Since I first wrote about the problems with composite decking in 2018 there have been a lot of comments and questions especially recently asking me to update the info and if any of these issues were still true. So, I have fully updated the information with references to new products on the market and changes here in mid-2024. I only hope it helps people make an informed decision.
There are a lot of options for decking today. It’s not like the old days where you had to simply choose between different species of wood. Today, you have all of the wood options of yesterday, but now there are scores of different composite decking options.
If you been a reader of my blog for any amount of time, you’re probably thinking “Oh now, here he goes again bemoaning another modern product.” Well, I want to tell you that that is not the case. I don’t have problems with new products, only subpar ones.
Sadly, most composite decking falls into that category. It has been improving slowly over the years with the introduction of capped decking, and technologies like CoolDeck among other upgrades, but still, the reports from consumers and contractors are not promising. Take a look at some of the websites where homeowners have posted their reviews, and you’ll read 1 and 2 star reviews all day long.
7 Problems With Composite Decking
There are a multitude of problems with composite decking that show up all too often to be just a stray issue for a hard to please homeowner. The accounts of issues are repeated with a frightening regularity and sameness throughout the threads of complaints.
Many homeowners acknowledge the issues, but still prefer the composite decking to traditional wood decks, usually due to the maintenance required for wood decks. Below are some of the issues that crop up most often.
1. Composite Decking is Slippery
In the last few years Trex and Deckorators have release “slip-resistant” versions of their composite decking, and while these are better than the older composite decks they are still far more slippery than a wood deck.
When you put water on top of plastic it is always slippery since it cannot absorb the water like a wood deck can. It’s a just a fact of life that composite decks are still going to be more slippery than wood decks.
There are aftermarket non-slip coatings you can apply to your composite deck. I can’t speak to the effectiveness of these coatings since I haven’t used them myself, but I know they are out there if you are wanting to experiment and find a potential solution to your slippery composite deck.
2. Hotter Than Wood
Composite deck manufacturers have been working on this issue for decades with very little improvement other than marketing spins. Today you’ll find CoolDeck technology from MoistureShield and Transcend Lineage by Trex which “is engineered with heat-mitigating technology to give you our coolest decking yet.*” I had to search for where that asterisk was referenced and here was the answer from their page:
“*Although Trex Transcend Lineage is designed to be cooler than most other composite decking products of a similar color, on a hot sunny day, it will get hot. On hot days, care should be taken to avoid extended contact between exposed skin and the deck surface, especially with young children and those with special needs.”
If you live in a northern climate this might not be an issue for you, but anywhere in the southern US and you likely will suffer from this issue. It’s not just the issue of being hot on bare feet but also the heat that will be radiating from this deck while you sit on it. Summer is hot enough without a deck radiating a ton of heat back at you.
If you still insist on composite decking then choosing white or light grey colors will keep the deck surface cooler, not as cool as wood but slightly lower than the surface of the sun.
3. Tighter Joist Spacing
If you are planning to simply replace your existing wood decking with composite decking you need to be sure that the supporting structure of your deck is sufficient. For wood decks covered with 2×6 or 2×8 boards 24” O.C. joists are not uncommon. Most wood decks using 5/4” decking will require 16” O.C. joists. Composite decking can be different though.
Dan Gileo of Decks & Docks has been working in the decking industry for over 25 years and his recommendation is a minimum of 16” O.C. joist spacing for straight installations, whereas 12” O.C. would be required for diagonal installations to avoid sagging.
Composite decking varies by manufacturer and even though it may be fine for several years at the wider spacing, many installations I have come across begin to sag even with 16” O.C. spacing after the 10-12 year mark. So I would recommend sticking with the 12” O.C. to be safe.
Also, many composite decking materials require 12″ or even 9″ on center stair stringers spacing to support composite stair treads.
The point is make sure you account for the added time and costs of reframing the support structure if you are changing from wood to composite.
4. Mold & Staining
Especially prevalent on older and uncapped composited decking, mold shows up quickly and is more difficult to eradicate than you’d expect. The mold seems to grow heavily not just on the surface, but inside the rough texture of uncapped decking. It seems to come on strong and takes constant effort to keep the decking clear of it, especially for a self-proclaimed “no maintenance” product.
Even with the recent technology improvements mold and algae still shows up quicker than I would expect. Staining is another problem with composite decking. Depending on the landscaping even things as simple as the tannins in fall leaves or berries can permanently stain these composite deck boards so be sure you don’t have issues in your location.
5. Color Fading
Everybody knows color fades in the sun, but composite decking companies seem to be oblivious to what their products are really capable of. Some composite decking has faded so quickly in just a couple of seasons that replacements boards stand out like a sore thumb. Just like the mold, this issue is unpredictable and hard to understand which decking will have problems and which will not.
Trex currently offers a 50-year warranty on their top line decking, but it’s hard to imagine the deck will be anywhere near the same color it was when originally installed. And unlike wood decks where colors can change over the years as you stain them the options for changing the colors on a composite deck are extremely limited.
6. Warping & Shrinking
It’s not wood, so it shouldn’t be expanding and moving the same, right? Right! It actually moves more AND more unexpectedly than wood decks. Some composite decking won’t move a bit and others have been found to shrink, swell, warp, twist, bow, and any other word you want to use in amounts unheard of, even with wood.
Again, it seems completely random when this happens, but it happens often enough that you should know about it. The best explanation is that plastics have greater movement than wood and as materials heat up they expand more. So, with a composite deck that is largely made of plastics and gets hotter than wood decks the movement can be extreme.
7. Sagging Boards
Even if you use the proper spacing composite deck boards are notorious for sagging. Especially the lower end products. The top of the line products have done an excellent job at preventing this today, but there is still enough sagging in the best boards that it makes me uncomfortable using them.
I notice this issue showing up after a decade or more of use, and when it does it usually makes the deck unusable. On my own house I have a composite deck that is 21-years old at this point and the sagging is extraordinary to the point we can’t really use the deck until I have the chance to replace it. Check out the video below to see how springy these boards can really get!
What To Do?
For now, I’d say the best way to avoid problems with composite decking are to avoid it altogether and stick with wood. You may be one of the lucky ones who installs composite decking and gets away with it, or you may end up constantly on the phone trying to persuade them into the honoring their warranty, which is extremely hard to do.
Sure, wood has issues of its own and requires staining occasionally (here’s a great tutorial on staining wood decks) but it’s nothing that will take me by surprise. And if it needs a replacement piece, it’s as easy as swinging by the local lumber yard rather than trying to track down a model that has been discontinued five years ago from a supplier halfway across the country. As for me, I’m sticking with wood. How about you?
Composite decking has come a long way since it first came out, but it’s not there yet. Someday, the industry may be able to create a consistent long-lasting product that lives up to the claims and avoid the problems with composite decking currently, but right now, they can’t seem to make it work. When they can make a product that is consistently better than wood, then I’ll be in line for it, but until then I’m sticking with a reliable option like wood.
If you’re looking for a reliable wood option that has little to no maintenance and can easily last longer than composite decking I would encourage you to check out Accoya. It is not the same as traditional treated lumber and is perfect for a deck even in the toughest elements.
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I love old houses, working with my hands, and teaching others the excitment of doing it yourself! Everything is teachable if you only give it the chance.
We looked at a wide range of plastic/composite decking, and one issue that was a problem for us was damage. If you use your deck, sooner of later you will scuff it, scrape it, or drop something sharp on it. The advice from the deck companies? Use a hair dryer or heat gun on it to soften it up and try to ‘weld’ it back together.. Ridiculous. With wood, I can sand and reapply the finish and be done. To top all that off, there’s cost. The stuff is more expensive than a high-quality wood! We wound up going with Cumaru, which requires little maintenance (coat of oil every other year) and actually was more cost effective per linear foot.
Love Cumaru! Great wood for decks!
We had a good local carpenter put a new porch/deck on our seasonal house in Nova Scotia. I asked about a synthetic surface and he told me it would get very hot, as that entry faces southeast and has sun on it most of the day. We went with pressure treated southern yellow pine which is probably not ideal in terms of old house purity but it certainly works, and does not get too hot on a 90 degree day.
A friend 1/4 mile up the road insisted on a synthetic surface on his new deck. And has found it too hot on days with a lot of sun.
Hi Noel,
That’s a common complaint we hear from people that have gone with synthetic/composite decking- way too hot for anyone’s feet, especially down here where we are located in Florida.
Thanks so much for reading and commenting!
-Alyssa at The Craftsman Blog
We just bought some, haven’t installed yet. I am in Texas and it is 87 here today. I touched the boards and it viscerally hot. We were going to use it for deck around above ground pool. Should we take it back???
It’s up to you, but composite always gets crazy hot to the touch. Imagine what it will be like in the afternoon in that 100+ Texas summer. Wood is always a better option for temp control.
We’re also in Texas and are in the design phase of a deck around our above ground pool. While we enjoy the covered wood deck on our house, we do not want the same level of upkeep around the pool. We will likely have a sun-sail type shade covering most of the decking, but heat is definitely an issue. Has anyone installed Cali Bamboo Composite Decking or have experience with other types than Trex? I also read about Millboard based in the U.K., but no U.S. distributors yet. Thanks!
I live in the Rocky Mnt’s where the weather gets extreme. We’re getting ready to replace our wood wrap around decking with Compostie or Vinyl wrap (contractor suggested vinyl). But with NO knowledge of either I’m reaching out for information. I’ve been reading about http://fortressdeck.com. Is anyone familiar with this one or have suggestions? We are retiring and really don’t want the hassle of maintaining a wooden deck anymore. TIA
We used the mid-level Fiberon (Flagstaff) with the lifetime guarantee. The underpinnings of the deck were no more than 16″ apart and it was installed properly with space between the board ends. In less than 6 months, the boards warped. I contacted Fiberon and they wanted details. I sent them (pictures, specs, etc) and they have not replied. Good thing I purchased with AMEX. I am going to make them replace it or refund me for the cost of the product as it was not cheap! #hellhathnofury
I agree that there is much less appeal these days with composites especially here with bay area decking. Although the composite decks are less maintenance initially the problems are abundant sand customer service from the largest suppliers is quite poor. I am a deck builder of 20+ years and i have certainly seen the shift back towards wood even the quality of wood is also being challenged
Peter, what type of wood do you recommend for an area in the northeast with a lot of humidity/rain/termites?
Take a look at Accoya
What about the wet Northwest, i.e. Portland, OR. Which kind of wood would you recommend here?
Hi Cindi,
The climate is different than here in Florida, but still damp like it is here. Our best recommendation would be to use this directory to find a licensed preservationist in your area who has in-person expertise with that specific climate. thecraftsmanblog.com/directory
Best of luck to you!
-Alyssa at The Craftsman Blog
We have a trex deck that we are adding a small piece to at a cabin. We have the boards cut and sitting flat on the deck waiting for us to return and install and screw down. Do you think the boards will warp in the hot sun 95 to 100 degrees if they aren’t installed in the next 3 weeks?
I don’t know about warping (though I’ve read a lot of comments about warping etc) but we moved into a house this week with Tex Transcend. The outside temp is 85 degrees and in the sun the deck get’s so hot we won’t even go near it in the heat. I burned the crap out of my feet in about 20 seconds. I’m terrified my dogs will get out there during the day and get hurt.
It’s amazing the temperature difference between a wood deck and composite!
We had a new dock built with azak last September. It is so bad with dirt/ mold stains that won’t even come off with a pressure washers. Any suggestions? Second guessing not going with wood….
We moved into a house that has 3 decks made out of composite. We have the worst trouble with the one that gets direct morning sun. Tons of warping and now uneven to walk on. Gets extremely hot. Is there a solution to warped boards?
There is a “newer” composite decking that does not have the challenges of the older generations of composites – it is less hot than other composites to walk on, less slippery, stronger, lighter and more stable. It has a 25 year warranty that includes removal and replacement. It is DecKorators Vault and Frontier decking. This deck material has been around for over 10 years and is growing in acceptance. It has no wood chips inside it to mold or mildew or rot. It does not have the expansion problems of PVC. It is so strong, you can swing a sledge hammer at it several times, HARD AS YOU CAN, and it will NOT break! AND, it doesn’t get brittle or weaker in freezing weather, and can be in ground contact or submerged in snow or water. This stuff is amazing!
100% recycled plastic deck anyone?! Hi, I am over in the UK and have just taken delivery of my deck. I was put off composite after some research… my understanding being that composite means your deck is a mix of wood “flour” and plastic… sounds like a mixture of MDF and plastic so of course the rot and is going to get in eventually. The answer for me was to go 100% recycled plastic. This was by a company called GovaDeck and whilst the price was eye-watering when compared to pressure treated softwood I’m hoping for zero maintenance once installed. Grey seemed to be the only available colour that looked decent, so it’s quite modern looking.
I can keep you posted maybe after a cold season, I would also be interested to know if anyone else has any thoughts on/experience of using this material. Thanks
Kyle, now that we are in the summer months what is your feedback as temps change in regards to warping and are you able to use the deck without shoes? Love the idea but with my Colorado sun I am concerned about mostly about how hot it gets.
Hi Danielle,
We’ve had a couple people comment/write us before and say that they had bad experiences with burns on their feet on composite decking 🙁 we wish this wasn’t the case. We would much rather have our theory/opinion proved wrong than hear that people are getting hurt.
-Alyssa at The Craftsman Blog
We have verenda decking in back yard. Worse choice we could have made when it comes to decking. It literally burned the bottom of my granddaughhters feet. I called Home Depot and they told me to call Veranda. Called Veranda and there response was to wear shoes. .
Feel this material should be banned from all stores. Please if anyone knows how to correct this problem please let me know.
Hi Kathy,
Oh my goodness, we are SO sorry to hear that. Stories like this make us so sad. There are a lot of reasons we believe original materials are better, and stories like this make us wish that they didn’t prove our point because people are getting hurt.
Best of luck to you in the future and thanks for reading our blog and joining the discussion.
-Alyssa at The Craftsman Blog
Our composite “expensive” deck was worst choice ever! 30 years of wood, what were we thinking? If you have kids or dogs or sun do not get it! It is so hot and radiates heat in the 70s we do not go on it. This summer I will be spending hundreds of dollars on shade items and outdoor carpeting to try to get use of our very huge deck!
I had composite wood on my dock for over 15 years now. Love it. Yes it would get hot in the summer on bear feet but just splashed water on it. Little heavy but loved it.
Our17 year-old trex deck has changed color yet remains solid on 12″ on-center joists without warping or maintainance issues. I call BS on detractors comments about this superlative product. When all else fails, read the instructions.
Replaced wood with composite about 10 years ago. We got mold spots after a year or so. Fortunately we were able to eradicate the black mold spots using Olympic deck cleaner combined with scrubbing and pressure washing. Not a material recommended by Trex. It seems like the issue has gotten better in recent years, in that I haven’t had to clean or scrub as much. Originally we had to do this twice a year, once in the spring and again in the fall. While there has been some color fading, I consider it moderate. I have a question for anyone with some information. Is it advisable to use a waterproofing material like Thompson’s. We just cleaned it this year and I thought that might help make future cleaning easier.
I was going to replace my old wood front porch with this stuff. I thought, “No painting!” “No maintenance!”.I guess this is not the answer…..Thanks for saving me a ton of money.
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It is so tempting to use composite….and vinyl siding…and vinyl windows…and spray foam. The amount of plastic/petroleum products that are on/in houses these days is quite astounding.
A few years back I lived in a condo building that had some composite decking as part of a walkway. Only a few years after installation there was extreme warping to the point that it was a tripping hazard.
Wow, thank you for posting this!
I’ve built a couple of redwood decks at our houses and was seriously thinking of using Trex for the next house. I too was sold on the “No/low maintenance” aspect of using it. Now I see that’s really not the case at all.
Looks like I’ll be sticking with Redwood and stain every couple of years!
I just installed composite (Trex Transcend) on by deck as part of a major rehab (new wood on about 1/2 the framing plus getting up to code). I agree that the cheap and middle tier stuff can be garbage, but I think you should look again at some of the higher end products offered these days. They probably don’t save any money (damn it was like 3x wood price), but it is convenient not having to shovel spring snow off the deck every other day (snow in the spring melts then piles again then melts, causing anaerobic rot on wood, even pressure treated).
We’ll see how well it holds up fading-wise. At least I have good shade 3/4 of the day.
I think I’m in the unpopular group on this topic! ? We installed Trex composite decking on our 1900 country Victorian about 12 years ago. My husband and I spent hours debating whether to use wood or composite. Our winters are harsh and our house is sited in a damp’ish location. After four big dogs and two rough kids, the decking still looks great and is wearing well. The color has faded a bit and we do get the occasional moss growth. We pressure wash it about every three years. Meanwhile, my neighbor, who installed a covered wood deck is sanding and coating about every four years. Overall I’m very pleased with the product performance and would definitely choose it again.
Hi Laurie,
I’m so glad to hear it’s working well for you! Thank you for sharing your experience!
Best,
Alyssa at The Craftsman Blog
You are definitely in the minority but I’m glad you have had a good experience with your Trex! Thanks for sharing Laurie!