Roofing components and designs are regulated to ensure safety, and zoning laws often regulate which types of roofs can be installed and how they can be installed. In addition, roofers are often required to have specific training to ensure their safety.
Roofing regulations vary across the nation. In Florida, where major hurricanes are fairly common, roofs must be able to withstand winds of a certain strength. In California, roofs must be able to withstand earthquakes without falling. Parts of the country where extreme weather events are less common might have fewer regulations. In addition, zoning laws might forbid certain types of roofs in certain areas. In residential areas, for example, commercial roofing material might not be allowed for aesthetic or safety reasons.
Roofing work is often regulated as well. To make sure roofs are installed in a safe manner, counties likely require permits for roofing work, and the permitting process might require plans for how professionals intend to perform the work. In addition, weather conditions might not allow roofers to work during certain times. Because roofing is such a dangerous job, roofers might have to get proper certification to ensure that they know about ladder safety and how to avoid electrocution when working near wires. Contractor and subcontractors likely need certain types of certification as well.