2. Cut two 2x4s to 96 inches for the front and back pieces and cut four 93-inch boards for the ends and two crosspieces. (The ends and crosspieces are 3 inches shorter to allow for the 1-1/2-inch thickness of the front and back boards.)3. Lay out the frame on the pieces of decking (figure A). Before attaching 2x4s with wood screws, make sure the ends are perfectly flush. Use shims to raise a board if necessary (figure B).
4. Drill pilot holes for screws then insert screws (figure C). If you have an assistant, things can go faster by having one of you drill pilot holes while the other follows and inserts screws. If the wood is damp and the screws are difficult to drive in, coat them with a little dishwashing liquid first.
5. Check to see if the frame is square by measuring the diagonals (figure D). The two measurements should be equal.
6. Flip the frame over and attach scrap 2x4 blocks at each corner to serve as feet for the deck (figure E).
7. Move the frame to the laundry room and level it with shims or plywood. For added stability, attach 2x4 supports under the centerpieces. Insert screws at an angle through the supports and into the feet (figure F).
9. Position the plywood decking in place and use a chalk line to mark the position of the supports underneath. Secure the decking to the supports with screws.
9. Replace the washer and dryer on the platform.