How Much Does It Cost to Build a Deck in Seattle, WA? [2025 Data]

Building a new deck is your ticket to soaking up mountain views or catching summer sunsets in the abundantly green Emerald City. Seattle homeowners can expect their deck construction costs to hover around $10,133, with most projects falling between $5,272 and $14,994, depending on size, style, and materials. 

Prices rise for modern designs, upgraded finishes, or premium materials that withstand the Pacific Northwest's rain. And of course, no matter the design, hiring a pro ensures your new deck pairs perfectly with a strong cup of local coffee in hand.

Deck Building Cost Factors 

Like Seattle’s grunge roots, deck building here isn’t polished or easy; it’s rugged, layered, and shaped by Seattle’s unique environment.

Building on flat lots is usually simpler. However, construction on a steep Queen Anne hillside or a sloped Ballard backyard often requires additional engineering and structural support, significantly increasing the price tag. Additionally, while the short, dry summers are ideal for construction, the high demand can increase labor rates during these peak building months.

The weather is another major factor. Seattle is famous for its long, wet season, meaning your deck materials must withstand months of rain, moss, and dampness. Choosing metal, hardwoods, or composites that resist rot and mold may cost more up front, but they’ll last longer and save money on maintenance, like the cost of staining a deck annually.

Size

Most new decks cost $37 to $74 per square foot. The higher end of that range represents deck projects built on second stories, building a deck with high-end wood, or customized designs. See the table below for general estimates based on the size of your deck:

Material

Your chosen deck material will make up a large portion of your total budget, ranging from $2.50 to $55. Less-expensive materials can be tempting, but they may result in extra expenses for maintenance and repair, which you’ll need to hire a local deck contractor to handle. 

Here’s a breakdown of the materials and their costs:

• Pressure-treated wood costs $2.50 to $6 per square foot 

• Composite deck materials cost $15 to $27  per square foot 

• Ipe wood decking costs $12 to $25 per square foot 

• Tigerwood costs about $9 to $18 per square foot

• Mahogany costs $10 to $14 per square foot 

• Redwood decking costs $6 to $43 per square foot

• Bamboo decking costs $4 to $12 per square foot

• Cedar decking costs $4 to $9 per square foot 

• Metal or aluminum decking costs $18 to $25 per square foot

Deck Type

Simply put, the more complex your deck build is, the more it will cost. Types of decks like wraparound, multi-tier, and rooftop decks require greater accessibility, additional prep work, and often more materials.

For example, if you want to build a floating deck, it will likely cost about $25 to $74 per square foot. These decks don’t actually float—they’re just not attached to your home. Because of this, they’ll need a few more support posts to keep them structurally sound.

Deck Height 

The type of deck you build will likely go hand in hand with where it’s installed. A second-story deck (which some contractors might deem a balcony) costs more to build because it’s harder to install. The most common place to install a deck, which is also likely the most cost-effective, is on the first floor attached to the backside of your home.

Here’s one example of how the cost average might differ:

• 10x10 first-story deck: $1,230-$2,460

• 10x10 second-story deck: $4,920–$6,150

Framing

Framing a deck, which ensures the unit's joints are structurally safe and sound, costs $11 to $15 per square foot for labor. The lumber or materials needed to frame your deck account for about one-third of the lumber you’ll need.

Flooring

Some homeowners choose to install flooring over a wood deck. Composite is a good material option, while more elegant choices like porcelain or ceramic could add thousands (or tens of thousands, depending on the deck’s size) to your price tag. The average cost ranges from $25 to $55 per square foot, depending on the material. 

Add-Ons

Here are some other costs you might incur if you upgrade from a simple deck build:

• Staircase cost: $31–$62 per stair

• Electricity cost: $160–$369 per outdoor outlet

• Outdoor lighting fixtures cost: $62–$615

• Heaters cost: $123–$369

• Outdoor misting system cost: $2,583–$4,182

• Sofa, chairs, and table cost: $615+

• Outdoor fireplace cost: $1,845–$9,840

• Retractable deck awning cost: $738–$4,305

Deck Pro Costs

Building in Seattle requires more than just sweat and muscle. Deck contractors in Seattle, WA, work in a city where rain never takes a season off, regulations rival the complexity of a Mariners box score, and rising costs match Capitol Hill rent increases. 

Local Labor Rates

Seattle’s cost of living is 45% higher than the national average. And that reality shows up in your contractor’s invoice. Carpenters, framers, and deck crews have to cover the same high rent, groceries, and yes, $6 lattes as everyone else.

That means hourly labor rates in Seattle are steeper than in most cities. But it all comes with a nice payoff. You’re getting skilled tradespeople used to building on soggy hillsides and navigating strict city codes.

Permits

Suppose your deck is more than 18 inches off the ground, built on a roof, or happens to touch an environmentally critical area, such as wetlands, steep slopes, or shoreline buffers. In that case, you’ll need a permit from the Seattle Department of Construction and Inspections (SDCI).

However, while the permitting process may feel like waiting in line at Pike Place Market on a Saturday, skipping it can result in fines and significant headaches when you sell your home.

Tipping

Seattleites are known for tipping generously, whether it’s a street busker or a construction crew. While not mandatory, it’s common to tip deck crews anywhere from $20 to $50 per worker at the end of a job, especially if they went above and beyond, like squeezing your project in before a rainy streak or hauling materials up a steep driveway.

Does Building a Deck Increase Home Value?

The average ROI for a new deck is 83%, depending on the size of your project, the neighborhood, and the materials you choose. For instance, a rooftop deck overlooking Lake Union or Elliott Bay will add more value than a small back porch in a quieter suburb.

Safety is a key factor that buyers notice, such as code-compliant builds that withstand heavy Northwest rains. Efficiency also matters; think low-maintenance composites or rot-resistant materials that appeal to buyers who don’t want to spend weekends sanding and staining.

Functionality is also a big deal. Built-in seating, planters, and shade structures add versatility, while universal design features, such as wide stairs and secure railings, make the space accessible to everyone. 

How Angi Gets Its Cost Data

Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We survey real Angi customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects. 

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