How to Bid a Deck Building Job
Price per square foot, take off the framing like a pro, and stop forgetting the stairs — deck bids live and die in the details.
Bid deck construction per square foot, installed — material choice swings the price 3–5×, so the per-foot number has to be material-specific. The 2026 US ranges: pressure-treated wood $15–$30, composite $35–$60, hardwood $50–$75 per square foot installed. A 300 sq ft composite deck at $50/ft is a $15,000 job. Behind that number sits the real work: framing takeoffs, footing counts, railing and stair math, and the extras (demo, permits, lighting) that separate profitable bids from expensive lessons. Decks run 30–45% gross margins when every line is priced.
2026 deck building prices per square foot
Installed prices including framing, decking, standard railings, and labor. Stairs, demo, permits, and extras add on top.
| Material | Per sq ft | 300-sq-ft deck total |
|---|---|---|
| Pressure-treated wood | $15–$30 | $4,500–$9,000 |
| Cedar / redwood | $25–$40 | $7,500–$12,000 |
| Composite (Trex, TimberTech) | $35–$60 | $10,500–$18,000 |
| PVC decking | $40–$65 | $12,000–$19,500 |
| Hardwood (ipe, tigerwood) | $50–$75 | $15,000–$22,500 |
Material is the single biggest lever — but labor is the silent one. Composite decking with hidden fasteners installs 20–30% slower than face-screwed wood, and hardwood needs pre-drilling every hole. Your per-foot labor rate has to reflect the material you're actually installing, not a blended average from last year's wood decks.
The framing takeoff (where bids are won)
Most contractors price the pretty part — the decking — and guess the framing. Flip it: the framing is where the money hides. Work the structure first:
- Footings: count from your beam layout — beams every 8–10 ft, posts every 6–8 ft under each beam. A 16×20 deck typically needs 6–10 footings. Each footing = concrete ($5–$10 in bags or a share of a ready-mix load), a post base bracket, and digging labor. Below the frost line in northern zones: 30–48 inches deep.
- Posts and beams: 6×6 posts are the pro standard (4×4 is allowed in some jurisdictions but looks undersized on anything elevated). Double 2×10 or 2×12 beams, sized to your spans — check a span table, don't guess.
- Joists: 2×8 or 2×10 at 16 inches on center for wood; 12 inches on center for most composites (they're more flexible) and always 12 inches for diagonal patterns. Count = (deck width in inches ÷ spacing) + 1, plus rim joists and blocking.
- Hardware: joist hangers, hurricane ties, post bases, ledger bolts, and structural screws. Budget $200–$500 in connectors on a mid-size deck — the line item clients never question and contractors always forget.
- Ledger (if attached): flashing, lag bolts or structural screws, and the labor to open up siding properly. A failed ledger is a lawsuit; price the flashing detail like the liability it is.
Run the material counts through the deck & fence calculator as a sanity check — board feet, pickets, and concrete volumes are where mental math goes wrong on big decks.
Decking math: boards, waste, and fasteners
Decking quantity = deck area ÷ board coverage + 10% waste (15% for diagonal patterns or lots of cuts). A 300 sq ft deck with 5.5-inch boards needs roughly 690 linear feet of decking. Then price the fastening system honestly:
| Fastening | Material cost | Labor note |
|---|---|---|
| Face screws (wood) | $0.30–$0.50 / sq ft | Fastest; visible fasteners |
| Hidden clips (composite) | $1–$2 / sq ft | 20–30% slower install; clean look |
| Plug system (hardwood) | $1.50–$2.50 / sq ft | Pre-drill every hole; slowest |
The fastener line is small money with big labor implications. Bidding composite at wood-deck labor speed is the classic way to work a week for free — adjust your per-foot labor rate to the fastening system, not just the square footage.
Railings and stairs: price them separately
Railings and stairs never belong buried in the per-foot deck price — they vary too much job to job. Bid them as separate lines:
| Item | Installed price |
|---|---|
| Wood railing, per linear ft | $20–$50 |
| Composite railing, per linear ft | $50–$100 |
| Metal / cable railing, per linear ft | $75–$150 |
| Stairs, per step (wood) | $150–$300 |
| Stairs, per step (composite) | $250–$450 |
Code check: guardrails required at 30+ inches above grade, balusters max 4 inches apart, stair railings on both sides for wide stairs. Stringers max out around 6–7 steps per run — taller climbs need a landing, which is more framing, more decking, and more money. Measure the total rise during the site visit and count the steps before you bid, not after.
Site factors that move the number
- Demo of the old deck: $500–$2,000 for teardown and haul-off depending on size. Old footings and ledger removal are the hidden labor — bid demo as its own line.
- Height: second-story decks need taller posts, more bracing, scaffolding or pump jacks, and everything gets carried up. Add 15–25% over a ground-level bid.
- Access: no side-yard access means hand-carrying lumber and concrete. Price the labor or schedule a boom delivery.
- Soil and frost: rocky soil doubles footing labor; frost zones demand 30–48 inch depths. Carry a rock clause like you would on fence work.
- Permits and inspections: $150–$500 for the permit, plus two inspections (footings before pour, final). Failed inspections cost you the reinspection fee and the schedule slip — build to pass the first time.
Stack the upsells
- Lighting — post-cap and stair lights at $50–$150 per fixture installed. Clients love it, electricians are optional for low-voltage, and it photographs beautifully for your portfolio.
- Built-in seating — $500–$2,000 depending on design. Same crew, same materials, high perceived value.
- Under-deck drainage — $8–$15 per sq ft, turns the space below into dry storage or a patio. Easy sell on elevated decks.
- Staining/sealing — for wood decks, the finish is a natural follow-on. Our fence staining guide covers the per-foot math; deck staining prices the same way.
- Maintenance plan: reseal wood decks every 2–3 years. Book it now — the deck you built is the easiest sale you'll ever make.
Costly mistakes to avoid
- Forgetting the stairs. A 12-step composite staircase can be $3,000–$5,000 of a $15,000 job. Count steps on site, every time.
- Bidding composite at wood labor speed. Hidden fasteners and pre-drilling are 20–30% slower. Adjust the rate or donate the difference.
- Guessing footing counts. Draw the beam layout before you bid. Six footings vs ten is a full day of digging and a yard of concrete.
- No demo line. The old deck doesn't disappear by itself. Teardown, footing removal, and dump fees are real money.
- Ignoring the ledger detail. Improper flashing rots the house framing — the most expensive callback in decking. Price it like it matters, because it does.
- Verbal ballparks on big jobs. A $15,000 deck deserves an itemized quote from the quote builder, not a number from the driveway. Detailed quotes win against round numbers, and they protect you when the client “remembers it differently.”
Take off the framing in the deck & fence calculator, build the itemized bid in CalcBid, and send it before you leave the curb. Same-day quotes close at roughly double the rate of next-day ones.
Deck bidding questions, answered
Straight answers, no fluff. Then run your own numbers above.
How many deck boards do I need?
Deck area ÷ board coverage + 10% waste. For 5.5-inch-wide deck boards with 1/4-inch gaps, each linear foot of board covers about 0.48 sq ft — so a 300 sq ft deck needs roughly 625 linear feet of decking, plus waste = ~690 linear feet. At 16-foot boards, that's 44 boards. Composite boards vary by width, so check the manufacturer's coverage chart rather than guessing.
How many footings does a deck need?
Footing count follows your beam and joist spans, not the deck size alone. A common rule: beams every 8–10 feet, posts under each beam every 6–8 feet. A 16×20 deck typically needs 6–10 footings depending on the framing plan. In frost zones, each footing must go below the frost line (30–48 inches in northern states) — shallow footings heave and the deck follows them.
Should a deck be quoted per square foot or as a lump sum?
Do your internal math per square foot (materials and labor both scale that way), but present larger decks as an itemized lump sum: framing, decking, railings, stairs, permits. Clients compare lump sums; you manage margins per square foot. For small decks under 200 sq ft, per-square-foot pricing is fine because the number stays readable.
How long does it take to build a 300 sq ft deck?
A two-person crew builds a 300 sq ft pressure-treated deck in 3–5 working days: one day for footings and framing, one to two days for decking, one day for railings and stairs. Composite adds a day (hidden fasteners are slower than face screws). Permits and inspections add calendar time — 1–3 weeks in most jurisdictions — so start that clock at contract signing, not at mobilization.
Do I need a permit to build a deck?
Almost always, yes, for anything attached to the house or more than 30 inches off the ground. Permit fees run $150–$500 and inspections typically happen twice: once for footings (before you pour) and once at final. Build the permit cost and the inspection schedule into your bid — failed inspections and reinspection fees come out of your margin, not the client's.
Ledger board vs freestanding deck — which should I bid?
A ledger-attached deck is cheaper (fewer footings, less framing) but requires proper flashing and lag-bolt connections to the house — the #1 source of deck failures and lawsuits is a rotted or poorly attached ledger. Freestanding costs 10–15% more in materials and labor but eliminates the ledger risk entirely. On houses with questionable siding or no accessible rim joist, bid freestanding and explain why.
Run your own numbers
Reading is good. Math is better. Punch your job into the free calculator and turn it into a client-ready quote in minutes.