How to Build a Deck With Fir or Redwood

Contact your local building code administrator, so that you comply with all local building codes. Codes vary among jurisdictions. Some areas require a building permit for decks regardless of size or height. Others require railing on decks that are more than 18 inches from the ground.

Lay out your deck on the ground according to your plans. Stake the deck area’s corners with wooden stakes. Attach string around the perimeter at the appropriate height for your deck. Use a level to ensure proper height at all corners. Measure the height at each corner as the length of each post may vary based on the landscape.

Set concrete footings in place at each corner. Use the measurements you took earlier and cut the 4-by-4-inch redwood or fir posts to the appropriate lengths. Install the 4-by-4-inch posts into the concrete footings and secure them by toenailing through the wood, nailing block onto the footings. Using a carpenter's level ensures that the posts are plumb.

Cut your 2-by-10-inch skirtboards and 2-by-4-inch ledgers to length. Position the long-side skirtboards so that they extend 1 1/2 inches above the corner posts. Drill two three-eighths inch holes through the skirtboards and corner posts. Attach the skirtboards to the corner posts with three-eights-by-6-inch carriage bolts, washers and nuts. Position the ledgers 1 1/2 inches below the short-side skirtboards' edges. Attach the ledgers to the short-side skirtboards with three-eights-by-2 1⁄2-inch lag screws. Position the short-side skirtboards so that they extend 1 1/2 inches above the corner posts. The ledgers should be positioned toward the inside of the deck and even with the posts. Drill two three-eighths inch holes through the skirtboards and corner posts, staggered to allow for the lag bolts in the long side skirtboards. Attach the skirtboards to the corner posts with three-eighths-by-6-inch carriage bolts, washers and nuts.

Cut your 2-by-8 joists to length. Nail joist hangers to the long-side skirtboards’ inside of the using 1 1⁄4-inch joist hanger nails. Joist hangers should be evenly spaced, approximately 24 inches apart on center, and low enough to allow the joists to settle 1 1/2 inches below the skirtboard’s top. Install the joists into the joist hangers.

Layout the redwood or fir decking boards on top of the joists, but do not attach them yet. Rearrange the decking boards until you are satisfied with the pattern, leaving one-eighth inch between decking boards. Once you like the deck’s appearance, predrill pilot holes through the decking boards to help prevent splitting. Attach decking boards to the joists and ledgers with 3-inch deck screws.