Planning for Accessibility Success

Planning for Accessibility Success

Accessibility Success- Measurement of threshold

How can a project team plan for accessibility success in their design and construction projects?

We break it down for you in three simple steps.


1. Don’t design to the minimum   

Measurement standards and construction tolerances are typical concepts in all areas of design and construction. The question is often “how much off can something be?” Where accessibility is concerned, construction tolerances are not so simple.

ADA Standards depicts 3 types of dimensions:

  1. Exact or absolute dimension.
  2. A range, specifying an upper and lower limit.
  3. An open range dimension, with only one limit – either a minimum or maximum.

 ADA Standards and other accessibility guidelines recognize construction tolerances but don’t identify acceptable tolerances for specific measurements. The construction industry offers some guidance on tolerances, based on methods and materials used, but the information is not definitive and doesn’t cover all conditions. 

What is an architect or owner to do to achieve accessibility success? 

  • Consider details and measurements at the design stage. At the construction stage, it will cause change orders, schedule delays, and increases in costs.
  • Don’t use the limit if a measurement is specified in the Standards. Build in tolerance early in plans. For example, dimension light switches at 46 inches high instead of the maximum 48 inches.
  • Construction tolerances are not uniformly understood by designers, contractors, and supervisors. It’s safer to build the tolerances into the design than to assume a detail will be built to the exact measurement specified in contract documents.
  • When given a range, the construction tolerance is included in the range. Don’t build to the minimum or maximum or you might exceed the range through construction variations. For example, dimension water closet center lines to 17 inches, which is in the middle of the 16 to 18 inch range.
  • When a hard number is called for in an accessibility standard, anticipate in your drawings the typical tolerances expected in construction trades.

2. Know all the requirements

Have someone on your team that knows all the requirements for ADA compliance. Do an analysis of what compliance regulations will apply and consider the function of a space. Functions such as recreational facilities, specialized pool areas, multi-level dining areas, and shopping centers have special requirements.

The combination of federal, state, and local codes is confusing. It’s not always clear which apply and interpretations of requirements are not always black and white. Have a team member who knows the range of requirements and can navigate the nuances of accessibility standards and codes.

Be mindful that local city or county codes may have more restrictive requirements that provide for greater access than state or federal regulations. The interplay between all requirements can be complex.  Know which standards are most applicable to your project, and be sure you’re using the most current versions.

For example, in California dimensions in restrooms are very different. The height of the paper towel dispenser control must be a maximum of 40” in California, while in the 2010 ADA Standard it is 48” maximum.

3. Check and double check

Any carpenter or seamstress knows the wisdom of “measure twice and cut once.” Mistakes can mean additional labor and material costs for owners and builders too. Working with an expert prevents design and construction miscalculations that add to your financial risks.

An accessibility consultant checks for compliance early. The client makes the proposed recommendations. The accessibility consultant checks for compliance again. The goal is to “cut once” and achieve accessibility success.


Learn how LCM can help your company achieve accessibility success.

Scroll to Top
Skip to content