Storm damage can be a result of straight line winds, tornadic winds, and on rare occasions, lighting. In general, tornadic winds are more likely to damage a structure. Damage can result directly from wind pressure exerted on the structure, latent damage that cannot initially be detected, and from falling debris or missiles. Tornadic winds are capable of coming from any direction, producing winds of up to and greater than 200MPH. Tornadic storms are ranked by intensity from EF-1 to EF-5, one being the least and 5 being the most intense. Storms are categorized by the Enhanced Fujita Scale (EF Scale). Central Mississippi has experienced all categories of these storms including EF-5. Straight line winds are possible at any location. Most straight line wind events, including transient hurricane events, are less than 80MPH (3 sec. gust). This wind speed is below the local design speed required by engineering design (per ASCE 7), however; many structures are not subject to qualified structural engineering design standards or the requirements dictated by the building code; therefore, damage can occur. Depending on the intensity and wind speed, types of damage can range from loosened and missing roofing elements, roof deck, damaged windows, and when deficient structural stiffness exist, building racking can occur and even structural collapse. Openings in the building envelope can result in internal pressures such that over pressurization can occur leading to damage. High winds, straight line or tornadic, will reveal any latent defects or deficiencies that might exist in your home’s construction. These winds can produce suction pressures on the roof that exceed the gravity loads. These pressures can produce net uplift forces at the points of attachment between roof components and their supports, and they can also produce stress reversals in the roof trusses. It is critical that all homes be constructed with sufficient uplift resistance. In residential home construction, one of the most efficient ways to tie a roof component is with Simpson H ties. These ties generally have a cost of $.50 or less and an entire home roof hold down hardware could result in a cost of less than $100.00. Therefore, CMS recommends that all new construction include Simpson hold down hardware. Stress reversals in roof trusses can result in truss web members being required to resist compression forces not present under normal gravity loads. If the web members are not sufficiently braced for these compressive forces, they can result in compression failures. Always insist that your wood truss manufacture design with and your builder adhere to the bracing requirements of the Truss Plate Institute.