Reach range: 15-48 in AFF for forward + side reaches; obstructed reach reduces high reach to 44 in
US Access Board ABA §308 Reach rangesDescription
Accessible reach ranges: unobstructed forward or side reach: 15 in (low) to 48 in (high) above the floor. Where the reach is obstructed (e.g. counter, base cabinet, deep shelf): the maximum high reach is 44 in if the obstruction is up to 20 in deep, OR 46 in if the obstruction is up to 25 in deep (provided knee space + max obstruction depth match). Reach over an obstruction wider than 25 in is NOT accessible.
Why this exists
These reach ranges set every accessible control + outlet height — light switches, thermostats, electrical outlets, cabinet handles. Architects should default to 44-48 in for switches (works for seated + standing), 15-18 in for outlets above floor, and 44 in max for thermostats. NKBA + FHA reach-range directives say similar things.
Measurements
| Property | Operator | Value | Unit | Note |
|---|---|---|---|---|
lowUnobstructed | min | 15 | in AFF | Low limit unobstructed |
highUnobstructed | max | 48 | in AFF | High limit unobstructed |
highObstructed20 | max | 44 | in AFF | High limit over 20-in-deep obstruction |
highObstructed25 | max | 46 | in AFF | High limit over 25-in-deep obstruction |
Categories
Source
Solver enforcement
Browsable only — the solver does not currently enforce this directive (no spec-level data to check against). This entry exists so the architect personas can cite it in conversation and the user can read what the rule says.
Related directives
- Bathroom entry doorway · NKBA Bath 1
- Kitchen walkway and work-aisle widths · NKBA Kitchen 6
- Single-door clear opening: 34" minimum (36" door leaf) · NKBA 4th ed §1.1 Doorways
- Wheelchair-maneuvering clearance at doorways · NKBA 4th ed §1.1 Doorways
- Flush flooring transitions; max 1/4" eased, 1/2" beveled · NKBA 4th ed §1.3 Floor Transitions
Last reviewed 2026-05-15.