Composite vs. Wood Decks in New Brunswick: Which Lasts Longer?

If you're planning a new deck in Moncton, Dieppe, Riverview, or anywhere across New Brunswick, the first real decision isn't the size or the layout — it's the material. Composite or pressure-treated wood? The answer changes how much you spend up front, how many weekends you lose to maintenance, and how the deck looks ten winters from now.

As a Moncton deck builder with an InterNACHI Certified Deck Inspector on staff, we get asked this question almost every consultation. There's no single right answer — but there is a right answer for your home, your budget, and how you actually use your deck. Here's how the two materials really compare in NB conditions.

Why the New Brunswick climate matters

Deck materials don't fail randomly — they fail because of moisture, UV, and temperature swings. New Brunswick hands every deck a brutal test:

• Freeze-thaw cycles. Moncton typically logs 60+ freeze-thaw events per winter. Every cycle expands and contracts the boards, opens up checking in wood, and stresses fasteners.
• Heavy snow loads. Greater Moncton routinely sees 300+ cm of seasonal snowfall. Snow sitting on a deck for weeks means saturated boards, ice damming at the house ledger, and concentrated weight on joists.
• Atlantic humidity. Summer dew points in NB regularly stretch into the high teens. Untreated wood drinks moisture out of the air and lets it out slowly — which is exactly how rot starts.
• Salt air (coastal builds). If your home is in Shediac, Bouctouche, or anywhere within a few km of the coast, salt accelerates fastener corrosion. Galvanized screws that last 25 years inland might fail in 12 by the water.

Every comparison below is filtered through those four pressures. Generic "composite lasts longer" advice from a national deck blog isn't wrong — but it's not specific enough to make a smart decision for an NB home.

Pressure-treated wood: the affordable classic

Pressure-treated (PT) lumber is southern yellow pine or spruce that's been infused under pressure with copper-based preservatives. It's the default deck material across Atlantic Canada for one simple reason — it's affordable, locally stocked, and works.

What pressure-treated wood does well

• Lower upfront investment. The most budget-friendly decking option in Moncton — meaningfully less than composite for the same square footage.
• Natural feel. Real wood underfoot, real wood smell, real grain. Some homeowners simply won't trade that for plastic.
• Easy to repair. Damaged a board with a chainsaw blade or hot grill? Swap it quickly and inexpensively. Composite repairs are messier because boards weather and the new piece doesn't match.
• Stainable. You can change the colour anytime by stripping and restaining. Composite is whatever it shipped as, forever.

The real cost of wood is ongoing

The sticker shock isn't at install — it's over time. A pressure-treated deck in Moncton conditions typically needs:

• A full strip, brighten, and stain every 18–24 months — materials, supplies, and a weekend of work (or outsourced labour)
• Replacement of cupped or checked boards every several years
• Joist hanger and ledger inspection around year 10 — moisture often finds its way into the framing long before the surface looks bad

Over 20 years, that ongoing maintenance investment quietly closes most of the upfront gap with composite. It's the part of the equation most homeowners forget when comparing material options.

Composite decking: the long-term play

Composite is a manufactured board made from recycled wood fibre and polymers, capped on the top and sides with a hard, UV-stable plastic shell. The good news for NB homeowners: the technology has come a long way since the early 2000s. Modern capped composites don't fade like the first generation did, and the warranties have stretched to 25 years against fade and stain on premium lines.

What composite does well

• Near-zero maintenance. No staining, no sealing, no annual sanding. A garden hose and a soft brush is the full maintenance protocol.
• Doesn't splinter, rot, or warp. Critical for families with kids and bare feet. Critical for our climate.
• Hidden fasteners. Composite is built to use grooved-edge boards with hidden clip systems — no screw heads on the surface, cleaner barefoot finish.
• Resists ice damage. Doesn't absorb water, so freeze-thaw doesn't open up cracks the way it does in wood.
• 25-year warranties. Premium lines (TimberTech, Trex Transcend, Deckorators Voyage) carry fade and structural warranties that match or beat anything offered on wood.

The downsides of composite

• Higher upfront investment. Composite is meaningfully more expensive than pressure-treated lumber at install. Premium and PVC capstock lines are higher still.
• Heat retention. Dark composite boards can run noticeably warmer than wood on a sunny July afternoon. We design around this with lighter colours where shade is limited.
• Cosmetic limits. The deck looks like what you ordered, forever. You can't restain it to refresh the look in year 10.
• Frame still matters. The composite boards last 25+ years. The pressure-treated frame underneath still has to be built right, with proper joist tape, flashing, and drainage.

Side-by-side comparison for NB conditions

Beyond the upfront vs. long-term investment trade-off, the honest comparison for a Moncton-area homeowner looks like this:

• Upfront investment: Wood is budget-friendly · Composite is mid-to-premium tier
• Expected lifespan in NB: Wood 15–20 years · Composite 25–30 years
• Ongoing maintenance: Wood requires regular staining and sealing · Composite is essentially zero-maintenance
• Homeowner time per year: Wood eats weekends · Composite needs a hose and a soft brush
• Resale impact: Wood is neutral · Composite typically lifts perceived home value

So which should you actually choose?

Here's the framework we walk every client through:

Choose pressure-treated wood if:

• Budget is the primary driver
• You're planning to sell the home within 6–8 years
• You genuinely enjoy deck maintenance (some people do)
• You want flexibility to change the colour or stain later
• The deck is small — the lifecycle math gets thinner on tiny decks

Choose composite if:

• You plan to stay in the home 8+ years
• You have kids, dogs, or you walk barefoot on the deck
• You'd rather spend summer Saturdays on the deck than sanding it
• You're in a coastal area (Shediac, Bouctouche, Saint John waterfront)
• Resale value matters and you want a finished, premium look

What stays the same either way

Whichever surface material you choose, the parts of the deck that actually fail in NB conditions are usually invisible:

• The ledger board attachment to the house (this is the single most common cause of catastrophic deck collapse — and it's almost always behind siding)
• Joist hangers and the corrosion rating of the fasteners
• Flashing where the deck meets the house
• Footings and how they handle frost heave

This is where having an InterNACHI Certified Deck Inspector on the build crew matters more than the surface material. We see beautiful, expensive composite decks installed over rotten ledgers all the time. The boards on top look amazing for 20 years. The ledger fails in 8.

Frequently asked questions