How Much Does it Cost to Build a Composite Deck?

Get a Deck Material Cost Estimate with the Cost Calculator Tool

Plug in your deck dimensions below and answer a few questions to get a quote for your new deck.


Four Factors That Impact Deck Pricing

The size of your deck makes a big difference in pricing. It helps determine the materials and labor costs needed to build your deck.

The design, shape and chosen product line for your deck will affect material and labor costs depending on its complexity and price point. 

Decking materials could include a substructure, decking, railing, hardware and any design-based add-ons. Depending on the condition of a current substructure, this can also be a size-able portion of cost.

Labor and management account for nearly two-thirds of total costs no matter your deck design. We can help you find a builder or you can build it yourself.

Decking Decisions: DIY Deck Build or Hire a Deck Contractor?

Your choice will affect costs, time and responsibility. We're here to help you figure out what's best for you.

If you choose to DIY, the total cost to build a deck typically amounts to less than it would to hire a professional. However, you'll be responsible for buying (or renting) the necessary tools and materials, planning deck dimensions, obtaining building codes and more. Take our quiz to see if you're ready to DIY.

If you hire a contractor, you'll save time, energy and money on equipment. You'll also have a trusted partner with extensive building knowledge to help you see your project through. However, you'll need to consider the professional's rate and fees associated with your project. 


How to Determine the Cost of Building Your Own Deck

Determine Square Footage

First things first, determine your deck’s square footage by multiplying the length of your deck by the width. Don’t forget to factor in any additional areas like stair landings and odd shapes. 

Factor in Materials

Gather the Trex® decking and materials needed for your DIY build, including your Trex Hideaway® Hidden Fasteners and railing

Use Our Cost Calculator

To receive an estimated cost for your materials, use our Cost Calculator Tool. Just plug in your deck dimensions and answer a couple of easy questions. 

Find Your Building Codes

Keep in mind, there might be costs associated with obtaining your local building codes. To find the latest building codes and procedures for your area, visit your local government website or contact them directly. 

Stock Up on Equipment

Do you have the tools and equipment you need? If you’re starting without a wood frame, you might need more than you think, but you can often rent equipment from your local hardware store. 

Keep Time in Mind

Time and energy can be overlooked expenditures. Depending on the complexity of the deck design, expect to spend several weekends with hard (but gratifying) work on preparing the site and building your new deck. 


How to Determine the Labor Cost of Building a Deck

Consider Professional Rates

If you hire a contractor, your deck size and design (such as a picture frame design, stairs or a multi-level deck plan) will likely affect your contractor’s rate or total labor costs. 

Choose Wisely

When it comes time to pick your contractor, there are a few factors to consider to ensure the best return on your investment. Discover helpful hints and best practices here

Services and Fees

Common services and fees associated with a professional build include consultation, permits and licensing, site preparation, insurance and the actual labor cost per hour to build your deck. Each professional has their own rates, but keep reading to learn more about estimating labor costs.

Hire a TrexPro®

Looking for a builder versed in all-things-Trex? Hire a TrexPro®. These builders are equipped with talented insight from previous Trex deck projects. Find a Pro near you

Labor Cost to Build a Composite Deck

Professional labor costs will vary based on the location, size and complexity of your deck build. Understanding how to estimate these costs will help you decide whether hiring a professional or DIY is best for you. Let's look at the estimate of a few common deck sizes. 

How much does a 14x20 deck cost?

Factor in the price of the Trex materials needed for 280ftof decking area. Then, use the Cost Calculator to determine how much this will cost depending on your selected decking line. The labor cost for a professional to install a composite deck runs from $25-30 on average* per square foot. This average is based on the labor cost to build a ground-level deck (not including costs associated with installing railing or a substructure). Labor costs depend on a contractor's specific rates and fees, but a good estimate is $4,200 to $8,400* total on a 14x20 deck. This doesn't account for additional fees and services like a consultation.


How much does a 16x20 deck cost?

Follow the same method for a slightly longer deck. Here, we'll be working with 320ft2 of deck area. You might expect professional labor costs to be around $4,800-$9,600*. You can see how even a small increase in your deck size can have significant cost implications.


How much does a 20x20 deck cost?

A 20x20 deck is a total of 400ft2 of materials and will likely run you upwards of $6,000-$12,000* for professional installation.


*Source: HomeAdvisor "How Much Does it Cost To Build A Deck?" 2022

Building within a budget?

  • Do it yourself or hire a deck builder in the off-season to save on installation fees.
  • Opt for straight sections of decking and stairs over more complicated curved designs.
  • Creative design and decor, like a mix and match color scheme, will add style without increasing costs.
  • Look into financing options to put the luxury deck you want within reach.
  • Get more use out of your space with efficient features like outdoor storage solutions.

Want to add a little extra?

  • Trex® Railing allows you to lean into the view without obstructing it.
  • Conceal rough edges and bridge unsightly gaps with Trex® Fascia a subtle and sophisticated finishing touch.
  • Trex® RainEscape® doubles your usable outdoor space since it drains rain and snowmelt to keep space below your deck dry and usable.
  • Trex® OutdoorLighting™ transforms your outdoor space from invisible to inviting, keeping the party going long-after the sun goes down.
  • Available in an array of modern to more traditional styles, Trex® Outdoor Furniture™ is superbly crafted, durable and oh-so comfortable.
  • Trex® Pergola™ can add elegance, charm and a little shade to your outdoor oasis.
  • Trex® Lattice™ adds a deckside dimension of privacy and utility.

Trex is here to make the job easier.

Ready to DIY?

From style inspiration to detailed how-to videos and installation guides, find everything you need for your DIY build at Trex® Academy™

Want to leave it to the professionals?

We've got you covered there too with a trusted network of TrexPro® builders ready to make your deck dreams come true. 

*Average price range excludes Trex Signature® decking, our luxury decking collection. Trex actual material costs and install costs can and will vary based on geographic area, site location, seasonality, design complexity, whether the product is stocked locally, and additional features such as stairs, angles, curves, lighting, etc. For most professionally installed projects, materials constitute up to one third of the total cost.

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