What is a Haag Certified Roof Inspector? A Haag certified Roof Inspector is an individual who has been certified by Haag Engineering, a Forensic Engineering Firm. Haag Engineering was founded in 1924 by Walter G. Haag. Today, they are the premiere Forensic Engineering Firm specializing in storm damage to all roofing applications. Thanks to my training with Haag engineering, I am qualified to determine the cause and origin of a roof system failure. There are numerous factors that can cause a roofing system to fail, ranging from: manufacturing defects, improper installation, mechanical damage, and catastrophic weather events. Haag Certified Inspectors are not beginners in the field. They are adjusters, estimators, home inspectors, roofing contractors, consultants, and other industry pros who have fine-tuned their inspection skills to find damage where it exists. Haag Certified Inspectors are tested professionals who possess the resources to assess the damage with confidence.