How to Build Stairs

If you think building stairs is hard, think again. Building stairs are easy to do for anyone with moderate carpentry skills and a few power tools. Whether it’s a deck, porch or shed, building stairs is an easy task, but is certainly a challenge if you’ve never built a set of stairs before.

To begin with, you need to have a deck to landing measurement. Take a long string or long board from the top of the deck and extend it over the area that is going to be your landing. Take a measurement from the bottom of your board or string line and measure down to your landing. Let us say the measurement comes to 60″. The next job is to find how many times 7″ (the typical tread height) divides into 60″. The answer comes to 8.5 so the total steps on our staircase after we round down comes to eight steps.

Now determine the height of the rise of each step by dividing the 8 steps into 60″. The answer is 7.5 or 7 Ã?½”. Now we know that or rise height will be 7 Ã?½”. To calculate our tread length we need to find the length of the total “run” or the overall horizontal length of the stairway. We simply multiply our number of steps (8) by the 10″. We use 10″ because it is the optimal run of an average step and it allows two 2×6’s to fit on each step and hang over approximately 1″. That means the over all run is 80″.

Measure to 80″and make a mark on an eight-foot long 2×12. Now on a framing square, find 7 Ã?½” (our rise height) on one side and 10″ on the other side and clamp on stair gauges on each side of the framing square. These small brass clamps screw on to the framing square and hold it in place so you can achieve an identical mark each time. Mark the square with a pencil for the tread and riser. Slide the square down the stringer and align the square with the previous notch. Mark the 2×12 to the end of the 80″ mark. Once that is complete, go back to the first tread you marked and remove 1 Ã?½” from the step. If you’re using 2×6 for your steps 1 Ã?½” is the thickness of the 2×6, other calculate the thickness of your steps. (5/4 decking board = Ã?¾”)By removing the 1 Ã?½” from the risers first step, you ensure each step is identical in riser height.

Cut the steps using a circular saw and finish cutting the stairs with a hand saw or jig saw to prevent over cutting of the stringers. Use the cut set to use as a pattern for other stringers. Usually a set of stairs is no less wide than four feet, but you can go as wide or as short as you really want as long as you space each run no less than 16″ apart. Toe-nail each finished stringer to the cleat and face of the deck using screws or nails.

Now cut the steps. Make sure each step over hangs the outside stringers by about 1 Ã?½” on each side of the staircase. Attach the two steps to the stringers using screws or nails. Now cut the risers and attach them using screws or nails as well. You don’t really need risers but it does prolong the life of the stringers by concealing the cut portion of the 2×12 stringers from the weather and elements. Finish tall stairs by adding a railing or you can leave smaller heights as they are.