National Storm Shelters, LLC is backed with 15 plus years of experience in manufacturing and machining. The business was formed when the F4 tornado hit Murfreesboro, TN in 2009. NSS President decided to begin building underground storm shelters so that people in the Middle TN community could have options and be safe. NSS creates an underground storm shelter product that fits into the floor of your garage and is accessible while your car is in the garage.