Measure out and mark the outline of the deck, then measure out and mark where the concrete piers will sit. When laying each pier, make sure they are no more that 6 feet apart.
Note: Check local building codes as they may require that you use more than just piers.
If the area is covered with grass, cut out the sod so that the pier will sit firmly on solid ground. Use a tamper to compact the ground for the spot where each pier will sit. This will make sure that the earth is solid enough to support the weight of the deck.
Lay the girders in the joist hangers of the concrete piers. Take a level and set each end on a separate girder to make sure they are both the same level. If they are not level, take a tamper and beat down the soil of the higher pier until it is level. If this doesn't work, place shims underneath the girder to raise it to the appropriate level. Make sure that all the joists are even by placing the level between each joist.
With the girders in place and level, attach them by nailing into the joist hangers on top of the concrete piers.
Lay the cross beams out 16 inches from the center over the girders. Since this deck will have an angled side, the first four beams will be 136 inches long, the fifth beam 127 1/2 inches, the sixth beam at 111 1/2 inches, the seventh beam at 95 1/2 inches, the eighth beam at 79 1/2 inches and the final beam at 63 1/2 inches. Attach these to the 4 x 6 beams with joists hangers.
Once the cross beams are in place, it’s time to secure it with the deck frame. Place 2 x 4s along the ends of the cross beams on each side of the deck and secure them with framing nails. Then add joist hangers where the frame and the cross joist intersect. Because this deck has an angled side, miter the ends of two frame beams that will sit on either side of the angle to 45 degrees. Place the beam that runs along the angled side and attach it with the framing nails.
To trim the girders, take a chainsaw and cut the end of the girders that extend past the edge of the frame.
Use a deck guide when placing the decking. This will assure that each piece is uniformly spaced. For this project, decking was spaced 1/4-inch apart.
The deck guide will also help align the spaces for the predrilled holes. Drill into the beams where it meets the frame using 2 1/2- inch composite deck screws. Continue down the line. When nearing the end, adjust the deck spacing if necessary to leave a 1-1/2 inch overhang on the opposite side.
Use a circular saw and trim along the chalk line, making the jagged side of the deck nice and straight.
Use prefabricated risers for the stairs. Cut a section big enough for the cross beam to fit, starting at the base of the third step. If the riser is too big, trim the bottom of it until it fits. Make sure all the risers sit completely level. Once in place, drill 4-inch screws through the cross beam and into the portion of the riser behind it. For extra strength, add front and back 2 x 4s in for each level of stairs. Attach the rear 2 x 4s of the second step to the frame.
Add the decking material to the stairs. Take the 12-inch deck facing and cut to measure (if needed) for each side of the deck. Miter the ends of each piece so they form clean corners. Place the facing on the outer side of the frame so it skirts around the deck. Attach it using 3-inch galvanized framing nails.