Decks can be broken down in several parts, each of which has its own process. These include the foundation and support structure, the framing, the decking and railings and stairway if needed. Local building departments usually inspect deck construction and require permits and sometimes plans stamped by an architect or engineer. Check with your city or town's building department for code requirements before beginning any building project or buying materials. Deck building is a moderately difficult or moderately easy project, depending on the height and size of the deck.
Your home center can help with planning. Most offer design services tailored to local building codes. Staff can design your deck on a computer, printout construction drawings, material lists and specifications that you provide to your building department. After permit approval, they'll use the materials list to deliver everything to you.
Use the construction drawings to stake out the area. Careful measurements and a square layout are essential. Set stakes in the ground and run mason lines. Use the carpenter's 3-4-5 triangle rule to keep it square. Outline with marking paint and remove the sod. Lay out the positions of the footings using mason line and marking paint.
Footings and Supports
Rent an auger to dig your footings. Add cardboard footing forms as soon as the holes are dug. Most building departments require an inspection of the footing holes before they are filled with concrete.
After passing inspection, fill the tubes with concrete mixed in a wheelbarrow or rented mixed. Pour the concrete into the forms,settling it with a long pole. Level the top with a 2 x 4 and insert J-bolts for the post brackets using the mason lines as guides. Allow the concrete a full 24 hours to cure before continuing.
Install post brackets on the bolts anchored in the concrete footings. Cut posts to length, install in post brackets and level. Attach a ledger board with 1/2-inch lag bolts driven into the house framing. Attach the beams to the posts according to the construction drawings with 1/2-inch bolts, nuts and washers. Two outside (rim) joists will attach to the ledger board and the opposite rim joist. Use the correct size joist hangers and fasteners to add these and subsequent joists on 16-inch centers.
Add posts for railings on the inside of the framing according to the construction drawings and fasten them with 1/2-inch lag bolts. Some building departments require an inspection at this point, so check requirements before continuing.
Decking and Railings
Begin adding decking planks on the edge of the framing opposite the house. Space the planks 1/8 to 1/4 inch apart and check frequently to insure they remain parallel to the house. Use deck screws coated according to the material you are using.
Railings are added between posts. Local codes dictate the space between the lower railing and the deck, the spacing of the balusters and the overall height of the railing. Typically, the openings must not exceed 3-1/2 to 3-3/4 inches. Pre-milled or formed top and bottom rails fasten with brackets and screws. Balusters are cut to fit, their spacing calculated and installed. Drill pilot holes for the screws to avoid splitting the balusters.
Building codes require all stairstep heights (risers) to be the same height. The building department sometimes dictates a formula for calculating the tread length and riser height.
Stair supports, or stringers, are cut from 2 x 12 lumber. Stringers must be no more than 16 inches on center apart. Use a framing square to mark the stringers and cut them with a circular saw. Use joist hangers to attach the stringers to the deck.
Add posts to the bottom outside stair stringers for the railings if they are required. Install treads and add the railings, checking local code requirements for stair railings.
Call for a final inspection before staining or painting the deck.