Construction Services

1-800 NATIONAL®

Meet the team

Your resource

Have a unique situation or application involving gypsum-based materials, finishing products or cement board? Call our experts at 1-800-NATIONAL® for help.


A free phone call from anywhere in the U.S. and Canada puts you directly in touch with National Gypsum's database of current technical information.


1-800-NATIONAL (1-800-628-4662)

8:00 a.m. - 4:45 p.m. ET | Monday-Friday
Email: techservice@nationalgypsum.com

National gypsum 800 national team

More than 90 years construction experience

Whether it's a question about specifications, code regulations, product usage or installation, the 1-800-NATIONAL Construction Services hotline offers help from these experts:


Mark Chapman, ASTM

Mark, team leader within the 1-800-NATIONAL Construction Services Department, came from our research center where he spent years developing and testing National Gypsum construction systems. As a research engineer, he has extensive knowledge in the structural, fire and sound characteristics of our products and hands-on experience in both residential and commercial construction. With four decades of construction expertise, Mark also has an in-depth understanding of plaster products and their applications.


Jim Farrell

Jim brings over 30 years of construction experience to our 1-800 NATIONAL team, serving as a project manager and GC/owner's representative in various residential and commercial projects, including Class A commercial high and mid-rise construction, healthcare facilities, mixed-use facilities, single-family residential, multifamily and senior living communities. His knowledge brings extensive planning, pre-construction, design, construction and project completion experience to the team. Jim has a degree in Structural Design and Construction Engineering/Construction Management and Electrical Engineering.


Sam Halverson

Sam adds more than 20 years of architectural experience to the 1-800 NATIONAL Construction Services Department. He's worked on developing projects from conception through their final construction. Sam has extensive client management experience as it relates to project schedules, budgets, drawings, permits, bids and specifications. Additionally, he is extremely talented as the creator and manager of BIM technology. Sam holds a degree in Architecture.