Pressure-treated lumber is the cheapest deck material on the DFW market, and it’s also the most demanding once it’s installed. Texas summers brutalize untreated PT — the combination of 100°F+ days, brief but heavy thunderstorms, and winter freeze-thaw cycles (rare, but real) checks, twists, and greys the surface faster than in milder climates. This post is the realistic month-by-month schedule that keeps a PT deck looking right for the full 15–20 year structural life.
The first six months: wait, then seal
PT lumber arrives at your site wet from the treatment plant. The boards are saturated with the copper-based preservative solution (typically MCA or CA-C in 2026 — the post-CCA generation of treatments) and need to dry to a moisture content below 15% before stain or sealer will properly absorb.
In DFW, that drying period is roughly 4–6 months in dry years, 2–4 months in wet years. Putting stain on PT that’s still above 15% moisture content gives you a finish that peels and flakes within a year, because the moisture migrates out from the core and breaks the surface bond. Do nothing to the deck during this period except clean off leaves and debris.
At the 4–6 month mark, do the splash test: sprinkle a few drops of water on the boards. If they bead up, the surface is still too wet for sealer. If they absorb within 30 seconds, you’re ready.
First treatment: late summer to early fall
Best window in DFW is mid-September to early November. The summer heat has broken, daytime temperatures are 70–85°F (sealer cure range), and the boards have had a full Texas summer to dry. Skip the late-spring window even if it’s tempting — spring sealer applications get baked off by the first summer’s UV before the protection takes hold.
Process:
- Clean the deck.A garden-hose rinse and a soft- bristle deck brush with a deck cleaner (oxalic-acid based, like Defy or Olympic). Don’t use a pressure washer above 1500 PSI — PT is softer than cedar and high pressure raises the grain. Let dry 48–72 hours.
- Apply a penetrating oil-based water-repellent stain. DFW favourites: TWP 1500 series, Cabot Australian Timber Oil, Defy Extreme. Two thin coats brushed in are better than one thick coat rolled on. Budget: $80–$140 in product for a 200– 400 sq ft deck.
- Avoid film-forming products. Polyurethane and paint-based deck coatings fail catastrophically in Texas heat. They blister and peel within two summers. Stick to penetrating stains.
Total time: one weekend. Total cost DIY: $120–$200 including cleaner, stain, and brushes. Contracted: $550–$900.
Years 2 through 5: spring and fall rhythm
After the first treatment, settle into a twice-a-year rhythm:
March or early April (spring clean)
Hose-and-brush clean to remove winter debris, pollen, and any algae or mildew that took hold during the wet winter months. No stain needed in spring. Inspect for any boards that have cupped, cracked through, or pulled away from fasteners. Drive any lifted screws back down or replace them with stainless-steel deck screws if the original galvanized hardware is showing rust.
October or November (fall reseal)
Every 18 months in DFW, the stain protection has burned off enough that you need a fresh coat. That means alternating fall treatments and skip-falls: reseal in fall year 2, skip fall year 3, reseal fall year 4, skip fall year 5, etc. If you stretch the schedule beyond 24 months between treatments, you’ll see UV greying in the surface boards that no future sealer can fully reverse.
Annualized cost across the maintenance cycle: $180–$320 DIY, $550–$900 contracted.
Years 5 through 15: structural inspection
Once a year, walk the deck with a flathead screwdriver and probe the following points:
- The ledger board where the deck attaches to the house. Probe the wood behind the ledger flashing if you can access it. Soft wood = water intrusion behind the flashing = call a contractor immediately. This is the failure point that drops decks off houses.
- The post baseswhere the deck meets the concrete piers. PT is rated for ground contact but the joint where wood meets concrete is where moisture sits longest. Soft post bases mean the post needs replacement — not a huge job but get on it before the year goes by.
- Joist hangers and fasteners. The galvanized hangers most contractors used pre-2010 corrode within 15 years in DFW humidity. Look for rust streaks or visible pitting. Replace with stainless or hot-dip galvanized hangers when needed.
- Stairs and stringers. Stair stringers carry a lot of weight on the cuts where the treads attach. End grain on those cuts is where rot starts. Probe with the screwdriver.
Budget $200–$500 every 3–5 years for replacement hardware, the occasional rotted board, and one or two post-base repairs across the deck’s life.
What to skip
A few things sold to DFW homeowners that aren’t worth the money:
- Annual sealer applications.Anything more frequent than every 18 months is wasted money — the boards can’t absorb fresh sealer faster than that, and a thick buildup of unabsorbed product peels.
- Pressure-washing every spring.The grain damage from repeated pressure-washing accelerates the surface checking you’re trying to prevent. Hose and brush is enough most springs.
- Painting or solid-stain coverage.Builds a film that blisters in Texas heat. If you want a coloured finish on PT, use a semi-transparent stain — never a solid stain or paint.
The honest bottom line
A PT deck in DFW that follows this schedule costs $1,400–$2,400 DIY across the first five years (above the install cost), or $3,200–$5,200 contracted. That’s the maintenance gap between PT and capped composite over the same window. If you’ll do the work yourself, PT is genuinely the cheapest deck you can build in DFW. If you won’t, the maintenance gap eventually closes against composite, and the composite deck looks better the whole time.
Run your specific build through the calculator and toggle between materials to see the install-price gap on your particular footprint.