1 Presentation 37: STAIRWELL LENGTH AND HEADROOM

2 Stairwell Length and Headroom A stairwell is the opening in a floor through which stairs are used. Its length depends on the unit rise and unit run of the stairs. Sufficient headroom must be maintained along the entire stair.

3 Stairwell Length and Headroom Stairwell length Headroom Unit Rise Unit Run Headroom must be more than 6′- 8″ (80″). The stairwell length is adjusted to maintain headroom.

4 Stairwell Length Gentle stairs need a longer stairwell length to allow for the headroom. Stairwell length

5 Stairwell Length Stairwell length How many unit runs under the opening?

6 Stairwell Length Stairwell length How many unit runs under the opening? This number depends on the number of rises under the opening.

7 Headroom Number of rises is related to the desired headroom. Headroom

8 Number of rises is related to the desired headroom. Upper Construction Headroom Note where the headroom is measured to on top. Upper construction must be included with the headroom.

9 Stairwell Length Procedure 1.Add desired headroom to upper construction measurement. 2.Divide this number by the unit rise and round up. (This is # of unit runs). 3.Multiply this number by unit run.

10 Stairwell Length Calculation Determine stairwell length if: 12 ½″ 10 ½″ 7 ½″ 80″ Unit rise = 7 ½″ Unit run = 10 ½″ Headroom = 80″ Upper const. = 12 ½″

11 Calculation Add headroom to upper construction ½″ = 92 ½″ total clearance Divide by unit rise and round up. 92 ½″ ÷ 7 ½″ = → 13 rises Multiply by unit run. 13 x 10 ½″ = 136 ½″ Stairwell Length.

12 Stairwell Length Calculation Stairwell length should be 136 ½″. 7 ½″ 10 ½″ 12 ½″ 80″ 136 ½″

13 Conclusions Headroom is typically more than 80″. Stairwell length is determined from headroom, upper construction thickness, unit rise, and unit run.