The staircase is one of the most important components of a building. It helps people to access different floors of a building. When it comes to constructing a staircase, it is always important that you correctly calculate the slope of the flight to ensure that it isn’t too steep. The calculation of staircase slope is very simple and easy. You just need to know the width of tread and height of the riser. After calculating, you will come to know whether the stair slope is legal or not.
Step 1
Measure the distance of treads (Exclude the width of nosing). If all the treads are uniform in size, measure one tread otherwise you will need to measure all treads.
Let the width of tread = 250 mm.
Step 2
Measure the height of risers. If risers are all uniform in size measure only one. If they are different sizes you will need to measure all risers.
Let the height of riser = 150 mm.
Step 3
Divide the riser height by the tread width and then calculate the inverse tangent.
tanθ = Riser Height/Tread Width = 150/250 = 0.6
∴ θ = tan−1 0.6 = 31°
Keep in mind that tread and riser of uniform size ensure easy measurements and more accurate results. I advise you to build a staircase that it’s the slope is not too steep or steep enough (Staircase slope between 30° to 40° is considered as standard).
For more information watch this video