21 sq ft re-roof for sfd if a re-roof project is proposed, the following specifications apply. Existing roofing material ashalt shingles proposed roofing material asphalt shingles manufacturer owens corning esr-1372 brand and model oakridge sierra gray color (if cool roof required) crrc 0890-0013 built-up roofing assembly system number per attached listing report (if applicable) na specific exemption from cool roof requirements (if applicable) na required building inspector field verification (if applicable) yes note self-certification by a licensed contractor is acceptable if a signed letter on company letterhead is provided to the building inspector.