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Week 8
Stairs and Fireplaces
Objectives
• This chapter discusses stairs and
fireplaces: types, sizes, code
requirements, design considerations, and
how to draw them
• Residential applications are the primary
focus of this chapter
Stairs
• Form of vertical access
• Stairs may be open, partially enclosed or
contained in a well
• May be residential, commercial, indoor,
outdoor, built on site, or prefabricated
• May be constructed of wood, concrete or
metal
• All stairs share some common features
and must meet local code and accessibility
requirements
Stair Features
• Balustrade: assembly containing the
balusters, newel posts and handrail
• Wall rail: handrail that is mounted on a wall
and supported by wall-mounted brackets
instead of newels
• Headroom: clear vertical distance between
the tread and the ceiling, measured
linearly along a sloped plane
• Pitch: angle of the staircase; the rise
divided by the run
Stair Features (cont’d.)
Figure 11.6 Residential
staircase clearances and
dimensions.
Stair Features (cont’d.)
• Rise: vertical distance
• Run: horizontal distance
• Stairs, stairway, staircase, stairwell, flight:
a series of steps or flights of steps used for
passing from one floor or landing to
another
• Landing: level rest area on a staircase
• Stringer: diagonal structural support for the
steps
Stair Features (cont’d.)
• Step: consists of riser and tread
• Riser: vertical board at the front of the step
• Tread: horizontal board at the top of the
step
• Well opening: hole made in an upper floor
for stairway placement
• Handrails and guards: help people steady
themselves and usually consist of a single
rail installed at a specified height
Stair Features (cont’d.)
Figure 11.11 Step construction detail.
Non-Residential vs.
Residential Code
Compliance
• Handrails on residence landings must be
between 34" –38" high, measured from
tread top to handrail top
• Handrails on commercial building landings
must be a maximum of 42" high.
• Stairs must be at least 36" wide in
residences and 44" wide in commercial
buildings with occupancy over 50
Stair Types
• Straight run stairs: have no turns but may
have a landing
• L-shaped stairs: have a landing and a turn
– Used when there is not enough space for a
straight-run
• Winder stair: L stair where the L-shaped
turn is made with trapezoidal treads due to
lack of space for a landing
• U-shaped or scissors stair: consists of two
parallel flights
Stair Types (cont’d.)
Figure 11.18 Winder stairs.
Stair Types (cont’d.)
• Spiral stair: rises in a circle above a center
point; used where there is little horizontal
space available
• Circular stair: requires a lot of horizontal
space
– Steps are trapezoidal and rise along an
irregular curve or arc
Exterior Stairs
• Designed with smaller riser heights and
wider treads than interior stairs
• There should be a landing every 16 risers
on continuous stairs
• Usually the same material used on the
deck or porch is used for treads, and a
non-skid material can be used to cover
them
Exterior Stairs (cont’d.)
Figure 11.31 Concrete, wood,
and open-riser exterior stairs.
Basement and exterior wood steps
rarely require risers.
Stair Design
• Consider the staircase’s potential use
when deciding how wide to make it
• Minimum code requirements result in
steep, narrow stairs
• Use several short landings
• Avoid single steps to sunken rooms
• Select handrails that complement the
staircase
• A well-designed staircase follows given
formulae
Calculating How Many
Stairs Are Needed
• Formulae
–
–
–
–
Two risers plus 1 tread = 24"–25"
Riser tread = 72"–77"
Riser tread = 17"–18"
Angle should be 30°–37°
• Know the total rise
• Calculate the height and number of risers
• Calculate the width and number of treads
Creating a Grid to
Draw the Stairs
• Draw a rectangle, making the length the
total run available and the height the total
rise
• Divide one of the vertical lines into the
number of risers needed
• Mark off all 19 increments and project
these increments horizontally to the
vertical lines
Creating a Grid to Draw
the Stairs (cont’d.)
• Now divide one of the horizontal lines into
the number of treads needed
• Mark off all 18 increments and project
these increments vertically to the
horizontal lines
• Darken the risers and treads
Creating a Grid to Draw
the Stairs (cont’d.)
Figure 11.38 Drawing a stairs grid: step 6.
Ramps
• Sloped surface whose purpose is to make
a building accessible
• Landings are required at the top and
bottom, and their length must take into
account any adjacent doors
• An entry platform should extend 18"
beyond the handle side of the door to
facilitate wheelchair use
• Any ramp that exceeds a 1:12 ratio must
have at least one handrail
Fireplaces and Stoves
• Framed opening in a chimney that holds
an open fire
• A stove is a free-standing external
fireplace in a metal container
• All fireplaces share some common
features and must adhere to building
codes for proper build and installation
Fireplaces and Stoves
(cont’d.)
Figure 11.50 Different fireplace styles.
Features
• Chimney: vertical structure that carries
smoke and gas out of the room
• Header: horizontal component over the
fireplace opening
• Firebox: combustion chamber where the
fire is contained
• Firebrick: heat-tempered brick
• Surround: immediate border of the face
around the firebox opening or a noncombustible/masonry decorative frame
Features (cont’d.)
• Opening: rectangular recess in the
surround
• Hearth: floor of the fireplace.
• Mantel: whole frame surrounding a
fireplace
• Vent: opening that draws air into the fire
and allows combustion byproducts to
escape
Fireplace Styles
• Site-built: built on a masonry foundation
and is usually rectangular with one, two, or
three open faces
• Prefabricated: has a metal shell and a
brick-lined firebox and is insulated
• Insert: heating unit that fits inside existing
fireplace to convert it into an efficient zone
heater
Fireplace Styles
(cont’d.)
Figure 11.58 Two-face
opposite masonry
fireplace.
Design Considerations
• Purpose: to provide an aesthetic focal
point, a zone heater, or both
• Placement: fireplace can occupy an
interior wall, an exterior wall, or a corner
• Firebox opening size: important for
appearance and operation
• Available fuel options: cordwood, wood
pellets, fire logs, natural gas, propane, oil,
coal, and electricity
Summary
• Stairs and fireplaces are important building
components
• Many styles and materials for each are
available
• When choosing and placing them, you
must consider technical considerations and
building codes along with aesthetic,
functional, and design criteria