The workshop, held on March 16th, focused on tolerances for surface flatness, smoothness and slope.
The Board’s accessibility guidelines for facilities, including those issued under the Americans with Disabilities Act, recognize conventional industry tolerances for field conditions. The Board receives many inquiries from design, construction, and code professionals on what tolerances are acceptable for a given specification. The Board is sponsoring a project to develop guidance on construction tolerances, particularly those pertaining to the slope, flatness, and smoothness of ground and floor surfaces.
As part of this project, which is being conducted by Architectural Research Consulting, Inc., a workshop was held on March 16th to identify strategies and considerations for developing this guidance. Participants included representatives from various trade associations, professional societies, government agencies, and research organizations. Discussion focused on available measurement protocols for surface flatness, smoothness and slope in relation to construction materials and methods.
Papers presented at the workshop addressed design issues, construction considerations, and findings from a study of the physical effects of wheelchair travel over uneven surfaces. Participants identified ways to advance work on establishing appropriate tolerances and measurement protocols and promoting best practices through various trade and professional associations, including the Construction Specifications Institute, the American Institute of Architects, and the American Concrete Institute, among others. This project, while currently focused on exterior routes, including ramps, will also explore tolerances for other types of construction.
For further information on this project, contact Lois Thibault, the Board's research coordinator at email@example.com, (202) 272-0023 (v), or (202) 272-0082 (TTY).
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