C-Thru's engineering plans are approved by the International Code Council (ICC, formerly the ICBO).

C-Thru is a member of the National Sunroom Association (NSA) with a seat on the Board of Directors. 61 C-Thru Sunrooms were nominated for awards in 2006, with 13 finalists and 1 winner.

C-Thru is one of the founding members of the National Patio Enclosure Association and continues to lead the industry in products and innovation.

C-Thru's window systems conform to the standards set forth by the American Architectural Manufacturers Association (AAMA).

C-Thru's patented electrical raceways are approved & classified with Underwriters Laboratories (UL).

C-Thru is registered with the Better Business Bureau with a good rating.

CMBSOA

C-Thru's windows are approved by the California Model Building Security Ordinance Association, which has the strictest set of standards for window security in the U.S.A.

 Florida Approval

Why Florida? Florida has the most stringent hurricane requirements in the U.S.A., and C-Thru's rooms are approved. C-Thru Sunrooms are approved in Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, District of Columbia, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North, Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, and Wisconsin. Wyoming