24 sf reroof for existing sfd. If a re-roof project is proposed, the following specifications apply. Existing roofing material comp proposed roofing material comp manufacturer owens corning brand and model duration lifetime color (if cool roof required) brown wood built-up roofing assembly system number per attached listing report (if applicable) na specific exemption from cool roof requirements (if applicable) r38 to be installed required building inspector field verification (if applicable) na note self-certification by a licensed contractor is acceptable if a signed letter on company letterhead is provided to the building inspector.