Measuring for a waterfall installation

Waterfall is the simpler of the two classic installation styles: the runner runs off the front of the tread and falls straight down to meet the next tread, without being pushed into the corner behind the nosing.

It uses slightly less material than Hollywood, installs faster, and suits thicker or stiffer runners such as sisal.

Your staircase

Optional starting measurements

Example measurements only, not building-code advice. Replace them with measurements from your own stairs.

Check a few steps before using one set of measurements for the whole flight.

Number of stairs

Count the tread-and-riser pairs the runner will cover. Exclude landings.

Tread depth (in)

Measure the runner path across the flat tread. Fractions like 10 1/2 work.

Riser height (in)

The vertical face between two treads.

Waste allowance

Custom%

10% is the starting allowance here, not a guarantee. Ask your fitter about patterns and turns.

Add a nosing / overhang allowance per step

Enter the extra runner path around the edge, including any underside wrap. Do not add it twice if it is already included in your measurements.

Your runner estimate

20 ft 3.1 in

Total runner required for 13 steps, including a 10% waste allowance.

Total runner length in each unit
Inches	243.1 in
Feet	20.26 ft
Feet & inches	20 ft 3.1 in
Yards	6.75 yd
Meters	6.17 m
Centimeters	617.47 cm

Length to order

21 ft

7 yd · 6.4 m · 252 in

This calculator provides an estimate based on the measurements and installation assumptions you enter. Complex, curved or winder staircases may require professional measurement.

One step, shown in profile

Side elevation of a staircase. The runner travels across each tread and down each riser, so every step consumes tread depth plus riser height of material.

Length for waterfall style

Waterfall length is close to steps × (tread + riser), with only a small allowance over the nosing itself — typically 0.5 to 1 in per step depending on how pronounced the bullnose is.

Waterfall versus Hollywood on material

Hollywood pushes the runner into the back corner of every step, adding roughly 1 to 2 in per step. Across 15 steps that is up to 30 in — over two feet of extra runner.

When waterfall is the right choice

Choose waterfall for thick, stiff or heavily textured runners, for a more casual look, and where the nosing profile is square rather than deeply rounded.

Questions people ask

Does waterfall installation use less runner?: Slightly, yes — about 1 to 2 inches less per step than Hollywood, because the runner is not pushed into the corner behind each nosing.
Which style is better for sisal?: Waterfall. Stiff natural fibres do not tuck neatly into the riser corner and can crease if forced.

Related guides

See all stair runner calculator guides