In this video, This Old House general contractor Tom Silva explains how to build deck stairs.
Steps for building deck stairs
- Determine the width of each stair tread.
- Use 4-foot level and tape measure to find the total rise of the staircase.
- Divide total rise by number of steps to find height of each riser.
- Set framing square and straightedge to height of riser and width of stair tread.
- Use framing square to mark saw-tooth pattern of steps onto a pressure-treated 2×12.
- Notch the stringer with a circular saw, being careful not to saw beyond the cut lines.
- Finish cutting the stringer with a handsaw.
- Use first stringer as a template to mark the remaining stringers.
- Trim upper, rear edge of each stringer the thickness of the risers.
- Trim bottom end of each stringer the thickness of the treads.
- Fasten the first and last stringers to the deck frame with L-brackets.
- Fasten the intermediate stringers with 3-inch decking screws driven through the deck frame and into the rear of the stringers.
- Attach risers to stringers with 3-inch decking screws.
- Install 4×4 railing posts with 3-inch screws.
- Use jigsaw to notch treads to fit around railing posts.
- Fasten treads to stringers with decking screws.