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.
Founder & Editor-in-Chief
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.
My trex deck installation minimum gapping between pieces has closed up over time and filled in with pine needles and other debris. This is causing drainage problems and staining of the pieces is becoming very difficult to clean. What can be done to open up the gaps between runs? Considering Can running a skill saw with an 1/8” blade between each piece it to open up a gap for drainage?
If the decking is capped then ripping it with a skill saw will reveal the uncapped portion which will cause more performance issues. Not sure if there is a solution other than cleaning out the needles consistently or removing the birds and reinstalling with bigger gaps.
First we used a skill saw to create a gap between boards because some areas had none. Now about once a month I take a putty knife and push whatever debris either out of the gap or push it through the gap depending on the size of the debris. No pooling of water anymore. Much less mold and decomposing of the Trex material. Next up is painting it to seal the Trex better who approves of a product sold by Home Depot. Found it on their website.
Could agree more with this article. We installed composite decking 12 years ago and will be tearing it up next spring. Boards are spongy and bounce and some have broken completely. The company we bought from declared bankruptcy but from what I have read I am staying clear. My friends pressure treated deck is going on 19 years with no issues. He treats it every other year and hasn’t had to replace a board. Going to build with pressure treated and use the new hidden fasteners. No need to screw the boards in from the top anymore. A 1/3 of the cost and it can’t be any worse than what we have. I have read that the warranties that come with composite are useless. Companies will use any excuse to avoid paying. Check out the complaints regarding TREX via the better business bureau.
I have a Fiberon Deck that is failing miserably. The last two years it started cupping and splitting and the last two months has become a severe trip hazard. We spent over 15,000.00 on materials. Fiberon is now saying that it is because of a lack of ventilation. Their reps were out here prior to even laying the product to inspect the infrastructure as I wanted a diagonal deck. My deck is 8 years old. I am going to start a media blitz about all of this garbage. Fiberon was here 4 times during our installation. I just found out yesterday that their composite deck is a wood byproduct that is wrapped in vinyl. Did anyone else know this.
That is the core of the Fiberon business all though they have a PVC product now and you should have been educated by your installer. We carry a number of samples to explain this very issue with every client. Capped composite can do the things you are saying especially Fiberon because their capped product is not wrapped on the bottom and they cut the groove into the board after they cap it. This defeats the purpose of the PVC coating as it just gets the core wet from the bottom and the groove. What you are experiencing is the result of the core containing wood which will act as wood does regardless of what it is mixed with. I am sorry to hear about your experience and wish you were better taken care of during your initial deck shopping.
Yankee Lady and Foothill Family posted almost identical reviews (“Trex has a life of its own, and behave better when horizontal”) less than 12 hours apart. Someone is poisoning the well here.
I have been in business for a very long time and I will be the last one to say that the customer is always right and in most cases they are not but having said that. I am a firm believer in standing behind your product and services. I built my house in 2002 and its consider a high end build in my area of the country and the builder I used was considered one of the best. They used Trex decking on both deck top and bottom. The lower deck looks like a skate park. It has warped really bad. I have reached out to Trex and they won’t cover the problem because they say it’s the joist underneath that’s causing the problem along with the boards being to close together. When they constructed this house it was done right including the deck. I know how a deck is to be installed including Trex and it was done correctly. Just like pressure treated wood decking you still have to pressure wash the boards to keep them clean. If the claim is maintenance free I dont know where. My advice would be to stick to traditional wood. This is obviously a product that is inferior and until they can perfect the product save yourself some time and money and use wood for your decks.
Or use Millboard! You don’t get any of these problems you are all moaning about, but..there is a catch…..they don’t supply into the US yet.
What is millboard??
Composite done right will last as it should.
We had a Fiberon deck installed two years ago. It has been nothing but a problem since then. The boards had a “dusty, dirty” look to them and nothing would clean them up. We contacted the manufacturer and got no help at all other than to tell us that we should buy a cleaner they recommended. We did that and it did nothing. Even our dog’s footprints will not clean up. We are so disappointed and would never recommend this decking or this company to anyone. We spent a lot of money to have a “trouble free” deck and in the past two years we have spent more time trying to get this one clean than in all of the past 42 years we have been in this house with wood decks.
I totally agree! I had a new deck built this summer with Fiberon composite deck boards and am having the same issues/problems with keeping them clean. My deck is only 1 month old and looks filthy all the time. I reached out to Fiberon and they told me how to clean it…ridiculous that it should take that much work to clean a deck that is supposed to be literally maintenance free! I’ve purchased other composite decking that is a breeze to keep clean. I am regretting my decision to choose Fiberon.
Would you mind sharing which Fiberon deck line you chose? I am currently considering Fiberon Symmetry.
I am having the same problem with my new Fiberon deck. Cannot get the boards clean. Contacted the company who told me how to follow a ridiculous cleaning method…I told them it shouldn’t be that hard to keep deck boards clean. I’ve tried everything, including getting on my hands and knees and washing each board individually. Pressure washing doesn’t work, nor does scrubbing with a soft-bristled brush. Really regret my decision to use Fiberon composite decking.
Inferior product.
My trex deck is warping badly this season. It’s about twenty years old so I don’t know if I should have it ripped out and new deck put in
That Trex product was their original raw composite board. It’s probably swollen, stained and nearly twice as thick as it was when installed. You could pressure wash and stain if you are on a budget otherwise it is time to pull it out and start over.
Hello all who have posted here!
I hear you frustrations and concerns and feel for you. If you could encourage someone in America to consider importing Millboard decking I can promise you you would not get the issues your talking about. Without sounding like I’m selling Millboard is made from resin rather than plastic and didn’t react to temperatures like plastic does. We have been importing to Australia and the Middle East for about 6/7 years now and though Millboard does get hotter than timber it’s not as hot as plastic, but the amazing thing about it is that it doesn’t move like plastic does, is expand Inthe heat and become soft or shrink in the cold and become brittle. It contains no protein based materials like wood flour/dust, rice husk, bamboo fibre to feed the growth of miss/algee or black mould and is totally non porous. This makes it genuinely low maintenance and in fact the more rain you get on it the better as it helps to wash it down. I would encourage you to look up
http://www.millboard.co.uk
I seriously feel sorry for you folks facing these issues as there is a solution.
Kind Regards
Russell
We had our deck replaced last July, and chose Trex Select. Since that time, the fascia board around the perimeter of the deck appears to have warped and the mitred corners have separated. The fascia board used along the sides of the stairway also seemed to twist.
Our contractor has replaced the fascia boards along the side of the stairway about a week ago, and it already appears to be “rippling” in between the areas where fasteners are affixed. He plans on replacing the fascia board around the deck perimeter, but I am concerned that we will have a recurring problem. I am considering just having them replace the fascia with wood and keep the Trex on the deck flooring and steps. It seems as if Trex has a life of its own, and behave better when horizontal but does peculiar things when used in a vertical application. Any ideas?
Composite fascia boards are too think to not react like this in the summer. We stay away from composite fascia and use smart trim instead painted to match deck or house or something like that. You are fighting a losing battle I would yank it off and have it replaced with something else.
After a lot of thought, we replaced the old deck on our house last July. We decided on Trex after researching and noting that the previous problems were seemingly resolved. The deck flooring and steps were Trex Select, and the sides of the deck and stairway were Trex fascia board.
Since then, the fascia board on the sides has bowed creating a large gap at the 45 degree mitered corners. The sun-exposed side of the stairway had bowed. Our contractor came out and has replaced the board on the side of the stairs, but within less than two weeks, it is buckling up in between the areas with fasteners! The contractor has suggested that more fasteners will fix the problem, but I sense that Trex has a life of its own and seems to behave when it is horizontal vs with vertical or oblique uses. Has this been noted? I am about ready to have them remove all the fascia board and just replace it with wood.
My husband has installed our co posited decking and after 2 weeks with all the rain we have had it’s fading but we were told this that it would fade by 15% in 2. Months ,scratches easily , you can only clean it with soapy warm water , as I tried cleaning a stain with white spirits and some of the decking has gone a lighter colour , wouldn’t buy it again
Like Laurie, our experience with Trex has been good. I’m not sure what level of Trex we have – likely Select – but we’ve had it for about 10 years now. No problem with warping or fading. The deck was poorly built, without enough space between slats to drain water, so water collects on it and it gets dirty and mossy, but power-washing cleans it well.
I am very confused now . I thought by going to composite , my problems would be over . My wife and I are also retired and trying to get away from the work involved with a deck We have already torn our old deck apart . It is a 20 x 24 deck to be done . Is there a wood that can be used that does not require a lot of staining and maintenance .
Our deck get lots of sun for the better part of the morning . We live in Canada ,so are winter are harsh and our summer here are always filled with sunlight . So confused . HELP .
Carlo! All I can say – we’re in the same situation. We were going to install composing decking but after all of these reviews, I’m absolutely lost.
Me too! I have contractors coming out tomorrow and the next day to give me estimates. I had hoped to go Trex becuase my current deck which is wood , teh boards are cracking and splitting and I get tired of staining every year. But now reading all these posts, I am having second thoughts. How much have you all been quoted to build your Trex deck?
I have to replace my beautiful tile deck.that was destroyed by a hail storm. I live in Colorado with extreme temperature swings. I have been looking at pavers from timbertech. Does any one have any experience with them?
Scott,
You the MAN!!!
I have been telling my customers the same thing for years. Glad to see a kindred soul.
Lee Smoak
Craftsman Direct
craftsmandirect.com
Hey, how do you think about the material which is100% plastic lumber? Is it better than composite lumber? Or any experience you can share to me? Thank you very much!
I’ve been installing Trex since 2007, I’d heard of issues but never experienced any. Went to see a couple of examples and clearly the installation was a DIY error which I helped remedy. This last August and early September I installed a trex deck for some dear friends. Then I went on vacation and came back to finish it. In mid October it rained and then November it froze. The ends of the trex began to swell up at the butt joints,, never seen that before. Yesterday I examined the deck and the butt joints have swollen more. I’ve contacted both Trex and Home Depot. They are looking for fine line reasons to NOT honor their product. Trex says that because I used unapproved fasteners that they caused excessive moisture build up which caused the swelling. I’ve seen trex under 2 feet of snow and used as a dock surface over water. This is a defective produce and no one wants to be responsible. Home Depot is saying that because they didn’t install it that they are not responsible. I believe that the Trex rep is reading from a script designed to disparage my installation and find any reason possible to NOT honor their warranty. I’ve searched the internet and can’t find another example of expanding ends when there is plenty of space between the boards at the butt joint. I also have pics of a DIY job where the butt joints were installed tight with no gap and the boards did not swell up. There is moss growing between the boards in many places and the boards did not swell.. If anyone else is having this issue please contact me..
Thanks, Bill
Hey Bill, I installed a Trex deck 8 yrs ago and it seems like it is falling apart. It’s spongy and mushy and looks like it is going to fall to pieces within a year. I paid $30,000 to have it installed. I do not know where to go to try and get my money back. All I can think of is take a picture of it and put it on the internet to warn people not to buy this product and stick to real wood decks!!
Hi Bill,
I am a master carpenter, 32 years and still going! I love to design/build decks in the summer months. I am over 500 decks built in my career! In the past few years I have been installing Trex decking and rails. I am currently a Trexpro gold. I have over 50 deck warranties filed with Trex.
I receive very few calls for service, most are from installation.
You made a statement that your butt joints were swelling. Trex recommends no butt joints on decking. If you must create a butt joint, (which you never have to.) you need to install a double joist or block at the location. I always picture frame full length boards. It just takes a little planning, and a whole lot of blocking! Trex gets a bad name from poor installations. They have come a long way in 10 years! Go Trex!
Moisture Shield has 30 years in the field with zero structural failures. They even offer transferability of Structural Warranty. This includes installing on the ground, in the ground or underwater. Could be time for a change.
We are going to build a deck on the North side of our house. Our contractor says that we can use Trex decking for the floor but that we should use redwood with sicken for the railings. He said that in his experience the Trex railings have warped. The north side of our house does not get really intense sun but I am concerned about mold because the deck is shaded for a long portion of the year. What is your experience with railings warping and mold in these conditions?
yes yes little jill they will warp and my baby did doo nuffin
Woodbridge, VA, 26 October 2018.
In the last month I have been working with a contractor on plans for a small porch to be built over my townhouse front stoop, using Trex Transcend, Island Mist or Vintage Lantern, for ease of maintenance. Are there still longevity/performance issues with the product?
Building new home with decks, in Portland OR. What kind of wood do you recommend?
Hello, I live in the Pacific Northwest (Idaho). My house is situated in a damp location next to a creek. Winters here are a bit harsh as well. We put rhino composite decking on about twelve years ago and haven’t regretted that decision. While it has faded a bit and had a little moss from time to time, a quick power washing cleans it up nicely. It looks great and there are no splinters or sanding/refinishing.
Need to replace a small 13 x 7 ft deck over dirt in a kind of atrium patio that is completely enclosed on all four sides, gets hardly any moving air and is very hot 10 months out of the year (Houston, TX) but little direct sun on the surface. Installed a wooden deck seven years ago and it is completely soggy and rotten (also due to Harvey hurricane).
One contractor suggested Trex, one suggested brick looking 12×12 pavers. Any comments on what would be best.
Hi Tina!
We live in an area that gets a ton of moisture too (Orlando, FL)
Our best and safest recommendation is to use our directory to find a licensed preservationist in your area who can provide an accurate recommendation upon seeing it in person. https://thecraftsmanblog.com/directory/
Good luck!
-Alyssa at The Craftsman Blog
Use those bricks that they use on driveways. It allows the water to seep through when it rains into the ground table. They come in different colors and if one should crack, it can easily be replaced. No upkeep!
Thanks for this brilliant information. I have 55 degree days in summer and minus in the winter. The foot burning problems with composite decking sounds exactly what’s happening with the artificial turf that’s being laid in the city gardens. So-called low maintenance, but can’t be walked on on a sunny day. Will go with real timber – I’d rather oil once a year than use harsh mold-busting chemicals that damage the environment and garden. Mould is a significant health risk as well. Once it’s there, you never can get rid of it.