Clear Width (2010 ADAS 403.5.1) vs. Path of Travel—What They Mean and Why They’re Not the Same

Main takeaway:

• Clear width (Section 403.5.1 of the 2010 ADA Standards) is a measurement rule that applies to every accessible walking surface, old or new.

• Path of travel is a scoping rule that applies only during alterations to a primary-function area and governs how far accessibility upgrades must extend. When the two terms are swapped, projects either over-spend on work that isn’t required or, more often, under-provide access.

  
  

1. What Section 403.5.1 Actually Says

• Minimum continuous width: 36 in. (915 mm) on any accessible walking surface, interior or exterior.

• Narrow “pinch points”: may shrink to 32 in. for 24 in. max before widening again.

• At 180° turns around narrow objects, the width must enlarge to 42-48 in.

Think of 403.5.1 as the clear tunnel a wheelchair needs no matter where it goes— hallways, sidewalks, shopping aisles, or ramps.

2. Path of Travel—A Different Concept

Definition (28 CFR 36.403) “A continuous, unobstructed way that connects the altered primary-function area with entrances, parking, sidewalks, restrooms, telephones, and drinking fountains”.

Key features

Feature	Path of Travel Rule
When it applies	Only when altering an area that contains the facility’s primary function (e.g., dining space in a restaurant).
How far it reaches	From the altered space out to site arrival points and the support rooms that serve it.
Cost cap	Upgrades cap at 20% of the project cost; beyond that, they are “disproportionate” and may stop.
Technical specs inside the path	Must meet all access rules, including the 36-in. clear width of 403.5.1.

Bottom line: Path of travel is about scope—how much of the building must be updated during an alteration. 403.5.1 is about dimension—how wide any compliant route must be.

3. Why People Mix Them Up

1. Similar language: Both talk about routes, but “accessible route” is a new-construction term while “path of travel” is an alteration term.

2. Plan notes that say “maintain path of travel 36 in.”—Designers often use the phrase when they merely mean maintain clear width.

3. State overlays (e.g., California CBC) add extra width in some corridors (44 in. or 48 in.), blurring the baseline 36-in. rule.

4. Simple Examples

Scenario	Correct Requirement	Wrong (Common Misuse)
Fresh carpeting in a bank lobby (primary function).	Provide a 36-in. clear aisle and upgrade the route from the entrance to the lobby (doors, ramps) up to 20% of project cost—this is a path of travel issue.	Only replacing carpet without checking doors, ramps, or restroom access.
Building a new 5-ft-wide sidewalk between accessible parking and the entrance.	Sidewalk must stay ≥36 in. clear; no path-of-travel trigger because it’s new work, not an alteration.	Labeling drawings “path of travel” even though no alteration zone exists.
Adding a juice bar inside an existing gym.	Because the juice bar is a new primary-function area, upgrade the route from the main entrance, plus drinking fountain and restroom that serve it (20% cost cap).	Thinking only the juice-bar counter needs access and ignoring the route to the restroom.

5. Quick Checklist for Field Use

1. Is this new construction? → Ignore path-of-travel; just meet 403.5.1 clear width and other technical rules.

2. Is this an alteration affecting a primary-function area? → Identify the path of travel from that area to:  

   1. Exterior approach 

   2. Entrance 

   3. Restrooms/phones/fountains.

3. Cost math: Upgrade elements along the path until the added cost hits 20% of the alteration budget. Prioritize in this order: entrance → route → restroom → phone → fountain.

4. Apply technical specs inside that path: width, slopes, door clearances, etc.

6. Take-Home Rules

• Use “clear width” (403.5.1) when talking inches and all projects.

• Use “path of travel” only when talking alterations, primary-function areas, and cost caps.Keeping the terms straight avoids failed inspections, change orders, and—most important—barriers that still exclude customers.

DISCLAIMER: The information provided in this post is for informational purposes only and does not constitute legal advice. Please consult a qualified attorney or consultant for advice tailored to your situation.