St. Louis, Mo.—The American Society of Concrete Contractors (ASCC) has published Tolerances for Cast-In-Place Concrete Buildings: A Guide for Specifiers, Contractors and Inspectors, written by Bruce Suprenant, Ph.D., P.E., and Ward Malisch, Ph.D., P.E. The authors suggest tolerances that are based on as-built measurements of buildings and other structures that have performed satisfactorily.

The book includes:

  • a history of cast-in-place concrete tolerances,
  • as-built measurements that support realistic and achievable tolerances, and
  • rational suggested tolerances based on as-built measurements.

The book is divided into two sections. Section 1 includes the suggested tolerance language to be included in specifications. Section 2 gives extensive background information to support the tolerances in Section 1. The book will help owners, specifiers, and contractors to avoid the tolerance traps that cause schedule delays, construction claims, and their associated costs.

Disputes involving cast-in-place concrete tolerances cost owners, specifiers, and contractors time and money. The problem stems from tolerances that are virtually unachievable. For the first time the ASCC compares concrete tolerance requirements with as-built measurements of concrete structures, which show that many accepted tolerances can result in schedule delays, construction claims, and avoidable costs for arbitration or litigation.

Suprenant is the founder and owner of Concrete Engineering Specialists, a concrete consulting firm based in Boulder, Colo. Malisch is the technical director of the ASCC. He was senior managing director of the American Concrete Institute. Both were editors of Concrete Construction magazine.

The ASCC is a non-profit organization dedicated to enhancing the capabilities of those who build with concrete, and to providing them a unified voice in the construction industry. Members include concrete contracting firms, manufacturers, suppliers and others interested in the concrete industry, such as architects, specifiers and distributors. There are approximately 560 member companies in the United States and five foreign countries. To order the book or for more information visit or call 866-788-2722.