Stair Riser Tread Ratio

Building stairs for your deck is often considered the most difficult part of the construction project.

Stair riser tread ratio.

The r r then was 16 too low and 2r r was 28 too high. Step tread 2 riser 26 or 27. 7 riser height tread depth y 0 7535 37 slope. Having the right calculations before getting started can make the task a lot easier.

You ll find the tread width in the column on the left and the rise height in the column on the right. A riser higher than 7 inches is not recommended outside though interior stair dimensions can be higher than that. Rise r 12 run r 4 r r 16 too low 2r r 28 too high won t be comfortable. The optimum riser for exterior stairs is 6 1 2 inches making the tread 13 inches wide.

Typically a single 2x12 or two 2x6s are used for stair tread material. Handrail height to be placed a minimum 34 inches to 38 inches. The ratio for exterior stairs is two risers the tread 26 inches. Stairs with solid risers and 2x12 treads.

Treads the tread depth b should not be less than 10 inches 254 mm. We would need change the stair tread depth to make a 37 slope stair that has an acceptable 7 inch riser height. Building codes generally suggest that the minimum length of a tread be 10 inches 25 4 cm. Fortunately the stair is used primarily for storage.

It is not the physical height of the riser because this excludes the thickness of the tread. In a given run of stairs the greatest tread depth should not exceed the smallest by more than 3 8 inch 9 5 mm. Or use the handy chart below with the ratios already figured for you. The rise or height of a step is measured from the top of one tread to the top of the next tread.

Staircase calculation formula is total required number of risers total stair rise height of one rise 60 6 10 riser total required number of tread total stair tread or run width of one tread 90 10 9 tread. At stair riser specifications and at stair dimensions width height you ll read that stair risers should be 7 inches 178 mm maximum and 4 inches 102 mm minimum. Handrail graspability to be either type i or ii with a minimum 1 1 2 inch clearance from a wall. Maximum 7 3 4 inch stair riser height.