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Section 2
ADA Design Overview
Fall, 2017
Ann Johnson, PE Services
Brady Rutman, SRF Consulting Group
ADA Design Overview
Overview
• Pedestrian Access Routes
• Pedestrian Curb Ramps
• Accessible Pedestrian Signals
• Alternate Pedestrian Access Routes
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Pedestrian Access Routes
Pedestrian Access Route (PAR) = A continuous and
unobstructed walkway within a pedestrian circulation route that is specifically
designed for ADA-accessible pedestrian travel
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Pedestrian Access Routes
• Critical Components– Pavement Surface
– Width
– Running Slope
– Cross Slope
– Accessible Parking
– Intersections
– Crosswalks
– Doors & Doorways
– Stairs & Ramps
– Landings
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Pedestrian Access Routes
• Pavement Surface– Stable, Firm, Slip-Resistant
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Pedestrian Access Routes
• Pavement Surface– Stable, Firm, Slip-Resistant
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Pedestrian Access Routes
• Pavement Surface
(Non-Compliant)
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Pedestrian Access Routes
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• Width– Clear width must have a minimum of 4’ (Ideally at least 5’)
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Pedestrian Access Routes
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• Width– Clear width must include passing spaces if less than 5’
– 32” absolute minimum adjacent to protrusion/obstruction
Pedestrian Access Routes
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• Running Slope– Maximum slope of 1:20 (5.0%) along primary direction of
travel (OR match existing roadway slope)
– Slopes greater than 5.0% are “ramps” and must have
landings (and often handrails)
Pedestrian Access Routes
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• Cross Slope– Slope perpendicular to main direction of travel must not be
steeper than 1:48 (~2.0%)
Pedestrian Access Routes
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• Accessible Parking Lots– Reserved Accessible Parking Stalls
– Access Aisle
• 2.0% Maximum Slope in ANY Direction
– Connected to PAR
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Pedestrian Access Routes
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• Intersections & Crosswalks
Urban or High
Pedestrian Traffic
Areas
Pedestrian Access Routes
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• Intersections & Crosswalks
Pedestrian Access Routes
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• Intersections & Crosswalks
Pedestrian Access Routes
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• Intersections & Crosswalks
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Pedestrian Access Routes
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• Intersections & Crosswalks
Pedestrian Access Routes
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• Doors & Doorways
Pedestrian Access Routes
• Stair & Ramp Components– Running Slope & Cross Slope
– Landings & Turning Space
– Geometry
• Width
• Tread/Riser Design
– Handrails
– Edge Protection
– Condition
• Vertical Discontinuities
• Cracking/Crumbling
• Surface Characteristics19
Pedestrian Access Routes
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• Stairs & Ramps
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Pedestrian Access Routes
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• Landings– Minimum dimensions: 4’x4’
– Maximum slope: 2% in ANY direction
Pedestrian Access Routes
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• Landings– All grade breaks within the PAR shall be constructed
perpendicular to the path of travel
Pedestrian Curb Ramps
Curb Ramp Components– Running (Ramp) Slope
– Cross-Slope
– Landings
– Approach
– Ramp Length and Width
– Detectable Warnings
– Ramp Flares
– Curb Tapers
– Grade Breaks
– Gutter Slope
– Counter Slope
– Physical Condition
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Pedestrian Curb Ramps
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Curb Ramp Components
Running (Ramp) Slope Cross-Slope
Maximum 8.3% (1:12) Maximum 2.0% (1:48)
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Pedestrian Curb Ramps
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Curb Ramp Components
Landings
A Level Space for Maneuvering: Required at the top of ramps
exceeding 5.0% and at any change of direction
Minimum Dimensions: 4’ X 4’ (Preferred 5’ X 5’ or full walk width)
Maximum 2% Slope in ANY DIRECTION
Pedestrian Curb Ramps
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Curb Ramp Components
Approach
Pavement leading to the top of the ramp
May be parallel or perpendicular to curb
Ramp Length
Must be long enough to achieve height
of curb at less than 8.3% slope
May not exceed 15’ without an
intermediate landing (30” rise)
Ramp Width
Must be a minimum of 4’
Pedestrian Curb Ramps
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Curb Ramp Components
Detectable Warnings (Truncated Domes)
Purpose: To inform pedestrian of the roadway edge
Extend full width of ramp (within 3” on each end)
Minimum of 24” continuous depth in direction of travel
Place within 3-6” of back of curb or edge of roadway
Color to contrast with concrete
Pedestrian Curb Ramps
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Curb Ramp Components
Ramp Flares and Curb Transitions
Walkable Surfaces
1:10 (10%) Maximum Flare Slope
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Pedestrian Curb Ramps
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Curb Ramp Components
Ramp Flares and Curb Transitions
Non-Walkable Surfaces
1:6 Concrete Flare OR
1:6 Graded Flare OR
Returned Curb
Pedestrian Curb Ramps
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Curb Ramp Components
Grade Breaks
Lines that separate the ramp itself from landings and flares
Shall be perpendicular to the path of travel
Contraction joints to be constructed along grade breaks
Pedestrian Curb Ramps
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Curb Ramp Components
Gutter Slope
Slope of gutter flow line across
bottom of ramp
Maximum 2.0% slope
Counter Slope
Cross slope of roadway or
curb at bottom of ramp
Maximum 5.0% slope
Pedestrian Curb Ramps
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Curb Ramp Components
Physical Condition
Ramps can be non-compliant due to their poor physical condition:
Poor Drainage, Cracking/Crumbling, Vertical Discontinuities, Etc.
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Accessible Pedestrian Signals
• Accessible Pedestrian Signal (APS) = A signal that
communicates information about the “Walk” phase
in audible and vibrotactile formats
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Temporary Pedestrian Access Routes
• Alternate Pedestrian Access Route (APAR)
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Temporary Pedestrian Access Routes
• Example
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