Calculate Riser Height (Option 1)

What happens in this clip

Take the total rise (35 inches) and divide it by a whole number slightly higher than your approximate riser count (e.g., 5, since 4.66666 is closest to 5 when rounding up). In this example, 35 inches divided by 5 risers equals 7 inches per riser. A riser height of 7 inches is considered acceptable, typically falling within the comfortable range of 7 to 8 inches, and ideally between 7.25 and 7.75 inches for optimal comfort. This calculation determines a possible, comfortable, and potentially code-compliant individual riser height.

Goal: Find a comfortable and potentially code-compliant individual riser height

What's used

Tools

• Calculator

About the full video

This instructional guide details the process of accurately calculating the number and individual height of stair risers, ensuring they meet building codes for safety and comfort. The method involves measuring the total vertical rise, estimating the number of risers using an average height, and then testing different whole numbers of risers against the total rise to determine compliant and comfortable individual riser heights.

Step 4 of 7: Recalculate Actual Riser Height

Divide the total rise by the number of risers calculated in Step 3. This will give you the actual height for each riser. For example, if the total rise is 100 inches and you have 14 risers, the actual riser height is 100 / 14 = 7.14 inches.

Open this step in the guide

Every video in How to Calculate How Many Stairs You Need

1. Step 1: Measure the Total Rise

   • 0:15–0:29 Measure Total Rise
   • 0:01–0:28 Measure Total Vertical Rise
   • 0:17–0:31 Measure Total Rise

2. Step 2: Determine the Ideal Riser Height

   • 1:03–1:44 Calculate Riser Height (Option 1)
   • 1:44–2:33 Calculate Riser Height (Option 2) and Verify Code Compliance
   • 4:32–5:10 Calculate Individual Riser Height

3. Step 3: Calculate the Number of Risers

   • 0:32–0:54 Calculate Number of Risers
   • 8:59–9:54 Calculate Number of Risers and Treads
   • 7:42–8:55 Calculate Number of Risers

4. Step 4: Recalculate Actual Riser Height

   • 1:03–1:44 Calculate Riser Height (Option 1) (this video)
   • 4:32–5:10 Calculate Individual Riser Height
   • 1:44–2:33 Calculate Riser Height (Option 2) and Verify Code Compliance

5. Step 5: Calculate the Number of Treads

   • 3:54–5:04 Calculate the Number of Treads and Understand the Logic
   • 0:54–1:13 Determine Number of Treads
   • 8:59–9:54 Calculate Number of Risers and Treads

6. Step 6: Determine the Total Run

   • 1:13–1:29 Calculate Total Run
   • 1:31–2:57 Calculate Unit Run and Total Run
   • 6:51–8:30 Calculate Total Run

7. Step 7: Calculate Tread Depth

   • 2:05–2:24 Calculate Individual Riser Height & Tread Depth
   • 9:54–10:28 Determine Tread Run and Total Run
   • 8:50–10:30 Calculate Risers, Treads, and Total Run