How Much It Cost to Build a Deck

Based on the choice of materials, and the layout of the deck, prices for it's making will vary considerably. Decks made of pressure treated pine are about the most popular and economical of selections, all lifespans aside. But there are other kinds of woods and synthetics, such as composite.

The more apparent features and deck patterns will factor enormously in the cost. Such as the chosen style of rails & caps, if there are stairs or stepped sections, and any attached seating along with the overall shape (including if the deck is squarish, L shaped or custom). Although typically, a 12' by 14' contractor-built deck will range from $22 to $35 a square foot to amount to a total cost of $4,788 on average. Favoring lower prices if at ground level, higher when there are intricate or more elaborate designs, diagonal floor slats, or when the deck is elevated.

Deck Alternative Pricing

Decks by Contractors - those that are experienced are usually most efficient at building, in addition to any safety and structural concerns. And, what are less obvious elements to many consumers can definitely matter after the job is done. Some decks, particularly having taller or raised platforms, can bring sway and bounce that should be eliminated preferably during planning and with the proper know how. Then there is the doubling of select joists, where needed, or other placements of support. Sidestepping floor slat deformation and other undesired movements.

Consulting with a qualified decking contractor should reveal all dimensions, that in turn, determine bottom line costs. For example, 2"x 4" pressure treated decking might be of another width. Or the 4" by 4" support posts may be increaed to 6" by 6" instead for greater support capacity and stoutness. All of which are calculations that can change lineal footage figures and appearances. Thus, obtaining options on the initial estimate, only where advisable, can provide cost alternatives for the amounts being spent.

Building Yourself - only thost that are experienced at carpentry and framing should attempt constructing a deck, even less so for other materials like composite and vinyl. But those that do, can stand to save 45% to 70% over the cost of hiring a professional for the wood deck. However the inexperienced usually take blocks of time for the same procedures. Which assumes a basic understanding of the process to begin with; for example, just on the floor slats - which grain side goes down, the recommended gap widths, and the fastener placements - and stair construction demands other skills. But about cost, reduced savings are typically captured on a percentage basis when setting non-pressure treated decks; such as redwood & cedar, epi and other exotics along with composite materials or for vinyls due to the handling of the materials.

Materials/Supplies - many decks have the same material components in common. Yet some of the 'must haves' normally are: support piers, concrete mix (yielding roughly 1 cubic foot per bag at $3.60 each for a 4,000 psi mix, on to $5 per bag for high strength blend). Pouring tubes are roughly $5.50 a piece, these manually cut to size and then there is a possibile gravel base with gravel at $3.40 per 50 lb loose bag. For piers that should be set below the frost line, which will vary depending on soil & location.

Pressure treated 2 x 8 headers and joists are approximately $1.05 to $1.20 L.F. depending on their length (at 10', 12' and 16') and place of purchase. Adjoining joist hangar ties are close to $1.10 ea..

Stairs - precut stair stringers in pressure-treated go from the basic two step option, that is close to $7 for each single unit pair, up to 6 and 8 steps for around $18. Against the alternative of laying out the treads, risers and their angles by hand (forming at least one for a template) and then sawing.

Attachments, in the form of treated #8 and #10 deck screws run about $30 per 5 lb box, that should be enough for a modest size deck (where screws are used in combination with nails based on the attachment schedule) or else $8 to $10 for a single pound box. Galvanized carriage bolts, for cinching at upper posts, for example, cost less than a couple dollars each when bought in quantity.

Bumping the Finished Deck Bill

Always be sure to check local codes for specific material orders and installation requirements:

• Normally the routing of any electrical lines, such as for outdoor outlets, are excluded from quotations.


• Placements of deck lighting, and gas lines like for gas grills are usually also excluded from estimates unless specified.


• Staining or sealing the surfaces is traditionally extra. See deck staining cost.


• Constructing landings beneath the stairs are not part of most estimates although these may have to be done first before the stairs are built.


• Certain style staircases affect costs. Some take their own support. Lower cost options of ingress and egress can frequently be investigated.


• Demolishing and disposal of an existing deck may or may not be included. But either way should be itemized.