Wood deck maintenance over 10 years, the real cost

Hand painting wooden decking with a brush during a yearly stain refresh — Photo via Pexels

Every homeowner who picks pressure-treated pine thinks they\'ll stain it every two years. Most don\'t. After year three the "I\'ll do it this spring" promise gets broken. The deck greys. Boards cup. The homeowner ends up either living with an ugly deck or paying a pro $2 per sqft to restore it.

Here\'s what PT deck maintenance actually costs over 10 years if you do it right (and what it costs if you let it go). Numbers are for a 320 sqft deck, but they scale linearly.

Year 1: the critical first stain

PT pine from the lumber yard has too much moisture to accept stain immediately. You wait 6 to 12 weeks after install (longer in humid climates) then apply the first coat of penetrating stain.

What to buy: Ready Seal, Cabot Australian Timber Oil, or Penofin. All semi-transparent oil-based penetrating stains. Avoid film-forming (Behr DeckOver style) products because they peel catastrophically when they fail.

Cost: 3 gallons for 320 sqft at $55 per gallon = $165. Plus oxygen bleach cleaner ($15) and brushes/rollers ($20). Roughly $200.

Time: 8 hours. One day to clean and dry, one day to apply. I do this Memorial Day weekend every year.

Year 2: pressure wash only

Year 2 the stain still looks good. Just wash off winter grime with a garden hose and a long-handled deck brush. If you own or rent a pressure washer (be careful with PT, it\'ll fur the wood fibers), use it on low pressure.

Cost: $15 for oxygenated cleaner or $45 to rent a pressure washer for 4 hours. $20-$50.

Time: 2-3 hours.

Year 3: second stain coat

Year 3 the first stain coat has thinned out and uneven areas are showing. Time for a refresher.

Clean first with oxygenated deck cleaner (not chlorine bleach, it kills the wood). Let it dry 48 hours. Apply a fresh coat of the same stain brand you used in year 1.

Cost: 2 gallons of stain ($110) plus cleaner ($15) = $125.

Time: 6 hours.

Year 4: first cupping appears

Some boards start showing cup (the edges lift higher than the center). Usually 1 to 3 boards on a 320 sqft deck, mostly in full-sun sections. Nothing to fix yet; cupped boards don\'t structurally fail for years.

Cost: zero. Just notice it.

Year 5: third stain, first board replacements

Another stain cycle. Also, the cupped boards from year 4 are starting to crack. I replace 2 to 4 boards around year 5 on a PT deck.

Board replacement: $22 per board (5/4 x 6 x 12 ft PT from Home Depot) plus screws plus 45 minutes per board if your fasteners are face-screws, or 90 minutes if you\'re using hidden clips.

Cost: 3 boards at $85 all-in = $255. Plus stain ($125). Total $380.

Time: 10 hours.

Year 6: inspection year

Check every connection. Joist hangers, railing post bolts, stair stringers. Tighten any that have loosened. Check the ledger flashing for any water staining.

Cost: zero unless you find an issue. Budget $50 to $200 for small repairs.

Time: 2 hours.

Year 7: fourth stain, more boards

Stain again. 4 to 6 boards need replacing now. This is where PT starts to feel like work.

Cost: 5 boards at $85 = $425. Plus stain $125. $550.

Time: 12 hours.

Year 8: the surprise failure

Around year 8 on a humid-climate PT deck you start seeing rot at the joist-to-post connections. The moisture traps between the PT joist and the Simpson Strong-Tie joist hanger. The joist itself stays okay; the joint rots.

Fix: replace the joist hanger. Sometimes replace the end of the joist too. This is $75 per joist repair in materials plus 2 hours per joist.

I\'ve had 2 joist hanger replacements on my first PT deck at year 8 and 9.

Cost: 2 joist repairs at $150 = $300.

Time: 4 hours.

Year 9: fifth stain

Stain. By now the texture is inconsistent because you\'ve replaced boards that weathered differently than the originals. Stain evens it out but never quite makes it look new.

Cost: $125.

Time: 6 hours.

Year 10: reckoning

10 years in on a PT deck you either re-skin the top (replace all deck boards, keep the framing) or you start planning full replacement in the next 3 to 5 years.

Re-skin: 35 new boards at $22 = $770, plus 40 hours labor (DIY) or $800 to $1,200 if you pay someone. $1,900 to $2,000 total.

I\'ve re-skinned my first deck at year 11. Boards looked 100 percent new after. Framing underneath was still solid because the Z-flashing on the ledger had kept water out.

Cost: around $1,900 for a DIY re-skin. Plan for it.

Ten-year total (maintained well)

Year 1: $200 (stain)
Year 2: $40 (wash)
Year 3: $125 (stain)
Year 4: $0
Year 5: $380 (stain + boards)
Year 6: $50 (repairs)
Year 7: $550 (stain + boards)
Year 8: $300 (joist repair)
Year 9: $125 (stain)
Year 10: $1,900 (re-skin)

Total: $3,670 over 10 years. On a $9,600 build that\'s 38 percent of the install cost in maintenance. Steep.

Ten-year total (neglected)

If you skip stains after year 3, don\'t do the year 6 inspection, and let boards fail without replacement, the deck is dead by year 8. Not because PT can\'t last, but because water and UV destroy unprotected wood.

Neglected deck at year 8: needs full replacement. $9,600 again. Total lifetime cost: $9,600 install + $9,600 rebuild at year 8 = $19,200. Two decks for the price of one-and-a-half.

Don\'t be that homeowner.

The composite alternative

Trex Enhance installed at $12,800 on the same footprint. 10-year maintenance: about $80 in cleaner, total. That\'s a $3,590 maintenance delta vs PT, which means composite\'s upfront $3,200 premium pays back in year 10 if you were going to maintain the PT anyway.

If you weren\'t going to maintain the PT, composite was the right call from day one.

What to do if your deck is already there

Clean it. Oxygen bleach, not chlorine. Let it dry 48 hours. Apply stain. Even a 7-year-old neglected PT deck can be restored with two stain coats and some board replacements. Call a contractor for an estimate if you don\'t want to DIY; $2 per sqft is the going rate for a "deck restoration" service that includes cleaning, sanding, and re-stain.

Plan it into the budget

When you use the DeckCalc estimator, the number it spits out is install cost. Add roughly 4 percent per year for PT maintenance, or 0.5 percent per year for composite, to get the honest long-term cost. The calculator doesn\'t do that automatically yet (it\'s on the roadmap). For now, mental math.