The GV11 Compact In-Line Slate Ventilator is designed for high or low level roof space ventilation on new or existing roofs. Can be used as an SVP or extract fan terminal in conjunction with a pipe adapter. Suitable for use with a wide range of slate sizes especially the smaller natural slates typically found in Scotland and Ireland. The GV11 is also AA fire rated and offers superior wind uplift resistance. Terminal performance Airflow resistance with Soil Universal Adapter at:54m3/h (15 litres/sec): 10Pa.108m3/h (30 litres/sec): 42Pa.216m3/h (60 litres/sec): 162Pa. Ventilation area Nett free ventilation area 10,000mm2.Spacing: 2.0m for 5,000mm2/m.1.0m for 10,000mm2/m.0.4m for 25,000mm2/m.