12×16 Deck Materials & Cost Calculator

Confirm and mark the 12 × 16 ft footprint, drainage, access and finished height. For this freestanding deck, lay out the complete supporting footprint independently of the house.

Use A1 on your diagram as the reference corner. Set batter boards or stable stakes, run mason lines, square the perimeter, then transfer every labeled footing center from the plan.

Excavate every verified footing location before beginning any concrete placement, keeping each hole centered beneath the layout lines. Prepare forms or bases required by the approved detail, expose firm undisturbed bearing soil and remove loose soil from the bottoms. Keep the full footing layout visible so all hole locations, depths and dimensions can be checked together before the pour.

Before placing concrete, verify every footing hole is complete and obtain any required footing / excavation inspection. Recheck hole locations, dimensions, bearing conditions, forms and reinforcement required by the approved detail. Then mix and place concrete according to the manufacturer instructions. Consolidate and finish the top, then accurately position approved anchors or post bases. Allow the concrete to cure before loading it.

Set posts in the cured post bases, plumb them in both directions and temporarily brace them. Establish consistent reference elevations before final cuts or loading the supports.

Assemble and install beam members at the verified elevation using approved post-to-beam connections. Provide the required direct bearing at posts, restrain beams against lateral movement, and keep splices only over approved bearing locations. Keep the beam straight and level before final fastening.

Using the independent beam/post support system already installed, build the rim/end framing at the established elevations and square the complete structural perimeter. Keep the house-side frame structurally independent of the house with the clearance required by the approved design, and temporarily brace the frame until the joists make the assembly stable.

Start from one reference edge and mark every joist center at 16 inches on center. Do not chain measurements from joist to joist; measure each mark from the same origin, then cut, crown and fasten the joists.

Install required blocking, lateral restraint and remaining framing connectors before covering the frame. If guards or stairs are required or included in the approved design, install their structural blocking, post/load-path connections and other concealed reinforcement now while the framing is accessible. Recheck fastener schedules and use corrosion-resistant fasteners compatible with the lumber and connectors.

After required framing inspections and concealed guard/stair reinforcement are complete, start from a straight reference and install boards perpendicular to the joists. Follow the selected decking manufacturer requirements for joist spacing, gaps, fastener pattern, edge distances and allowable overhang. Check alignment every few courses. After the field boards are secure, snap a straight trim line, cut ends consistently and complete required fascia / edge details.

Complete every required guard, handrail and stair assembly using the structural blocking, posts and load-path connections prepared before decking. Verify stair geometry, landings, guard/handrail details and openings against the approved design and local requirements.

With construction complete, inspect accessible structural connections, guards, stairs, handrails, fasteners, board spacing and finished edges. Correct defects, clean the site, complete any required finish or preservative work, and obtain the required local final inspection before normal use.