is composite decking slippery

Is Composite Decking Slippery When Wet?

In Lawn & Garden, Tips by Jamie

It’s really hard to enjoy your new deck when you’re constantly slipping around or worried about someone breaking a hip. While composite is low-maintenance, it also comes with a reputation for being really slippery. Is this reputation deserved?

Composite decking will be more slippery when wet than when dry, but whether this is a cause for concern depends on the particular product line. While most composite falls below the slip resistance benchmark for safety (and can even be outright dangerous), some composites exceed these requirements. Weather, cleanliness, and installation can also make composite decking more slippery.

Why is Composite Decking Slippery?

Composite decking may be more slippery when it has:

  • Smooth texture. Composites’ grip comes from its texture. After getting initial complaints about how plastic the original composites looked, manufacturers started designing material with a wood-like grain texture. Not only does this look more attractive, but it also provides better grip. The deeper and more defined the embossing is, and the rougher the finish, the more grip the product has. Budget composites tend to be smoother than more expensive, higher quality composites.
  • All decking materials are more slippery when wet, and regardless of material, you should build the deck with gaps between planks for drainage and tilt the deck so that water runs off the slope instead of accumulating. Shaded areas will stay wetter for longer as it doesn’t get enough sun to dry off quickly.
  • Dirt, debris, mould, and fungus growth. If you don’t clean your deck regularly, dirt and leaves will accumulate on your deck and cause mould and fungus growth. Even if your composite has a deep embossing, too much debris and fungus will steal away the tread. Debris can also plug up the gaps between board so that water pools on the deck instead of draining. To avoid this, pressure-wash or scrub your deck twice-a-year.
  • Ice, frost, and snow. As with all decking materials, if it’s covered in ice, it’s going to be slippery. Like debris and fungus, ice and snow can plug up the tread, making it more slippery. Ice can also damage the composite material. To keep your deck safe and in top shape, regularly remove ice and snow with a non-metal shovel.
  • Older composite materials. Composite manufacturing and design has come a long way in recent years, but if you have an older deck, it will absorb moisture faster than newer products. More moisture means more mould and moss, which means it’ll be slipperier. Older composite may also have more shallow embossing, if it has any at all.
  • Vinyl materials. Composite products made from vinyl are more slippery than composite made with PVC.
  • Planks installed longitudinally along high-traffic areas. Just like with real lumber, grip depends on the direction the grain patterns run. Going with the grain will be more slippery than going against the grain. So if your planks were installed so that you frequently walk along the length rather than the width, then the boards will be more slippery.

Is Composite Decking Slippery in the Winter?

Yes, composite decking can be slippery in the winter, especially when ice, frost, and snow accumulate. If the composite product in question is slippery when wet, then it’s going to be slippery in the winter. Choose composite decking that’s deeply textured, pressure-wash or scrub the decking clean before winter arrives, and shovel snow and ice off your deck using a non-metal shovel.

Can You Buy Non-Slip Composite Decking?

You can buy composite decking that comes with grooves on one side instead of the wood-grain pattern. This looks less aesthetic, but it can make a big difference in how much traction it provides. Consider using the grooved sides in heavily trafficked areas or places like stairs. Always order a sample and try it out for yourself before committing!


What Composite Decking Has the Best Grip?

Before buying composite decking, always run your hand over the sample and pick a product that has a rough texture. The wood-like texture gives the material its grip.

Slip resistance is tested with the grain and against the grain and in both dry and wet conditions. The higher the rating, the more slip resistance it has, and 0.5 is the benchmark for safety. Depending on your circumstances, a result below 0.5 may be perfectly serviceable, but for older people, people with disabilities, and in places with challenging weather, don’t go below this mark. (Chances are, if you’re reading this article, you need a higher rating.)

According to the Canadian Construction Materials Centre (CCMC), a third-party organization that tests building materials to check that they’re up to standard, the top brands for grip include:

Zuri by Royal Building Products

A PVC composite material, Zuri premium decking tops the list in terms of slip resistance at 0.82 dry and 0.89 wet). It also looks fantastic, with non-repeating grain patterns, and a 25-year guarantee that the colour won’t fade.

Wolf Serenity Decking

 Wolf Serenity also scores pretty high at 0.74 dry and 0.75 wet. This is a great pick if you’re in a rainy or coastal region as it has high resistance against moisture, mold, and mildew. And, of course, they have a 50 year fade warranty.

Paramount by Fiberon

Paramount is actually a PVC and not a composite (no wood involved), but has the same wood-like look. It also has pretty high slip resistance at 0.80 dry and 0.75 wet. Paramount is approved for all Wildland Urban Interface zones (WUI) and passes the additional requirements of San Diego County. This is a great pick if you’re in a wildfire prone area.

Voyage by Deckorators

Deckorators use Mineral-Based Composite (MBC) rather than wood-based composite, which gives it several benefits, including a superior strength-to-weight ratio, very little thermal expansion or contraction, and better traction at 0.73 dry and 0.66 wet. For best traction, go with their Voyage line.

NeoTimber

Based in the UK, NeoTimber makes double-sided decking with one side featuring grain patterns and the other side featuring grooves. Their Advanced line has a rating of 0.82 dry and 0.36 wet for the wood grain side, while the grooved side has a rating of 0.80 dry and 0.40 wet.

Decks by E3 has put together a complete list of CCMC slip-resistance ratings.

Wondering if composite decking gets as scorching hot as they say? Check out our guide for 6 Ways to Keep Composite Decks Cool Enough To Walk On.


How Do I Make Composite Decking Less Slippery?

It’s easy to say that you need to try samples ahead of time, but what if you’ve already discovered just how slippery your brand new deck can be? Before scrapping your new (expensive) deck, try these fixes first.

1. Pressure-Wash the Deck Twice a Year

One of the major causes of slippery composite is because of debris buildup. Not only does it fill up the tread, but mould and fungus can grow on it. Dirt and debris can also block the space between boards, keeping water from draining away as well as it should. By pressure-washing or scrubbing between the boards and in the tread, you’ll open up blocked drainage and get the treads back.

2. Install Non-Slip Treads

If only some key areas are slippery, like stairs, then installing non-slip treads will help and will still look attractive. There are some very attractive options out there that will fit your deck’s aesthetic, like Handi-Treads’ aluminum products. You may also be able to buy specific treads from your deck’s manufacturer or replace the steps with composites made with grooves instead of wood-grain pattern.

Before installing non-slip treads, check whether installing other vendors’ treads voids your warranty. Depending on how slippery your deck is, it may be worth it.

Avoid grit tape as it won’t stick well to composite decking and you’ll have to replace it within a year. It’s also not very attractive.

3. Apply Anti-Slip/Grit Paint

If your entire deck is slippery, your most cost-effective option is to apply anti-slip or grit paint. Grit paint is an abrasive coating that you can paint over other materials. Painting can be tricky, though, as not all grit paints will adhere to composite decking, so experiment with different bases before buying the paint. Most grit paints are opaque, so it’ll change your deck colour. Slip Doctors’ Floor Grip is designed to work on composite without changing the look of the composite.

You will need to reapply grit paint every 5 years or so, depending on your outdoor conditions, and you can’t use a metal snow shovel or you’ll chip the paint. (Metal shovels can damage bare composite as well.)

Check with your deck’s warranty before applying paint! Applying paint may shorten or void the warranty.

4. Apply Anti-Slip Mats

If you don’t want to void your warranty with grit paint, then you can put heavy-duty, rubber anti-slip mats in the high-trafficked areas. This isn’t the most attractive option, but it’s an option.


Composite Decking FAQs

Is Trex Composite Decking Slippery?

Many people report that Trex composite decking can be extremely slippery, even when clean and dry, while a few others report never having problems. If you go with Trex, go with their premium Transcend line, which scores just below the benchmark for slip resistance (but scores higher than many other composite product lines). Always get a sample before committing.

What is More Slippery – Composite or Wood Decking?

Wood decking usually rates higher than composite in terms of grip, although this can change drastically depending on the wood species, the composite product, maintenance, and weather. Sealing wood, for example, reduces traction. Different wood species have different levels of traction, as do different composite products (even varying widely from the same brand). When possible, get your hands on samples so that you can feel the texture for yourself. If it’s smooth, it’ll be slippery. If it’s rough, then it’ll grip better.

What’s The Difference Between PVC And Composite Decking?

PVC and composite decking look very similar and they both feature a “cap”, an added layer of protection that makes them more durable. PVC is made entirely from plastic, while composite decking is made from blending wood fibres with plastic. PVC products or composite made with PVC are generally more slip and heat-resistant than composite.