Nystrom Construction LLC, 2340 Washington Ave, Minneapolis, MN 55411, US

Established in 1986, Roof Spec Inc. (RSI) is one of the leading companies in commercial and educational facilities, historic restoration and preservation. It is an independent engineering firm, specializing in the evaluation, design, management and construction observation services of the building envelope, which includes commercial roofing and waterproofing. Located in Minnesota, the firm offers a range of services, such as independent consulting, laboratory analysis, infrared imaging, specification and design services, construction administration and many more. Roof Spec Inc. (RSI) deals in consulting in the design, review and evaluation of commercial roof systems. The company has worked on several projects, such as The Saint Paul Cathedral, the Governor's Ceremonial Mansion, the James J. Hill House and many more.