Materials needed for framing and decking are (8) 4x4 posts 10’ in length and (16) 1x3 wooden braces 4’ in length. Deck joists needed include (1) 2x6 with length of 12’, (6) 2x6 with length of 6’, (8) 2x6 with length of 4’ and (8) 2x6 deck joist headers 3’ in length. Other materials needed are 2x6 deck boards measuring 184 linear feet, and (8) 2x6 rim joists 6’ in length. Redwood used for the deck should be Construction Heart or Deck Heart grade because the deck is constructed near the ground. Corrosion resistant deck screw, 10d nails and metal joist hangers will also need to be used, again because of the close proximity of the deck to the ground.
To begin construction of the deck, measure and trim a single 2x6-redwood deck joist that will span the wide of the gazebo between opposite posts. Now attach the metal joist clips to the posts with 10d nails using a string level as a guide. The next step is to trim the center railing block so the spanning joint can sit on it. The spanning joint is not ready to attach to the posts and be toenailed to the center railing block.
The spanning joist is connected to two deck joists at 90* angles and should be level. The deck is now ready to attach four more 2x6 deck joists to the posts and the spanning joint. These deck joists should be level as they are being installed. After installation of all the joists, double check and make sure they are all level. Correct any joists that are not level. The gazebo deck should now look very similar to a wagon wheel with the spokes in place.
The2x6 headers, with ends trimmed to the opposite of 22 ½* angles are the next item to be installed. Now use 16d nails and attach the trimmed headers to the deck joists at the point where the joist span becomes greater than 24” and the headers are completely covered by a complete deck board.
After installing the headers, it is time to install the rim and intermediate joists. The 2x6 redwood rim joist ends should be trimmed to 22 ½* opposite angles, just like the headers. Now attach the trimmed rim joists to the outside of the beveled posts using two 4”, self-tapping screws per joint. The remaining eight intermediate joists, measured and trimmed to the distance between the rim joists and the headers are attach to the rim joists and the headers using joist hanger.
The frame for the decking is now complete and the decking itself can begin. Trim the deck board 22 ½* so it will be flush with the centers of the deck joists. Lay the first section of deck boards on the frame, do not trim or attach this layer at this time. Chalk lines are to be snapped across the boards along the centers of the deck joists. This chalk line is used to mark the end cuts and nailing patterns for the first layer. Space the boards using a 16d nail and now trim this layer using the chalk lines as guides. Attach the layer using 16d nails and make sure the nail heads are flush with the board surface. Finish the deck with the remaining deck boards measured and cut to match the first layer. Attach these deck boards to the joists. The final touch of the deck is to finish the center with a course of deck boards along with an octagon that is created from two halves cut from pieces of 2x6 lumber.
