How to Construct Wooden Decks

Once you are satisfied with the planned design of your wood deck, you can select the materials to be used. Pressure-treated lumbers like Southern pine, redwood or cedar are usually the most common types of wood used, and are often the best choice for the substructure. For the visible parts of the deck, the type of wood used will depend on your alloted funds and design preferences.

While there is no such thing as a typical deck, the instructions that follow are generally for decks attached to a house that are no more than 6" off the ground, with no other exceptional load requirements. Keep in mind that the design estimates and recommendations mentioned below are suggestions only; always build in accordance with your local building codes.

Materials

First decide on the decking to be used, and determine the joist size and beam size. Pressure-treated lumber is not as expensive as redwood or cedar; it can also be used for the substructure even though other wood types will be used for the decking and railing. For pressure-treated lumber, you can choose between 5/4 x 6 decking or 2" material.

The spacing between joists will be determined by the size and species of the decking that you chose. Common sizes used for joists nowadays are 2x6s through 2x10s. It is always a good idea to first finalize the spacing between beams and then use a suitable joist size for that spacing.

Once you have determined the beam size, the posts should be spaced no more than 6' apart, with beams no more than 12' apart. This is due to the fact that support posts also serve as railing posts, and are usually run through the decking.

Preparation and Layout

The ground under the deck should first be arranged by removing the sod. To keep weeds from growing, enclose the ground with six mil black polyethylene once the deck is finished. Spot the position of the ledger along the wall for evaluation; keep in mind that as long as your layout is consistent, the way you set the joists won't really matter.