STAIRS CALCULATIONS - “RISER LIMITED” FUNCTION
Example: You are building a staircase that has a oor-to-oor measurement of 12 Feet 8 Inches, and a
run of 18 Feet 6 Inches. The building code you must follow mandates that risers can be no more than
7-1/2 Inches. Calculate the below stair values, and make sure that the riser height does not exceed the
stored Desired Riser Height of 7-1/2 Inches:
KEY INPUT & DISPLAY
0
2. Enter the rise and run measurements:
RISE 10
Feet
4
Inch
RUN 15
Feet
8
Inch
R-HT 7-5/16
Inch
3. Find Stair values using the “Riser Limited” function:
RSRS 17.
R+/- 0-5/16
Inch
T-WD 11-3/4
Inch
TRDS 16.
T+/- 0
Inch
OPEN 12
Feet
0-5/8
Inch
STRG 18
Feet
5-7/16
Inch
INCL 31.90˚
RUN 15
Feet
8
Inch
STORED
RISE 10
Feet
4
Inch
R-HT 7-1/2
Inch
T-WD 10
Inch
HDRM 6
Feet
8
Inch
FLOR 10
Inch
STORED
STORED
STORED
STORED
STORED
riser height
number of risers
riser underage/overage
tread width
number of treads
tread overage/underage
length of stairwell opening
stringer length
angle of incline.
1. Check that the Desired Riser Height is set to 7-1/2 Inches”
R-HT 7-1/2
Inch
STORED
Rcl
7
Page 28
Rise
Run
Inch
8
4
5
Inch
Stair
Stair
Stair
Stair
Stair
Stair
Stair
Stair
Stair
Stair
On/C On/C
1
0
Feet
1
Feet
Conv
(Riser Limited)
Stair
Stair
Stair
Stair
Stair