H-5 Task 2 Flashcards
what are the three categories of stairs in the BC Building Code?
Service stairs, Private stairs, Public stair
what are service stairs used for?
access service rooms or spaces
(stairs to an attic or utility room)
these stairs cannot access any living space
what are private stairs used for?
interior stairs within a dwelling unit, or exterior stairs serving a single dwelling unit
private or public:
stairs in a multi-family housing development, stairs within that unit serving that single family are?
Stairs shared by several units are?
Private for stair within the unit, public for stairs shared by several units
Public or Private or service:
which is subject to constraints in part 3 of the BC Building Code Book?
Public stairs, (schools, parkades, and other public buildings)
what is the main concern of the BC Building Code when designing and building stairs?
Safety
example, high riser and the run is short, stairs will be quite steep. Conversely, if the rise is too low and the run is too long, the stairs will be very flat.
both situations are dangerous and you don’t want anyone tripping
for private stairs, whats the minimum and maximum rise?
what is the most comfortable rise?
125mm to 200mm
180mm (7”) is most comfortable
within a single flight, all rises and run must be identical. what is the maximum difference in the rise or run of any two steps in a stairway?
whats the maximum difference in the rise or run between adjacent steps in a stairway?
10mm in the rise or run of any two steps in a stairway
5mm in the rise or run between adjacent steps in a stairway
whats the minimum and maximum run for private stairs?
255mm
355mm
thickness for lumber or plywood treads for stairs must be at least?
if open risers are used and the distance between stringers exceeds 750mm, whats the minimum thickness?
25mm
38mm
what does “tread depth” refer to?
the width of the tread, not the length of the tread.
what is the angle of stairs?
degrees
preferred is between 30 and 35 degrees, a 7 in 10 stair has a slope of 35 degrees
what is the minimum headroom height for a dwelling unit? (one building, one fam)
1950mm for within dwelling units, 2050mm for all other stairs
what is the minimum effective depth for stringers? and what is the minimum overall width of the stringer?
Effective depth of at least 90mm, and overall depth of at least 235mm
what is the minimum thickness of a stringer for supported and unsupported along their length?
25mm for supported, 38mm for unsupported
what is the maximum spacing of stringers? and what is it the spacing increased to if a riser board supports the leading edge of the tread?
what is the spacing for serving other than single-family unit?
900mm o.c., 1200mm o.c. if riser board supports tread
600mm o.c. whether the riser supports the tread or not
this is minimum, good practice to include a third stringer
when are handrails required?
where do the handrails run?
handrail must be provided on at least one side of stairways within dwelling units less than?
when their are more than two risers within a dwelling unit
run continuously along the length of the stairway, including the landings, except where interrupted by doorways, newels or changes in direction
1100mm wide
what is the minimum and maximum height of handrails?
what is the clearance from the wall for handrails?
between 865mm to 1070mm in height, measured vertically from the nosing line
50mm
how wide are handrails?
handrails must be graspable, without stretching their hand
what is the minimum width of a stairway?
single dwelling unit
860mm width between wall faces
what takes precedence over proportioning formulas?
BC Building Code minimum 255mm
