How to measure the total rise of a staircase

Every other number on a staircase comes from one measurement: the total rise. If it is wrong by half an inch, the riser height is wrong, the last step is wrong, and the stringers are cut wrong. This guide shows how to take the measurement properly, and how to handle floor finishes that are not installed yet.

What total rise is

Total rise is the vertical distance from the finished surface of the lower floor to the finished surface of the upper floor. It is not the height from subfloor to subfloor, and it is not measured along the slope of the stair.

For outdoor stairs, such as deck stairs, the lower end is the top of the landing, not the bare ground. See the deck stairs guide.

What you need

• A tape measure, long enough for the full height (or a laser distance meter).
• A 4 ft level, or a straight board with a level.
• A helper, if the rise is more than a few feet.
• A pencil and paper.

Step 1: find a reference line on the lower floor

Pick the spot where the bottom of the stair will land, and measure there. Floors are rarely perfectly level, so a reading taken a few feet away from the stair can be off by a quarter inch or more.

Step 2: bring the upper floor level down

1. Lay a straight board or a long level across the opening, resting on the upper floor and projecting out over the lower area.
2. Level it.
3. Measure straight down from the underside of the board to the lower floor.

For a long rise, a laser level or a plumb bob helps. What matters is that the measurement is truly vertical.

Step 3: correct for floor finishes

Often the finished floors are not installed yet, so you measure down to a subfloor or to the framing. Add and subtract the finish thicknesses you know will be installed.

• Upper floor finish (hardwood, tile, carpet with pad): it makes the upper floor higher, so the total rise increases by that thickness.
• Lower floor finish: it makes the lower floor higher, so the total rise decreases by that thickness.

Worked example

You measure 107 in from subfloor to subfloor. The upper floor will get 3/4 in hardwood, and the lower floor will get 3/8 in tile.

107 + 3/4 − 3/8 = 107 3/8 in

The total rise to use is 107 3/8 in (107.375 in).

Step 4: measure more than once

• Measure again from the other side of the opening.
• If two readings differ by more than 1/8 in, find out why before you go on. A common reason is a floor that slopes or a board that was not level.
• Write the number down along with the date and what it includes (for example “subfloor to subfloor, finishes added”).

Step 5: use the number

Divide the total rise by a riser height near 7 in and round to a whole number of risers. The stair calculator does this and checks the result against the IRC. The stringer guide then shows how to turn it into cuts.

Common mistakes

• Measuring along the slope instead of straight down.
• Forgetting the finishes, which is the most common cause of a last step that is too tall or too short.
• Measuring to the rough floor when the finished floor will be higher or lower by a significant amount.
• Measuring away from the landing point on sloping or uneven ground.
• Rounding too early. Keep fractions until you have divided by the number of risers.

Why this matters for code

The IRC allows a variation of no more than 3/8 in between the tallest and the shortest riser in a flight. A mistake in the total rise ends up in the first or last step, which is exactly where it makes a stair feel unsafe. The IRC requirements guide covers the limits.

Sources and further reading

• Trex Academy: how to calculate and cut stair stringers
• Fine Homebuilding: laying out the deck stair stringers
• This Old House: how to build deck stairs
• Knox County codes: residential stair requirements

This guide is general information, not engineering or legal advice. Building codes differ by location and edition, so confirm the rules with your local building department before you build.