How to Build Stairs for a Deck

Building stairs for decks seems complicated at first but once you understand the formula you will become a pro in no time at all.
Decks that are above 8 inches from the ground will need at least one step. If three or more steps are needed, you'll need to build a stairway in which the steps are attached to stringers. Stringers are usually made out of 2 x 12s that are attached to the deck with deck joists at the top end and rests on a footing at the bottom. These are the part of the stairs tow which the steps will be attached. Building stairs, especially in longer runs, can get tricky. There are plenty of mathematic formulas to help you create your design, but in the end it usually comes down to trial and error. To build a comfortable set of stairs, you'll need to find a suitable rise-to-run ratio. Rise is the height between the steps and run is the depth of the step. As a rule, the tread width (run) in inches plus twice the step height (rise) should equal 24 to 26 inches.

Things You'll Need

• tape measure,cicular saw hand saw,cordless drill, a square,

Instructions

1. Measuring for Stairs: To find the correct run and rise and the number of steps needed, first measure the vertical distance between the deck and the ground. Divide the total rise by the rough riser height of 7 inches which is a good starting point. The calculation will give you the number of stairs you will need. This is a rough estimate because this formula usually results in a number of steps that is not a whole number. If this is the case, divide the whole number of steps into the total rise to get the exact riser height. Next, multiply the exact riser height by two, then subtract it from the overall ratio figure of 24 to 26 inches. This will give you the ideal tread depth in the 10- to 12-inch range. Then calculate the total run, or span, by multiplying the tread depth by the number of risers minus one, since the top step is the deck surface.

2. . Measure the overall rise between the deck surface and the ground. Be sure to allow for the thickness of the decking you plan to use in your calculations. Using a framing square on your 2 x 12 inch stringer, use your run / rise calculations. You can use a piece of tape at the run and rise measurements so it can be a quick reference. Mark an X on the waste side of the stringer so the layout stays correct.

3. Cut out the stringer with hand saw or circular saw. If using a circular saw where the blade won't reach the corners, finish those corners with a hand saw . Set the stringer into place on the deck to see if it fits your calculations. Then use it to mark the other stringer or stringers and cut them to shape. Install a stringer every 16 inches along the width of the stairway.

4. Set bottom of the stringers should rest on a cement footing which is level with the stringers. The footing can either be a poured cement base or pre formed cement slab bought at your local lumber yard.

5. . Now you are ready to install the treads (steps) to the stringers. You already know the width of the treads from the construction of the stringers. Two 2 x 6s will work great in most cases or you may use the same decking boards you used on the top of the deck. Cut the treads to the desired length and attach them to the stingers using galvanized decking screws.

Tips & Warnings

• Quality built stairs accent your deck.. By careful measuring and some trial and error, you will be able to accomplish this task. And in return, you gain knowledge, experience and a well-built set of stairs.