lecture 9 Flashcards
tread
horizontal surface of a stair that we walk on
riser
vertical component of a stair that separates one tread from another
what is nosing
the front edge of a tread that overhands the riser
whereare railings required?
required on both sides of the stairs
when do you need a landing with stairs?
if our stairs change direction and every 12’
what are the key elements of a stair
tread
riser
nosing
railings
landings
what is the ratio of rise to run in a typical stair
(2) risers + (1) tread= 24” to 25”
6 1/2” -7” risers and 11” treads are very commonly used in REZ construction
tread depth
10” min for rez
11” min for commercial
riser height
between 4”-7 3/4” for rez
between 4-7” for commercial
nosing overhang
is between 3/4- 1 1/4” for rez
minimum stair width
36” in a single family rez
44” everywhere else
what is the max rise of a stair before the landing is required?
12’
what is the mim head clearance between a tread and the projection of a tread
80”
6’8”
landing must be how wide
at least the width of the stairs
striaght run stair
a stair that extends from one level to another without turns or winders
how can a stair be turned?
quarter-turn stairs
half-turn stairs
winding stairs
quarter-turn stairs
a stair that turns 90 degrees or that is L-shaped plan
half-turn stairs
a stair that turns 180 degrees or that is U-shaped in plan
winding stair
a stair that turns in some configuration using winders to create a circular stair @ the point of rotaion
how can a stair sit in the round
circular stair
spiral stairs
spiral stair
wedge-shaped treads that wind around a central post
what is the difference between a handrail and a guardrail?
handrail= is present to assist a user in safely navigating the stairway- it is what IS HELD ON TO
guardrail= is present to keep a user from FALLING off the stairway- it is like a BARRICADE
guardrail height
42” min off the treads
handrail height
34 - 38” off the tread
