Manthorpe Eaves Ventilation Pack (25,000mm2 ) - 6m Pack The Manthorpe 6m Ventilation Pack provides a practical and cost effective solution for roof ventilation requirements. With a 6 metre run of Manthorpe over fascia ventilator, roll panel and felt support tray, all the products supplied in the pack are designed to comply with Building Regulations and British Standards. 25mm  Ventilation Situations. Pack Includes: G500 Roll Panel G1280 Felt Support Tray G1200N/G2500N Over Fascia Vents