Cost data reviewed August 2026. Sources listed at the foot of this page.
Decking material is the decision that sets your budget
Everything else about a deck — the framing, the footings, the labor — is broadly similar whatever you walk on. The surface material is what moves the number, and it moves it a long way.
| Material | Installed per sq ft | Upkeep | Realistic life |
|---|---|---|---|
| Pressure-treated pine | $25 – $50 | Clean and reseal every 2–3 years | 15 – 20 years |
| Cedar | $30 – $47 | Reseal annually to hold color | 15 – 25 years |
| Redwood | $28 – $54 | Reseal annually | 20 – 30 years |
| Composite (Trex-class) | $40 – $80 | Wash occasionally | 25 – 30 years |
| PVC (AZEK-class) | $50 – $80 | Wash occasionally | 30 – 50 years |
| Aluminum | $100 – $125 | Essentially none | 40+ years |
The Cost vs. Value report puts a national wood deck addition at $18,263 and a composite one at $25,096 — a composite premium of about 37 percent, which lines up well with the per-square-foot figures above.
Does composite pay for itself?
Not usually in cash, but often in effort. Take a 16 × 12 ft deck, 192 square feet. Pressure-treated at the midpoint is roughly $7,200; composite is about $11,500 — a $4,300 premium. Sealing a deck that size costs $200 to $400 in materials and a weekend of work every two to three years. Over 25 years that is perhaps $3,000 and eight or nine weekends.
So the money roughly washes out over the full life, and the honest way to frame the choice is: do you want to spend $4,300 now to never sand and seal a deck again? For plenty of people that is an easy yes. It is just not a financial argument.
Height changes more than you would think
A ground-level deck sits on short posts, needs no guardrail in most codes below 30 inches, and often needs no stairs. Raise it and you add taller posts, larger beams, mandatory guardrails, a longer stair run, and — critically — work at height, which is slower. The calculator applies a modest uplift for raised and elevated decks; treat it as an indication, since published per-square-foot data does not isolate this variable.
Where deck budgets go wrong
- Footings. In a cold climate, footings must reach below the frost line — four feet in parts of the upper Midwest and Northeast. That is real digging and real concrete.
- Railings. A composite railing system can run $60 to $100 per linear foot. On a deck with 40 feet of exposed edge, that is a line item, not a detail.
- Stairs. Stairs cost far more per square foot than deck surface. Each tread is cut, each stringer is laid out, and the whole assembly needs its own footing.
- Permits and setbacks. Most jurisdictions require a permit for an attached deck, and some have setback rules that will change your design before you start.
- Ledger flashing. The connection to the house is the most common point of catastrophic failure in deck construction. It is not the place to economize.
Common questions
How much does a 12x16 deck cost?
A 12 × 16 ft deck is 192 square feet. In pressure-treated pine that is roughly $4,800 to $9,600 installed; in composite, about $7,700 to $15,400. The spread within each material is driven by height, railing choice, stairs and site conditions more than by the decking itself.
Is Trex cheaper than wood?
No — Trex-class composite runs $40 to $80 per square foot installed against $25 to $50 for pressure-treated pine. Composite wins on maintenance over a 25-year life, not on purchase price.
Can I build a deck on an existing frame?
Often, and it saves a great deal of money since framing and footings are a large share of the job. But have the existing structure inspected first — particularly the ledger connection to the house and the condition of the joists. Putting a 30-year deck surface on a frame with 5 years left in it is a false economy.
Do I need a permit for a deck?
In most US jurisdictions, yes, for anything attached to the house or above a certain height — commonly 30 inches. Requirements vary widely by municipality. Building without one can complicate a future sale, since it will surface in inspection.