Build Deck Cost

How much does it cost to build a deck?

The average deck is constructed from three features - the planks, the framework, and the railings. These can be made from wood or from composite materials. The costs between the two options will usually serve as the overall deciding factor. While wood comes in at a much lower price, the composite materials can often be relied upon for a much longer lifespan. The composites, however, can be somewhat difficult to work with.

For the purpose of this conversation we will consider the costs and requirements for the construction of a wooden deck measuring 16'x20'. According to the Hanley Wood and their Remodeling Online website, the cost for a wooden deck addition averages at $10,634 or $33 per square foot. Remarkably, the project has an impressive resale value, and a homeowner can reasonably expect to recoup around 80% of the total construction costs for such a deck at the time of sale.

Cost breakout

Is it a DIY project? Not really, the average homeowner is not going to have the advanced knowledge of carpentry and concrete handling that will be demanded by such a project.

The costs for the project will include:

  • Materials - the deck described would require pressure treated joists, 4"x4" pressure treated posts, pressure treated decking installed in a basic linear array, and appropriate galvanized screws (usually around 15 pounds) to complete construction;
    However, there are regions where the pressure treated wood is not used for anything except for the framing portion of the decks.
    Other choice of deck materials includes Redwood, Douglas Fir (pre stained), any of the Hardwoods, Ipe, Mangaris, etc... as well as all the composites.
  • Excavation and site preparation - costs will vary according to the level of work necessary, but all projects will require leveling and the insertion of fiber form tubes for the concrete footings;
  • Concrete - the posts used as the framing for the structure must be set into concrete footings. Concrete is priced at an average of $75 per cubic yard, and this would mean that one to two yards would be required for the work;
  • Stairs and railings - in most regions it would be illegal for any carpenter or contractor to construct a deck without also ensuring that a set of stairs and safety railings were in place too. The stairs for a ground level deck would usually include only three steps, and the railings would need pressure-treated wood posts, railings, and balusters;
  • Furnishings - the cost of the deck should include built-in benches and planters made from the same pressure-treated materials as the decking itself.

Enhancement and improvement costs

  • Stain or seal - even if the decking is pressure treated it may be a good idea to seal or stain it against the weather. This is especially true for homeowners in areas where summer temperatures can be high and yet where winter weather includes a lot of precipitations and freezing temperatures;
  • Electrical service - most decks should have at least a single electrical outlet appropriate for outdoor use. This will allow the homeowner to have access to such service without running extension cords into the home or the basement; and
  • A pergola or awning - unsheltered decks can become unpleasant during the worst of the warmer weather. For a few hundred dollars the homeowner can often have a fabric awning (which is retractable) or a simple pergola installed on the deck too.