Lew Harriman

Lew Harriman is the Director of Research & Consulting at Mason-Grant. Much of his work over the last 40 years has concerned humidity and moisture control in buildings and industrial processes, along with related phenomena which are affected by humidity and moisture, such as indoor mold, HVAC systems and the drying rates of materials and structures.

Lew has served as a National Peer in the Construction Excellence Program of the Public Buildings Service of the U.S. General Services Administration. He is well-known as a writer and lecturer in North America, Europe and Asia. Lew is a Fellow and Life Member of the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE), and in 2018 he was inducted into the Indoor Air Quality Hall of Fame by the Indoor Air Quality Association.

Lew is the author of The Dehumidification Handbook published by Munters Corporation, and was the lead author and project manager for both the ASHRAE Humidity Control Design Guide and The ASHRAE Guide for Buildings in Hot & Humid Climates. He also wrote the California Builder’s Guide to Avoiding Mold Risk, and served as the Chair of ASHRAE’s Presidential Committee on Indoor Mold. He is an active member of ASHRAE’s Technical Committee 1.12 - Moisture Management in Buildings.

You are invited to contact Lew directly:

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1986 - present: Mason-Grant Consulting - Director of Research & Consulting

1976 - 1986: Munters Dehumidification Division - New Markets and New Product Development

1971 - 1976: US Air Force, HQ Strategic Air Command - Engineering & Services - Housing Management and Construction Planning

1967 - 1971: Dartmouth College, Hanover, NH & Universidad de Salamanca, Spain - AB, Visual Studies/Architecture

1959 - 1967: Calasanctius Preparatory School, Buffalo, NY

1963 - 1964 Escolápios de Puigcerdá, Gerona, Spain


Lew is married to Cynthia W. Harriman, retired Executive Director of the Whole Grains Council. They live in Portsmouth, NH. Their daughter Elizabeth Harriman is a bilingual Korean-English speech-language pathologist, and their son Sam Harriman is a electrician and renewable energy system designer.