Inputs
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Advanced
Cap & Band adds extra wrap per step.
If >0, total length rounds up to nearest repeat.
Results
Total runner length
0.00 ft
Metric
0.000 m
Pre-rounding subtotal
0.00 in
Rounded by pattern
0.00 in
Estimated area
0.00 sq ft
Metric
0.000 m²
Example data
Click “Load” to populate inputs with a scenario.
| Name | Steps | Riser | Tread | Method | Layout | Landing(s) | Load |
|---|---|---|---|---|---|---|---|
| Classic straight | 13 | 7.5 | 10 | waterfall | straight | 36 / 0 | |
| Turned with landing | 6 + 7 | 7 | 10 | capband | lshape | 40 / 0 | |
| Winders + U shape | 10 + 4 winders | 7.75 | 10.5 | waterfall | ushape | 36 / 36 |
Formula used
This tool estimates runner length along the walking line for common installations.
L_step = R + T + k·W
where R = riser height
T = tread depth
W = nosing wrap allowance
k = 1 for Waterfall, 2 for Cap&Band
L_winder = R + G + k·W
where G = average winder going (centerline)
Subtotal (in) =
L_step × N_regular + L_winder × N_winders
+ Landing_1 + Landing_2 + Extra_flats
+ Top_tuck + Bottom_tuck
Apply waste:
Subtotal_waste = Subtotal × (1 + Waste%/100)
Pattern rounding (optional):
If Repeat > 0 then
Total_rounded = ceil(Subtotal_waste / Repeat) × Repeat
else
Total_rounded = Subtotal_waste
Convert:
Feet = Total_rounded / 12
Meters = Total_rounded × 0.0254
Area (if width given):
Sq_ft = Feet × (Width_in / 12)
Sq_m = Meters × (Width_in × 0.0254)Assumes typical residential geometry. For specialty nosings, bullnose returns, or complex winders, measure on site and override inputs accordingly.
How to use this calculator
- Choose your measurement system. All subsequent inputs use those units.
- Select the installation method: Waterfall or Cap & Band.
- Enter counts for regular steps and winders, plus the average winder going if any.
- Enter riser height, tread depth, and the nosing wrap allowance.
- Add landing depths (walking direction), any other flat runs, and top/bottom tuck allowances.
- Optionally set a pattern repeat to force rounding and a waste percentage.
- Click Calculate. Export results to CSV or PDF for records or quoting.
FAQs
Yes. Waterfall uses one wrap allowance per step. Cap & Band wraps under the nosing and typically consumes roughly two wrap allowances per step.
Measure the distance along the walking line that the runner covers on the landing, not the full width. Add each landing once in the inputs.
Increase the nosing wrap allowance to match the extra coverage needed, or add to the waste percentage to protect against under-ordering.
When a repeat length is provided, total length is rounded up to the nearest multiple. Always confirm repeat orientation and match before cutting.
Yes. Provide a runner width and the tool will compute approximate square footage and square meters from the final rounded length.
The waste percentage covers typical trimming and on-site adjustments. Increase it for complex layouts, bold patterns, or if you are unsure.
Enter counts and landings for the portion you are covering and set others to zero. Top and bottom tucks can still be included as needed.