Deck Building Cost in King of Prussia, PA (2026)

Updated October 2026 · King of Prussia, PA · index 1.08

Average cost in King of Prussia$12,200$8,400 – $15,900$28 – $53 per sq ft
Priced for: A 300 sq ft deck, pressure-treated woodSplit: 47% labor · 53% materials
Price your own job ↓

How much does it cost to build a deck in King of Prussia? For a 300 sq ft deck with pressure-treated wood, homeowners in King of Prussia, PA pay about $12,200 on average, and most quotes land between $8,400 and $15,900 — $28 to $53 per sq ft. The price covers plans and the permit, footings, a framed and flashed structure, the deck boards, railing, one set of stairs, fascia and cleanup.

The deck building price in King of Prussia runs 8% above the U.S. average: construction labor in the King of Prussia area runs 15% above the national mean, materials 3% below. The same job averages $11,300 nationally and about $11,300 at the Pennsylvania statewide index.

Deck Building cost calculator for King of Prussia

100 to 800 sq ft

Decking material
The job
Estimated cost in King of Prussia$12,100$8,400 – $15,900$40 per sq ft · 47% laborGet exact quotes from local pros

Are you a deck builder? Price jobs like this in 60 seconds

Deck building price in King of Prussia by decking material

What a 300 sq ft deck costs in King of Prussia with each decking material, installed:

OptionAverage · range
Pressure-treated woodtreated pine or fir boards, stained and sealed$41 per sq ft$12,200$8,400 – $15,900
Capped compositehidden fasteners and a picture-frame border$49 per sq ft$14,600$10,400 – $18,800

The least expensive option in King of Prussia is pressure-treated wood, at about $12,200; capped composite averages $14,600, 1.2 times as much.

Cost to build a deck in King of Prussia by size

With pressure-treated wood, priced for King of Prussia, PA:

SizeAverage · range
A 200 sq ft deck$44 per sq ft$8,750$5,950 – $11,500
A 300 sq ft deck$41 per sq ft$12,200$8,400 – $15,900
A 400 sq ft deck$39 per sq ft$15,600$10,800 – $20,300

Some costs stay the same whatever the size — plans, permit and layout, one set of stairs (4 steps), final inspection and cleanup — so a bigger job costs less per unit: $39 per sq ft for a 400 sq ft deck against $44 for a 200 sq ft deck.

What a deck building in King of Prussia includes

Line by line, the $12,200 average for a 300 sq ft deck breaks down like this: 47% labor, 53% materials and equipment.

LineLow – high
Plans, permit and layout$400 – $1,200
Ground prep, fabric and gravel$240 – $600
Footings below the frost line$450 – $890
Flashed ledger on the house$270 – $520
6x6 posts$300 – $600
Beams$270 – $520
Joist framing with hangers$1,550 – $2,600
Deck boards$1,450 – $2,150
One set of stairs (4 steps)$560 – $1,100
Railing$2,050 – $3,550
Fascia and skirting$390 – $930
Final inspection and cleanup$160 – $400
Stain and seal, two coats$360 – $830

Each line is the price book's U.S. rate for that step, scaled by 0.74 to the installed price published sources give for the whole job (see how these prices are built), times King of Prussia's index of 1.08; permit fees are not scaled.

Get free quotes from King of Prussia contractors

Describe your project once and JobFlex sends it to a local deck builder who prices it for your home — free, no account needed.

Get free quotes

What affects deck building prices in King of Prussia

Labor and materials in King of Prussia

Construction wages in the King of Prussia metro run 11% above the U.S. mean (BLS, May 2025), and specialty-contractor pay in the city's county moves that up by 4%, to 15% above the national mean. Materials in the area's ZIP codes price 3% below the national average. Together they give King of Prussia a construction cost index of 1.08.

Where King of Prussia sits in Pennsylvania

King of Prussia ties for the most expensive of the 9 Pennsylvania cities in our index, against a statewide index of 1.00. Erie is the least expensive at 0.94.

Against the rest of the country

Of the 306 U.S. cities in JobFlex's index, King of Prussia ranks 96th from the most expensive. The job that averages $12,200 here averages $11,300 at the national rate.

Frost depth in Pennsylvania

Deck footings go below the frost line, or they heave by the second spring. The typical code frost depth in Pennsylvania is about 36 in. — deep holes, more concrete and more digging time than in the South. Your building department sets the exact figure.

The deck code in Pennsylvania

Decks here are built to the Pennsylvania Uniform Construction Code — residential (2021 IRC with Pennsylvania amendments). Guards are required at 36 in. where the deck is more than 30 in. up, and stair risers can be up to 8.25 in. Stairs: risers up to 8¼ in. on treads at least 9 in. deep (Pennsylvania's amendment to R311.7.5); the IRC's 7¾ and 10 are the stricter figure where an inspector asks for it.

What decks are built of in Pennsylvania

Most used on decks in New York, New Jersey and Pennsylvania: capped composite, then treated pine, then PVC.

Sales tax in Pennsylvania

Pennsylvania's base state sales tax is 6%, and cities and counties can add their own. How it applies to a home-improvement contract varies, so ask whether a quote includes it. Prices on this page are before tax.

What a King of Prussia contractor will ask before quoting

  • Reuse the frame or rebuild?
  • Height, railing style and stairs
  • Board brand and color

Deck building cost in other Pennsylvania cities

A 300 sq ft deck with pressure-treated wood averages $12,200 in King of Prussia; $12,200 in Philadelphia, $11,900 in West Chester, $11,400 in Pittsburgh.

CityAverage · range
Philadelphia, PAsame as King of Prussia$12,200$8,400 – $15,900
West Chester, PA2% less$11,900$8,250 – $15,600
Pittsburgh, PA6% less$11,400$7,850 – $14,900
Harrisburg, PA5% less$11,600$8,000 – $15,200
Allentown, PA5% less$11,600$8,000 – $15,200
Lancaster, PA11% less$10,800$7,450 – $14,100
Scranton, PA10% less$10,900$7,550 – $14,300
Erie, PA13% less$10,600$7,300 – $13,800

deck building price in King of Prussia: questions

How much does it cost to build a deck in King of Prussia, PA?

About $12,200 for a 300 sq ft deck with pressure-treated wood, and most King of Prussia quotes fall between $8,400 and $15,900. That is 8% above the U.S. average, where the same job averages $11,300.

What is the deck price per square foot in King of Prussia?

$28 to $53 per sq ft, about $41 on average with pressure-treated wood. Smaller jobs cost more per unit, because the fixed costs are spread over less.

How much is a 400 sq ft deck in King of Prussia?

$10,800 to $20,300, about $15,600 on average, with pressure-treated wood — $39 per sq ft.

Do you need a permit for deck building in King of Prussia?

Yes — a new deck needs a permit nearly everywhere, King of Prussia included. In Pennsylvania, decks follow the Pennsylvania Uniform Construction Code — residential (2021 IRC with Pennsylvania amendments). The prices on this page carry $400–$1,200 for plans, permit and layout.

Does the price include sales tax in Pennsylvania?

No. The prices here are before tax; Pennsylvania's base state rate is 6%, plus any local rate.

What decking do people choose in Pennsylvania?

Most used on decks in New York, New Jersey and Pennsylvania: capped composite, then treated pine, then PVC.

How these prices are built

Every price on this page comes from JobFlex's contractor price book: what a homeowner pays a licensed contractor for each step of the job, as a U.S. national average per unit, with the contractor's overhead and profit included and sales tax left out. The deck building is priced step by step, then multiplied by King of Prussia's construction cost index of 1.08.

Where the price book's steps for an option add up to more than 20% over the installed price a published source gives for the whole job, every step but a permit fee is scaled down to the middle of that range: pressure-treated wood × 0.74 (HomeGuide 2026: $25–$50 per sq ft); capped composite × 0.80 (Ergeon 2026: $30–$60 per sq ft).

The index weighs local construction wages (BLS Occupational Employment and Wage Statistics, May 2025) at 60% and the area's material prices (Craftsman ZIP-area factors) at 40%. Published indices for King of Prussia, each on its own base: Craftsman 1.10. Treat any city figure as about ±5%; a contractor's quote for your house is the number to plan with.

Contractors in King of Prussia build quotes like these with JobFlex's Deck Studio.

  • HomeGuide 2026: pressure-treated deck $25-$50/sqft installed, labor $15-$30/sqft
  • Ergeon 2026: composite deck $30-$60/sqft installed
  • HomeGuide 2026: composite railing $25-$60/lf, aluminum $50-$200/lf installed