DeckMath
New Jersey · 20×12 (240 sqft) · 2026-Q1 retail

20×12 Deck Cost in New Jersey

A 20×12 (240 sqft) deck in New Jersey costs $14,640-$23,520 in mid-tier composite with the state's 1.22× labor multiplier (Northeast). A 12×20 deck (240 sqft) is a long, narrow deck — common for ranch-style homes with a long back wall. New Jersey labor 1.22× national. Coastal areas have additional environmental review.

240 sqft1.22× laborFrost 36snow climate64 lf perimeter
Area
240 sqft
20×12
PT pine (budget)
$7,440-11,760
$31-49/sqft installed
Mid composite
$14,640-23,520
$61-98/sqft installed
Luxury PVC
$22,080-32,160
$92-134/sqft installed

5 finish tiers — 20×12 in New Jersey

National $/sqft × New Jersey's 1.22× labor multiplier × 240 sqft = total installed cost. Materials + labor + standard railing included.

Tier
$/sqft
Total low
Total high
Budget · Pressure-treated
PT pine
$31-$49
$7,440
$11,760
Mid · Cedar / premium PT
Cedar
$43-$67
$10,320
$16,080
Premium · Mid composite
Trex Transcend, Fiberon Sanctuary
$61-$98
$14,640
$23,520
Luxury · Premium composite
TimberTech AZEK, Trex Signature
$92-$134
$22,080
$32,160
Exotic · Tropical hardwood
IPE, Cumaru
$110-$171
$26,400
$41,040

Excludes permit ($240-$592 typical in New Jersey), demolition (if replacing), and exceptional framing for 36″ frost depth. NJ permits $250-450. Coastal towns add Pinelands or CAFRA review.

20×12 framing notes for New Jersey

Joist size
2×10 @ 16″ OC
Span 20 ft requires 2×10 SYP or PT pine for IRC R507.6 compliance. Check Joist Span Calculator for exact spans by species + spacing.
Beam configuration
2-3 beams
A 20×12 deck typically needs 2-3 beams depending on whether you can drop joists onto the beam (1) or hang them flush (2+).
Post count
6 posts
6×6 PT posts at 6-post layout typical. Footings extend below 36″ frost line.
Footings
6 × 36″ deep
Sonotube 10-12″ diameter at 36″ depth per IRC R403.1.4. Concrete budget: ~$329.
Decking
396 lf
240 sqft × 1.65 lf/sqft = 396 lf of deck boards at 16″ joist OC. Add 5-7% waste for cuts.
Railing
64 lf perimeter
64 lf of railing (~$36/lf mid composite, ~$22/lf wood). Stairs need 2 extra handrails (1 each side).

New Jersey considerations

Labor multiplier
1.22×
Northeast region labor pricing on all installed costs.
Frost depth
36″
Footings extend below frost line per IRC R403.1.4. Standard footing depth.
Climate
snow
Freeze-thaw cycles favor PVC over composite where budget allows.
Top metros
Newark · Jersey City · Paterson
Major metros drive installer availability + pricing pressure.
Permit fee
$240-$592
NJ permits $250-450. Coastal towns add Pinelands or CAFRA review.
Region
Northeast
Northeast regional pricing applied. Multiply national $/sqft by 1.22× for New Jersey installed cost.

Get a precise quote for your 20×12 deck in New Jersey

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FAQ — 20×12 deck in New Jersey

How much does a 20×12 deck cost in New Jersey?

In New Jersey, a 20×12 (240 sqft) deck costs $7,440-$11,760 in pressure-treated, $14,640-$23,520 in mid-range composite (Trex Transcend / Fiberon Sanctuary), and $22,080-$32,160 in luxury composite/PVC (TimberTech AZEK / Trex Signature). Numbers reflect New Jersey's 1.22× labor multiplier on 2026-Q1 retail.

What's the cheapest way to build a 20×12 deck in New Jersey?

Cheapest = ground-level pressure-treated pine with no railings (where exempt under 30″ height) — ~$5,856-$8,784 in New Jersey. Add stairs + railings + above-grade framing and the build goes to ~$8,198-$11,712. DIY saves 30-50% on labor but requires permit + inspection coordination yourself.

How long does it take to build a 20×12 deck in New Jersey?

Permit timeline in New Jersey: 2-6 weeks depending on jurisdiction. Construction time for a 20×12: pro crew = 5-8 days for framing + boards + railings + stairs. DIY = 3-5 weekends for experienced DIYer. Allow extra time for permit approval + inspections.

What framing do I need for a 20×12 deck in New Jersey?

IRC R507-compliant framing for a 20×12 deck typically uses 2×8 joists at 16″ OC for spans up to 12 ft, 2×10 joists for spans 12-16 ft. New Jersey's frost depth is 36″ — footings must extend below that per IRC R403.1.4. Sonotube 10-12″ diameter at 36″ depth is typical. Verify with your local building department.

Is composite worth it for a 20×12 deck in New Jersey?

Over 25 years in New Jersey: PT pine = ~$8,784 install + ~$18,300 maintenance (stain every 2-3 yr) = $27,084 total. Mid composite = ~$16,982 install + $0 maintenance = $16,982 total. Composite wins by 59-81% over 25-yr lifecycle PLUS better resale value in New Jersey's market.

Compare New Jersey brand pricing for a 20×12

Same 20×12 in other states