Building A Precut Or Pre Made Deck Stair Stringer
The typical deck stair is made of stringers and wooden treads. The stairs can be built between two deck levels or between one deck edge and a concrete stoop at the bottom. Cutting the wood stringers for steps on a deck takes exact calculations and skill. However, using standard carpentry tools and stair-stringer gear, a novice deck builder with some carpentry expertise can install a set of precut stringers. Taking measurements and obtaining the precut stringers from a woodworking shop or lumber supplier is the first step. Stringers can be put in depending on the width of the staircase or closer together if the stair treads extend 2 inches or more past the stringers' edges.
Things Needed
- Stringers, Measuring Tape, & Level
- Stringer Joist-Hangers & Joist-Hanger Nails
- Framing Hammer & Framing Square
- Two-By-Six Pressure-Treated Lumber
- 16d Galvanized Nails & Power Drill
- 3/8-Inch Carbide Drill Bit
- 3/8-Inch By 4-Inch Expanding Anchor Bolts
- Socket And Ratchet
Step 1: Measurements And Ordering
- Measure The Rise
Measuring the rise of the steps will allow you to determine the amount of treads and risers on the stringers. Rise is the vertical distance between the surfaces of an upper and lower deck, or between a deck's surface and the ground. - Make The Stringers
Give the lumberyard or woodworking business the rising measurement. The store or business will create the stringers by notching pieces of 2-by-14-inch framing lumber for each step. For steps that are up to 30 inches wide, get two stringers. For stairs that are wider than 30 inches, order an extra stringer for every 24 inches of width. For instance, 60-inch broad stairs need four stringers, while 48-inch wide stairs need three.
Step 2: Installing The Stringers
- Position The Stringers
Place the lower end of a stringer on the lower level of the deck and the upper end of the stringer up against the face of the rim joist at an upper deck. Place the upper edge of the steps on the rim joist at the deck's edge with the bottom end on the concrete stoop for stairs that lead from the deck to the stoop. - Mark The Edges
To align the uppermost edge of the stringer with the upper edge of the rim joist, raise or lower the upper end as appropriate. When installing the stringer joist-hangers, mark the face of the joist where the bottom edge of the stringer meets the joist. At the reference mark, draw a horizontal line on the face of the rim joist using a level. Mark the locations of each stringer at the horizontal line using the stringers' spacing as a guide. - Attach The Hanger
With the nailing flanges on either side of the hanger against the rim joist, place a stringer joist-hanger vertically at the face of the rim joist. Align the horizontal line with the pocket at the bottom of the hanger. Using joist-hanger nails in each of the machined holes on each flange, fasten the hanger to the face of the joist. Use a framing hammer to drive the nails. Install the remaining hangers at the indicated positions on the face of the rim joist by repeating this procedure. - Attach The Stringers To The Hangers
Put the upper end of a stringer against the face of the rim joist and into a hanger. Drive hanger nails into the matching sides of the stringer and into each of the machined holes on the hanger's sides. Repetition of this process will result in the remaining stringers' upper ends being attached to the sides of the hangers. - Align The Stringers
Place the framing square's shorter leg on the face of the rim joist and the longer leg against the side of the stringer. With one hand holding the square in place, align the stringer so that it is square with the face of the rim joist or exactly perpendicular to it. Along the lowest border of the stringer, make a mark on the deck or stoop below. Repeat this process, then mark the lower margins of each of the remaining stringers and position them squarely against the rim joist. - Determine The Block Lengths
To calculate the length of blocking for the lower ends of the stringers, measure the distance between the top ends of the stringers. Cut a piece of pressure-treated two-by-six framing lumber to length using a circular saw using two stringers. When there are three or more, cut the pieces according to how far apart the stringers are. A post-and-beam support system or interim blocking may be needed for longer stringers. To find out if additional blocking or support is required, speak with your neighborhood building department. - Attach The Stringers To The Blocks
At the lower end, lay the 2x6 block (or blocks) flatly between the stringers. By inserting two 16d galvanized nails through the side of each stringer and into the matching end of a block, the stringers are fastened to the ends of the blocks. - Attach The Blocks
Marks on the deck or stoop should be used to align the stringers. Six inches from each end, place pairs of 16d nails to secure the blocks to the wood deck's surface. For a concrete stoop, drill holes through the face of a block and 2 inches into the concrete at 6-inch intervals using a power drill and a 3/8-inch carbide drill bit. Each hole should be filled with a 3/8-inch by 4-inch expanding anchor bolt, and the nuts should be tightened with a socket and ratchet.