How to Build a Flat Deck
- 1). Cut the pieces of 2-by-12 for the frame under the deck with the circular saw. Leave six pieces at 10 foot and cut twelve 9-foot 9-inch pieces.
- 2). Cover all eighteen 2-by-12s along with the 34 2-by-4s with wood stain or paint. Allow to dry.
- 3). Construct the first layer of the 10-foot square frame on the ground. Place two 10-foot 2-by-12s on edge parallel to each other 10 feet apart and put two 9-foot 9-inch 2-by-12s between them. Fasten the frame together with 2 1/2-inch screws.
- 4). Use two more 9-foot 9-inch 2-by-12s and insert support beams inside the first layer of the frame. Stand them on edge perpendicular to the 9-foot 9-inch sides and equally space them out between the sides. Attach the ends of the beams to the 9-foot 9-inch sides of the frame with 2 1/2-inch screws.
- 5). Repeat Step 3 and 4 and build two additional frame sections directly on top the assembled section. Build one section on top of the one on the ground, then add the third section on top of the second section. Fasten the three sections together with penny nails. The frame is 33 3/4-inches high.
- 6). Finish the deck by adding the top surface. Line up the 34 10-foot 2-by-4s across the top of the frame so they are perpendicular to the support beams inside. Drive a 2 1/2-inch screw through every 2-by-4 board at four spots - the two outer sides and the two inner support beams.
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