Stair Wainscoting Calculator

Divide the sloped band into whole panels

On a straight stair wall, rails follow the slope while framed-panel stiles stay vertical. That creates parallelogram openings. Compare the horizontal projected clear width when choosing a count and read the separate sloped edge lengths when planning cuts.

Use the flight’s measured endpoints and its own zero. Lower and upper landings are horizontal segments with their own references. A drawing can show them together without turning all of their measurements into one tape coordinate around the room.

Measure rise, run, and band from named references

Measure total vertical rise and horizontal run between the same endpoints. Alternatively, use a unit riser/tread pair with a separately measured span, or a measured angle with a horizontal run or slope length. Choose one authoritative slope source rather than mixing conflicting measurements.

Record whether the decorative band height is vertical or perpendicular to the slope. Measure actual rail and stile faces, and record any separate landing spans. The measured band reference and the physical floor line are not automatically interchangeable.

Keep slope length and projection distinct

The decorative slope comes from rise and horizontal run. The slope length is the diagonal between the same endpoints. A sloped rail’s face is measured perpendicular to the rail, so its vertical projection changes with pitch.

Choose framed panels or picture-frame molding

Framed panels use vertical stiles between raking rails. In picture-frame mode, separate molding pieces follow the sloped frame edges and meet at acute and obtuse corners. Their outside, inside, and blank dimensions answer different cutting questions.

For a vertical band, the rail faces’ vertical projections reduce the clear stile space. If you choose a perpendicular band reference, read the corresponding result rather than reusing a vertical-height subtraction.

Compare count across the flight and landings

A target projected width produces feasible whole-count candidates. Compare their actual clear widths and the number of pieces, then select a count you want to keep. More divisions make narrower fields; fewer divisions leave wider ones.

The consistent option compares candidate widths across the flight and enabled landings. Read its spread together with the deviation from your target. A more uniform rhythm can be farther from the target and is not automatically the preferred design.

Inspect landing joints at the actual rail edges

A horizontal landing rail meeting a raking rail creates a knee transition. Inspect the joint and each adjoining finished edge in the drawing; the projected segment length is not necessarily the longest manufacturing length needed to cut the transition.

A turn onto a non-coplanar wall requires a separate scene and a resolved physical connection. Do not infer an unseen compound corner from a flat elevation of the flight and landing.

Read the angle reference before setting the saw

An internal corner angle describes the opening between members. An end-cut angle describes the selected deviation from square in its stated plane. Neither should be copied to a saw dial without checking the piece face, fence orientation, and whether a jig changes that reference.

Keep finished edge length, long point, short point, and manufacturing blank distinct in the schedule. A parallelogram piece can require a longer blank than either finished long edge. Test a real sample corner before cutting repeated material.