Question 1

What is a mortised stringer staircase?

Accepted Answer

In a mortised stringer staircase the treads sit in grooves milled (“mortised”) into the side wooden stringers. The treads thereby disappear into the stringer at the side — the staircase looks closed and calm. It is the classic construction and suits rather calm, traditional stairwells. We build it in all six woods and every flight form.

Question 2

When should I choose an open-string staircase?

Accepted Answer

In the open-string staircase — the stringer is also called a stringer beam — the treads rest on top of sawn-out seats. The tread ends stay visible, the staircase looks more open and lighter and lets more light through. This variant suits modern, open living concepts particularly well. Which stringer type fits your room we discuss using samples.

Question 3

Which flight form fits which stairwell?

Accepted Answer

The flight form follows your floor plan, not the construction type — every stringer staircase can be built straight, quarter- or half-turn, as a landing, Z- or U-shape staircase. A straight staircase needs a long, narrow run; turned forms or an intermediate landing save space and adapt to tight or angular stairwells. Because we manufacture ourselves there are no production-related restrictions — we align the flight form to your measurement.

Question 4

How many stringers does a stringer staircase have?

Accepted Answer

That depends on the flight form. A straight stringer staircase usually has two stringers — left and right. In turned flights several stringer sections come together depending on the path: starting stringer, one or more intermediate stringers and a landing stringer. We plan the stringers so they suit the floor plan and the desired look.

Question 5

Which woods and surfaces are available for the stringer staircase?

Accepted Answer

You choose from six woods: oak, knotty oak, beech, beech heartwood, ash or hevea. As a surface there is oiled with hard wax oil, clear-lacquered or white-lacquered. You may freely combine treads, stringers and risers — for example oak treads on white-lacquered stringers. Because we manufacture in our own workshop in Witten, this material mix is the norm with us.

Feature	Mortised stringer	Open-string (stringer beam)
Tread support	Treads sit in grooves milled into the stringer	Treads rest on top of sawn-out seats
Look	Closed and calm — treads disappear into the stringer at the side	More open and lighter — tread ends stay visible
Effect in the room	Looks more solid, frames the flight at the side	Looks slimmer, lets more light through the treads
Typical choice	Classic, rather calm stairwell	Modern, open living concept
Flight forms	All — straight to turned	All — straight to turned
Woods and surfaces	All six woods, oiled, clear-lacquered or white-lacquered	All six woods, oiled, clear-lacquered or white-lacquered

Feature	Mortised stringer	Open-string (stringer beam)
Tread support	Treads sit in grooves milled into the stringer	Treads rest on top of sawn-out seats
Look	Closed and calm — treads disappear into the stringer at the side	More open and lighter — tread ends stay visible
Effect in the room	Looks more solid, frames the flight at the side	Looks slimmer, lets more light through the treads
Typical choice	Classic, rather calm stairwell	Modern, open living concept
Flight forms	All — straight to turned	All — straight to turned
Woods and surfaces	All six woods, oiled, clear-lacquered or white-lacquered	All six woods, oiled, clear-lacquered or white-lacquered

Stringer staircases

Mortised or open-string — and every flight form

Mortised versus open-string — the two stringer types compared

Project examples

Frequently asked questions

Related and helpful

Related services

In the glossary

From the pillar

Your stringer staircase — mortised or open-string, made in Witten