Composite Decking vs Pressure Treated Wood Decking: What I've Learned in 14 Years

Composite Decking vs Pressure Treated Wood Decking: What I've Learned in 14 Years

I've lost count of how many deck jobs I've done. The question homeowners ask most is composite decking vs pressure treated wood decking. It's a big decision because a deck is a big investment. Let me break it down based on real-world experience.

Cost: Upfront vs Long-Term

Pressure treated wood is the budget winner upfront. You're looking at $3 to $5 per square foot for materials. Composite runs $7 to $15 per square foot, depending on the brand and line. For a 400-square-foot deck, that's $1,200 to $2,000 for wood vs $2,800 to $6,000 for composite. But that's just the beginning.

Installation labor is similar for both if you're hiring a pro. But wood requires more skill to get it right without warping or splitting. I've seen plenty of DIYers save on labor but buy cheap lumber that twisted six months later. That's not a cost you save.

Over 25 years, composite can actually be cheaper. You'll restain or reseal a wood deck every 2 to 3 years. That's $300 to $600 per job if you DIY, $800 to $1,200 if you hire. Do that 10 times and you've spent $3,000 to $12,000. Composite needs only a wash every year or two. That adds up.

Maintenance and Upkeep

Pressure treated wood is a high-maintenance relationship. You have to clean it every spring, let it dry, then apply a stain or sealer. Miss a year and the wood starts to gray and crack. After a few years of skipping, the deck looks rough.

Composite is much easier. Just sweep and hose it down. If you get the capped composite (the good stuff like Trex Transcend or TimberTech AZEK), it resists mold and stains better. I've installed both, and homeowners who pick composite consistently tell me they spend way less time on upkeep. That's worth something.

But remember: composite can get hot in direct sun. Darker colors soak up heat. My advice: go with a lighter color if your deck gets afternoon sun.

Longevity and Durability

Pressure treated wood can last 15 to 20 years if you stay on top of maintenance. But in cold climates like Minnesota, freeze-thaw cycles take a toll. Water gets into the end grain, freezes, and creates checks. Eventually, the wood splinters and rots.

Composite lasts 25 to 30 years with minimal care. The capped stuff is practically waterproof. I've never seen a job where composite failed before 20 years. It's a solid long-term investment.

But there's a catch: composite can sag if the framing isn't beefy enough. And some composites expand and contract with temperature changes. I always leave a little gap between boards. That matters.

Appearance and Resale

Pressure treated wood weathers to a nice gray if you let it go natural. But if you want to keep it looking new, you'll be staining it often. Composite holds its color for the long haul. Fading is slight, and most brands up to 25 years.

When it comes to resale, composite often wins. Buyers see low-maintenance and high durability. I've been on appraisals where a composite deck added more value than wood. But it's not a huge premium unless the seller plays it up.

Which One Should You Choose?

Here's my straightforward take: If you're on a tight budget now and you're handy enough to maintain it, go with pressure treated wood. It'll serve you well for a decade or two.

But if you have the cash upfront and hate the idea of staining every few years, composite decking is the way to go. I've done both on my own deck, and I swapped to composite after my wood deck started cracking.

There's no wrong choice as long as you know what you're getting into. Just don't cheap out on the substructure—that's the part you can't see later.

Stay warm. Stay dry.
— Dean

##### Key Takeaway
Composite decking costs more initially but saves time and money over the long run. Pressure treated wood is upfront cheap but requires ongoing work. Pick based on your budget and tolerance for maintenance.

Installation Insights from the Field

Here's something most homeowners don't think about until it's too late: the substructure. Both composite and pressure treated wood decks rely on a solid frame. But composite is heavier, so I always use 12-inch on-center joist spacing for composite—not the standard 16 inches for wood. Failure to do so leads to bounce and sag. I've seen it happen with cheap composite brands.

Fasteners matter too. For pressure treated wood, use hot-dipped galvanized or stainless steel screws. Regular screws corrode fast because the treatment chemicals are copper-based. For composite, use the hidden fastener system recommended by the manufacturer. Trex Universal Clips, for example, work well. Don't use nails—they back out over time.

Another key point: expansion gaps. Composite expands more than wood with temperature changes. I leave a 3/16-inch gap between boards for composite, compared to 1/8 inch for wood. In the composite decking vs pressure treated wood decking debate, this is a detail that affects long-term appearance.

Lastly, end cuts. On pressure treated wood, seal any cut ends with a preservative to prevent rot. On composite, use color-matched caulk or a trim router to ease edges. Skipping these steps leads to premature failure.

Overall, the decision between composite decking vs pressure treated wood decking often comes down to how much you want to baby the deck. If you build properly, both can last. But composite gives you more room for error because it doesn't rot.