Ok to make risers I saw a youtube video that said get the total rise and divide that by 7.5. That should give you the number of steps you should have to come down at a good decent. So I did 37 inches / 7.5 and got 4.9999 so I figure 5 steps. Didn't tell me how long just that I need 5 steps. So I'm thinking that the deck itself is a step so that really makes 4 actual steps, but how do you cut that? Go 7.5 inches down the board then make a cross mark to meet that 7.5 down and measure the next step from there? Sounds like a plan if it works.
"Stair riser heights shall be 7 inches (178 mm) maximum and 4 inches (102 mm) minimum. The riser height shall be measured vertically between the leading edges of adjacent treads. Rectangular tread depths shall be 11 inches (279 mm) minimum measured horizontally between the vertical planes of the foremost projection of adjacent treads and at a right angle to the tread's leading edge. Winder treads shall have a minimum tread depth of 11 inches (279 mm) measured between the vertical planes of the foremost projection of adjacent treads at the intersections with the walkline and a minimum tread depth of 10 inches (254 mm) within the clear width of the stair. " . . . . . To measure down the board, you need to consider the step being level at 7" down plus thickness of the tread = 1/2", but the run needs to be 11". The stringer isn't going to be at a 45 degree angle, so be careful to figure the tread being level. You'd have to do some algebra to figure the missing length along the stringer = OH AH OA the angle is going to be 90 degrees inside the cut and the rise is 7.5, the run is 11. Tangent = opposite angle divided by adjacent length. . . Ah heck, take 37/7.5x11 for 54.27 inches total length and use the stair calculator, lol. http://www.ez-stairs.com/widgets/stair_calculator/
Use a capenters level and mark off your rise run on it...7/11 is the tradional rise/run combo that feels natural to most people. Adjust the rise for what you need. Google the square layout for pics, or look in a 1-2-3 Home Depot book. Once you see it, you'll figure it out. It's pretty cool cutting your own stringers. Usually need a 2x10 or 2x12 board. Cut with a circluar saw, then finish with a hand/jig saw.
Ok I think i know what your saying, but for some reason I'm not sure what you all mean. 7 " down then 11" out for a stair? It's my first stringer cut myself. The pre done ones are not going to work. LOL wish I had taken pics, I assure you it was nothing short of a Benny Hill sketch.
you should contact Rich81Z.. he has sold stairs for a couple of decades.. he does the math in his head... accurately..lol he's a member here and a fanatic.. we are preparing to do the interior in his car.. been working on it for almost 10 yrs.
IF you can sketch out the setup with dimensions from deck to ground and tell me how far out they need to go I can sketch them up in AutoCAD in a couple minutes for ya. The 11 and 7 numbers dirt was mentioning come with the rule of 18 which basically means you want your run + rise = 18 or thereabouts. Lots of info here http://www.bestdecksite.com/introStairsPg1.htm