Building Stairs

Category Construction Glossary
Stair Parts

Tread - The part of the stairway that is stepped on.
It is constructed to the same specifications
(thickness) as any other flooring. The tread "width"
is measured from the outer edge of the step to the
vertical "riser" between steps.
Riser - The vertical portion between each tread on
the stair. This may be missing for an "open" stair
Nosing - An edge part of the tread that protrudes
over the riser beneath. If it is present, this means
that horizontally, the total "run" length of the stairs is
not simply the sum of the tread lengths, the treads
actually overlap each other slightly
Starting step - Where stairs are open on one or
both sides, the first step above the lower floor may
be wider than the other steps and rounded. The
balusters typically form a semi-circle around the
circumference of the rounded portion and the
handrail has a horizontal spiral called a "volute" that
supports the top of the balusters. Besides the
cosmetic appeal, starting steps allow the balusters
to form a wider, more stable base for the end of the
handrail. Handrails that simply end at a post at the
foot of the stairs can be less sturdy, even with a
thick post. A double bullnose can be used when
both sides of the stairs are open.
Winders - Winders are steps that are narrower on
one side than the other. They are used to change
the direction of the stairs without landings. A series
of winders form a circular or spiral stairway. When
three steps are used to turn a 90° corner, the
middle step is called a kite winder as a kite-shaped
Stringer, stringer board or sometimes just string -
The structural member that supports the treads and
risers. There are typically two stringers, one on
either side of the stairs; though the treads may be
supported many other ways. The stringers are
sometimes notched so that the risers and treads fit
into them. Stringers on open-sided stairs are often
open themselves so that the treads are visible from
the side. Such stringers are called "cut" stringers.
Stringers on a closed side of the stairs are closed,
with the support for the treads routed into the
Trim - Trim (e.g. quarter-round or baseboard trim)
is normally applied where walls meet floors and
often underneath treads to hide the reveal where
the tread and riser meet. Shoe moulding may be
used between where the lower floor and the first
riser meet. Trimming a starting step is a special
challenge as the last riser above the lower floor is
rounded. Today, special flexible, plastic trim is
available for this purpose, however wooden
mouldings are still used and are either cut from a
single piece of rounded wood, or bent with
Straight Stairs
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