Chapter 18 Stair Construction
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18.11 Open Stairs
Stairs that are open on one or both sides
require some type of decorative enclosure and
support for a handrail. Typical designs consist
of an assembly of parts called a balustrade,
Figure 18-25. The principal members of a balus-
trade are newels, balusters, and rails. They are
usually made in a factory and assembled on the
job by the carpenter.
The starting newel must be securely
anchored either to the starter step or carried
down through the fl oor and attached to a fl oor
joist. Balusters are joined to the stair treads
using either a round or square mortise. Two or
three may be mounted on each tread.
Working Knowledge
The main purpose of balusters is to prevent
anyone, children especially, from slipping under
the railings and falling to the fl oor below. Codes
usually require baluster spacing of no more than
6″, although 4″ is required in some localities.
18.12 Using Stock Stair
Parts
While many parts of a main staircase could
be cut and shaped on the job, the usual practice
is to use factory-made parts. These are avail-
able in a wide range of stock sizes and can be
selected to fi ll requirements for most standard
stair designs. See Figures 18-26 and 18-27. Stair
parts are ordered through lumber and millwork
Balustrade: An assembly with a railing resting on a
series of balusters that, in turn, rest on a base, usually
the treads.
Newel: The main post at the start of a stair and the
stiffening post at the landing.
Baluster: The vertical member (spindle) supporting
the handrail on open stairs.
Half newel
Handrail
Baluster
Newel post
Tread
Shoerail
Riser
Nosing
Handrail
Baluster
Newel post
Rosette
Stringer
Tread
Riser
Nosing
Stringer
Figure 18-25. Parts of an open stair. An assembly including a newel, balusters, and rail is called a balustrade.