High Capacity Vent Tiles are only available for Cambrian Slates. The Hi-Flow ThruVent Tile is a means of incorporating higher levels of ventilation within the roof slope than the standard ThruVent Tile at high or low level. They can also be used for soil pipe ventilation with no restrictions in usage. Performance Minimum pitch is the minimum pitch of the slate Maximum pitch 90° The effective ventilation area for each Hi-Flow ThruVent Tile is 15,000 mm² for Cambrian To achieve roof space ventilation of 25,000 mm²/m, Hi-Flow ThruVent Tiles should be spaced at 600 mm centres for Cambrian Installation Suitable for roof space ventilation, mechanical extraction and soil vent termination. The Underlay Seal provided should always be installed to maintain the integrity of the roofing underlay. Where Hi-Flow ThruVent Tiles are used in combination with insulation between the rafters, ensure that the pipe on the underside is clear of the insulation, by cutting the pipe where necessary. Hi-Flow ThruVent Tiles are not suitable for hot flue gases, please use the Gas Flue Ridge Terminal. For soil pipe termination do not install within 3 m horizontally and 900 mm vertically of an opening, e.g. roof windows and roof space ventilation.