How to calculate and cut stair stringers

welcome to sawdust and wood today today I'm going to teach you how to cut a stair stringer how to take a measurement and cut it and lay it out of the framing square we are going to do 28 inches today let's get started this is our example for today I need to rise 28 inches and on these steps for that so the math is 28 inches divided by seven because between seven to eight inches is normally code for the rise four steps so 28 divided by 7 equals four steps then you take 28 and you divide it by the four steps and that gives me seven so I need four steps the rise seven inches and the run is normally 10 inches on steps and I have it drawn out here so we can look at it and I even had the kick or shown at the bottom that you're gonna see later on in the video it's a 2 by 4 kicker so seven inches arise and 10 inches of run so I'm gonna set the blade of my frame is square to 10 on the edge of the board and the tongue to 7/10 being the run and 7 being the rise so I'm gonna trace that then I'm going to extend my square on the line of the 10 and trace it through that's gonna represent the floor where the stairs are gonna meet the floor then I'm gonna go ten and seven again and trace Ted and that is gonna be our second step then with 10 and seven again I'm gonna line 10 up with the line and seven over here I measure the board and trace that and I want to write three for our third step my 10 and 7 up again I'm gonna trace that so I'm going to extend this line all the way through is that stand of our stairs so when I made my first mark I let I'm more completely across and that is the floor once you start to visualize your stairs on the stringers can be really easy to check your layout so seven inches up on the square that was the first mark so that's our first step up ten inches of rung all right step one step two seven inches up ten inches over step three seven inches up ten inches over so that brings us to 21 inches up right now on this strand and we go on for 28 now most steps you don't cut that last stringer because your step with your top step on the string would be right at the top of whatever you were building up to 28 inches so I'm going to stop my step right here at 21 and then the next step will be on the top of the platform that you'll be going up to and this is exactly what I mean my last step was in there and they would be another seven inch rise and that would put us perfect on the top of the deck that we were building up to so 7 14 21 we're gonna cut it across I'm gonna cut this out and I'm gonna show you what I'm talking about here I'm cutting the stair stringer and I had my wife come outside and film me so that's why I am rushing through cutting I should have had this board brace better I should have had on some saw horses and if I didn't have anybody to hold the board down I should have had a clamp down but I just didn't have the time to do it I wanted y'all to see me cutting it so I'm cutting each step out and you'll notice I do over cut in every step now if I were cutting these steps for somebody somebody's house I would stop my saw before it got all the way through and used a handsaw and finished the cut so it wouldn't have that over cut look also I want to note this is a 2 by 10 that I had left over for the last table I built and stairs are always cut on two by twelves so I just wanted to know that I didn't say it early in the video and I want everybody be very aware of that this was just some extra lumber I had and I figured I could do a video with it so here I am cutting the last step off square here's my staff stringer I have cut and the seven inches arrived and 10 inches of run and I'm gonna use a 1 by for my steps to deck the top which is 3/4 of inch stick so I have to deduct 3/4 of an inch off the bottom step so all the other steps line out right so I have it marked and I'm gonna make that cut all right so I took a scrap piece of 2x4 trace it off from Ikea and this is how the kicker fits into the bottom of the stairs stringer it holds everything in place at the bottom we're gonna cut that out right here and then on the ground level you have a 2x4 running the whole length of your stairs they call that accurate kick your cutout just trace the 2x4 scraps so on the stairs on the ground like this that 2x4 can sit right there and you can secure the bottom of your stairs like that here is a picture of your stairs stringer as it would look 7 14 21 and then whatever level you were going through the top of the deck or something would be right here and this is what I mean this is exactly how it would look when you nailed it up it would be one step short and everything would line up perfectly once it was put up that's all there is to it please comment any questions below thanks for watching now this is just an example let's say we had 27 inches total height would be 27 divided by 7 would equal 3.85 we'd round up the four steps twenty-seven divided by four steps would equal six point seven five which is six and three quarters advantage so we have four steps X 6 and 3/4 rise and 10-inch run and here is how we would look when you would lay it out to cut I just want to give another example [Music]

Channel: Sawdust and Wood

Views: 410,540

Keywords: stairs, stair stringers

Id: CyKvM-I76UI

Length: 7min 55sec (475 seconds)

Published: Sun Dec 03 2017