What pressure-treated decking actually looks like over 10 years
PT is the budget deck material, but every "PT vs composite" cost comparison ignores what the wood actually LOOKS like at year 5 and year 10. This time-lapse is honest about the maintenance curve so you can decide if the lower upfront cost is the right trade-off.
- Year 0 — wait 30-60 days to dry, then stain
- Year 1 — annual pressure wash
- Year 2 — light sand + re-stain (semi-transparent)
- Year 4 — stain refresh
- Year 6-8 — heavy sand + solid-color stain or full re-stain
- Year 10-12 — board-by-board replacement of worst
- Climate variation (PT ages faster in wet vs dry climates)
- Full physical cracking + cupping geometry
- UV intensity (south-facing decks age 2× faster)
- Specific stain brand color variation
Cost out pressure-treated for your deck
PT lumber for a 12×16 deck: ~$1,400 material upfront, plus ~$1,200-1,800 in cumulative maintenance (stain × 4-5 refreshes, sander rentals, board replacement). Composite for the same deck: ~$3,800-4,800 material upfront, ~$150 cumulative maintenance (occasional wash). At year 12-15, PT total often EQUALS composite — except composite still looks new and PT looks tired.
Pressure-treated FAQ
How long does pressure-treated decking last?
Structurally: 25-40 years if the lumber stays attached and dry-cycle conditions persist (most PT deck failures aren't the lumber — they're hardware corrosion or footing heave). Cosmetically: 1-2 years before grey-out begins; 5-10 years before splintering + cupping become noticeable; ~15-20 years before it's visually past pleasant without major refresh. With biennial stain refresh you can keep PT looking 'maintained' for 20+ years.
When should I stain a new pressure-treated deck?
Wait 30-60 days from delivery for the wood to dry to ~18% moisture content (the level stain can penetrate). The water-test: sprinkle water on the board — if it beads, the wood is still too wet. If it absorbs, you can stain. KDAT (kiln-dried after treatment) lumber can be stained immediately but costs ~25-40% more. Skip the wait and the stain peels off in sheets the next summer.
Does pressure-treated decking need to be stained?
Technically no — PT is rot-resistant by chemical treatment. Practically yes if you want it to look maintained. Untreated PT goes grey within 2 years and develops surface checking + splinters within 5. Annual washing + biennial semi-transparent stain keeps the surface usable indefinitely. Skip maintenance entirely and budget for full board replacement at year 12-15.
What's the difference between PT and composite for decking?
PT pros: half the material cost (~$2.40-2.80/sf vs $5.00-7.00/sf for composite), the look that 'feels like real wood,' standard tools + fasteners. PT cons: requires annual maintenance, splinters, fades to grey, surface texture roughens, can warp / cup / crack. Composite pros: zero maintenance, stable color, smooth surface, 25+ year warranty. Composite cons: 2-2.5× upfront cost, gets hot in dark colors, less "wood-like" feel. Most buyers in 2026 pick composite if they can absorb the cost; PT remains the budget option.
Are pressure-treated boards safe to walk on barefoot?
Modern PT (post-2003) uses ACQ / MCA / CA-C copper-based treatments — much safer than the old CCA arsenic-based PT. Walking barefoot on cured PT is fine. Avoid: (1) freshly delivered PT before it dries (residual surface chemicals), (2) PT that's developed splinters (mechanical injury risk, not chemical). Don't burn PT scraps — copper-based smoke is toxic. PT is fine for vegetable garden borders if it's modern non-CCA stock.
What's the cheapest way to refresh an aged PT deck?
Pressure wash (rental: $40-60/day) + chemical brightener (~$25 for an 8×10 deck) + semi-transparent stain (~$120 for 1 gallon, covers 200-250 sf). Total: ~$200-400 + a weekend of labor. Compared to: full board replacement (~$2,000-4,000 for the same deck) or full composite resurface (~$3,500-6,000). The refresh option works as long as boards are structurally sound and the cupping isn't extreme.
Can I sand a PT deck instead of pressure washing?
Yes — sanding is actually better than pressure washing for badly weathered boards. A floor sander with 60-grit will cut through the silvered surface layer and expose fresh wood underneath in 1-2 passes. Then 100-grit for finish. Pressure washing alone can't remove the deep checks or restore smooth texture. Cost: ~$70-90/day for floor sander rental + ~$30 for sandpaper. Two-person crew can sand an 8×10 deck in 4-6 hours.
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