How Long Should My Stair Stringers Be?
When building deck stairs, you will need to determine the total height of the deck at the stairs. This is the change in elevation from the top of the deck to where you expect the stairs to land. Place a level straight out from the deck and measure to the ground or landing using a tape measure.
You also will need to establish the tread depth and riser height for each step using our Decks.com Stairs Calculator. The minimum tread depth is 10" and the maximum riser height is 7-3/4". The Stairs Calculator will also provide you the length of the 2x12 stair stringer you will need to use and the angle of the stairs.