3500sf re-roof (hra) from shake to gaf (comp shingles) for existing sfd. If a re-roof project is proposed, the following specifications apply. Existing roofing material: shake proposed roofing material: gaf (comp shingles) manufacturer: gaf brand and model: timberline hd color (if cool roof required): barkwood built-up roofing assembly system number per attached listing report (if applicable): 1475 specific exemption from cool roof requirements (if applicable): radiant barrier required building inspector field verification (if applicable): n a note: self-certification by a licensed contractor is acceptable if a signed letter on company letterhead is provided to the building inspector.