4000sf reroof to t. P. O. If a re-roof project is proposed, the following specifications apply. Existing roofing material built up proposed roofing material tpo manufacturer brand and model color (if cool roof required) white built-up roofing assembly system number per attached listing report (if applicable) low slope specific exemption from cool roof requirements (if applicable) required building inspector field verification (if applicable) note self-certification by a licensed contractor is acceptable if a signed letter on company letterhead is provided to the building inspector.