khsmith55 said:
Looking for guidance, some current, some historical. Looking at a project constructed under the 1979 UBC but raises questions under the current I-Codes (2003, 2006 and 2009, adopted codes under jurisdictions I work with). The question being, what is the “maximum” slope of a “landing”? In the 1979 UBC ramp requirements did not apply on slopes less than 6.7% (current codes 5%), so if it’s not a “ramp” can it be a landing? Current IBC and ANSI A117.1 limit the slope of “landings” at ramps to 1:48 but I can find no similar limits for stair landings. The 1979 UBC does not have any specific slope limitations for “landings”. As a professional, I have always limited all landing slopes to a maximum of 1/4":12", guess that was a good practice but beyond the code (will still continue to use 1/4":12") requirements. Any help and/or specific code sections will be appreciated.Thanks,
Ken
2006 ed. IBC - 1008.1.4 Floor elevation. There shall be a floor or landing
on each side of a door. Such floor or landing shall be at the
same elevation on each side of the door. Landings shall be
level except for exterior landings, which are permitted to
have a slope not to exceed 0.25 unit vertical in 12 units horizontal
(2-percent slope).
Exceptions:
1. Doors serving individual dwelling units in Groups
R-2 and R-3 where the following apply:
1.1. A door is permitted to open at the top step
of an interior flight of stairs, provided the
door does not swing over the top step.
1.2. Screen doors and storm doors are permitted
to swing over stairs or landings.
2. Exterior doors as provided for in Section 1003.5,
Exception 1, and Section 1018.2, which are not on
an accessible route.
3. In Group R-3 occupancies not required to be
Accessible units, TypeAunits or Type B units, the
landing at an exterior doorway shall not be more
than 7.75 inches (197 mm) below the top of the
threshold, provided the door, other than an exterior
storm or screen door, does not swing over the landing.
4. Variations in elevation due to differences in finish
materials, but not more than 0.5 inch (12.7 mm).
5. Exterior decks, patios or balconies that are part of
Type B dwelling units, have impervious surfaces
and that are not more than 4 inches (102 mm)
below the finished floor level of the adjacent interior
space of the dwelling unit.
If ICC/ANSI A-117.1 referenced
405 Ramps
405.1 General. Ramps along accessible routes
shall comply with Section 405.
405.2 Slope. Ramp runs shall have a running slope
not steeper than 1:12.
EXCEPTION: In existing buildings or facilities,
ramps shall be permitted to have slopes
steeper than 1:12 complying with Table 405.2
where such slopes are necessary due to space
limitations.
405.3 Cross Slope. Cross slope of ramp runs shall
not be steeper than 1:48.
.
