Here's instructions for your brain. http://www.mathsisfun.com/algebra/trig-solving-triangles.html

If you want to solve the probelm with your wallet, purchase an angle finder at Home Depot for <$9.

 

e.g, Rise @ 170mm
e.g, thread @ 280mm

170 (rise) divided by 280 (thread) = 0.607142..... (2nd function TAN) = 31.26 °

 

I used to get in rip roaring fights with my old boss over about stair layout. Rise/ tread depth only works as long as there isn't a stair nosing involved that goes past the riser on the lower step. Fairly typical on wood steps and steps that have a brick or stone tread. He could never seem to grasp that concept and any time he did layout, his steps always ended up with the treads being deeper by the depth of the overhang and running out farther by the accumulated nosings ( 10 treads @ 1.5" adds 15 " to the total run, a big deal if you are working between two fixed points horizontally.)


I'd always work "tread" as the distance between risers and ignore the nosing so my math would work right. So if the total tread size was 12" and we had a 1 1/2" nosing that over hung the riser, I'd use 10 1/2" in my calculations for distance and it would work just fine.

 

I'd always work "tread" as the distance between risers and ignore the nosing so my math would work right. So if the total tread size was 12" and we had a 1 1/2" nosing that over hung the riser, I'd use 10 1/2" in my calculations for distance and it would work just fine.

You were right. The tread is the exposed area vertically below the nosing. The area under the nosing is not involved in the equation.

 

Get a level from Home Depot. I use the torpedo. Get a straight edge and run it across the steps and the place level on top.

I always take the pitch, rise over run of each steps. Measure vertical and horizontal with a level. I would not calculate the pitch from just one step for the entire run. The longer your run the more your error will be emphasized.

I use trig to compare angles and find spacing for balusters, too.

While ideally it would work, I don't like shooting vertical and horizontal the length of the entire step since it cannot be done in every case.

I also have a some type roofing angle finder or wood working protractor for transferring data to my table. Sweet cheap find even though I don't know what it is.

 

Here's a site that does most of the layout for you http://tinyurl.com/lh4tj4z ....Mike

 

get a consruction master 4 calculater ... run rise,,,, tells u everything

 

if all you're doing is a handrail get a 8' smart level and average between several stairs. probably somewhere around 32.5 deg

 

Use a bevel gauge and a Level. Set the level plumb. on the stringer, and use the bevel gauge, or a protractor for that mater,to get the angle. You can also make parallelogram with flat bar and wing nut is the corner. Set the parallelogram on the stringer, make the vertical legs plumb, tighten the wing nuts and you have a reasonably good approximation of angle.

brad

 

Commercial stair codes (in Ca) are different than residential, so the angle could change. There is also no code on the depth of tread as long as they are equal, so that would affect the angle too. Construction master calculator does it well, which is also available as a smart phone app. It works well but is the same price as the calculator.

 

Commercial stair codes (in Ca) are different than residential, so the angle could change. There is also no code on the depth of tread as long as they are equal, so that would affect the angle too

Define depth of tread, you lost me

 

I've never worried about the angle. Carefully calculate the rise from finished floors foot to head, (this may be different from a simple measurement as one floor may not be level), divide by 7.5 inches, round up to whole numbers. Divide rise by the new whole number.This is your rise. you will have one more riser than tread as the floor top and bottom take their place.
Calculate run bottom to top. Again something may not be plumb, do your measuring level. Using the number of risers minus one divide total run this is tread length. If space is adequate, risers should be less than 7.5" Run NOT less than 10". 2 x rise + run works well at 25 the average human stride. Check local codes, and comply! Use brass stops on your framing square to lay out stringers, adjust top and bottom of stringers to allow for thickness of treads and risers so each step is equal. Subtracting from bottom riser, don,t forget the thickness of top riser. Treads should overhang risers to form a rounded nosing, as should the finish floor at top.
If the stairs are to be metal, use a board to make a pattern you can try in the opening to check yourself.
If you seem to be running out of length, a common problem you can cheat allowing the bottom treads to extend beyond the line vertical from the ceiling opening, but be sure to allow plenty of head room as one nears the bottom of the stairs. No one wants a head knocker!

 

You know that little book that comes with every speed square?
Yah, that one.

I've laid out whole houses with that puppy!

 

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