-year fade and stain guarantee, show just how confident the manufacturers are in the material.
- Appearance – Capped PVC products can look as realistic as composite or real wood decking. But without any need for re-staining or maintenance.
- Strength – Modern capped PVC decks are as strong as composite and will stand up to the same level of abuse as an infused wood.
- Rot – There is nothing to rot, and because it is capped, there is nothing for mildew or mold to cling to.
- Stains – Being 100% plastic, capped PVC decking is near impervious to stains and ring marks left by cold drinks.
- Dulling – PVC stays true to its original color for much longer than an all-wood alternative.
- Splinters – PVC decking is splinter-free, but the material can feel rough in some places. Capping helps to smooth out the entire board, making it more comfortable to walk on.
- Sun – Capped PVC and composite decking are superb at dissipating heat, though PVC decking is moderately better.
What to Know Before Building Your Deck?
You can use the estimate that your hot tub will weigh around a thousand pounds for each person the tub can hold. So, for a 6-person fixed hot tub, your decking should be strong enough to support at least 6-thousand pounds.
An average 6-person hot tub has a footprint of approximately 60 square feet. This means that your decking will have to support around 100 pounds per square foot.
Composite decking and PVC decking should both be able to cope with 5-10 times this weight. But the base of the hot tub should have the appropriate support beams and concrete foundations to prevent subsidence.
Ground-level hot tubs are easier to support, but you need to ensure that there is space beneath for water to drain away and evaporate.
Of the most well-known brands, Trex and DecKorators are at the higher end of composite and PVC decking manufacturers. Armadillo and Azek make strong decking materials but support some 30% less weight than that of their competitors.
Start by marking out a few possible locations to lay the foundations for your spa, somewhere that does not flood when it rains. You need space for the tub, the pump and equipment, and the surrounding platform.
One of the biggest concerns for spa owners is privacy. You do not want an audience of neighbors watching you. The easiest way to solve a curious neighbor is to put a gazebo over the tub that you can shield off with curtains. And most important of all, you want a view you can enjoy while you are relaxing.
You want to prevent people from slipping on the wet deck as they get in and out of the hot tub. Natural woods feel pleasant underfoot, but they can get slippery if they develop mold.
Composite and PVC decking is excellent for dissipating and draining heat and water. These materials are strong and easy to remove things like suntan lotions and oils with soapy water.
Hot tubs consume a lot of power through their pumps, heating, and lighting, meaning it is safer if the wiring runs as short a distance as possible to your home.
Some chemicals can come in heavy bags or tubs, so it’s useful to have a garden gate close to the spa for chemical deliveries. A hot tub needs constant maintenance, so you want to be near the main water supply to top it up with water.