GARDNER TPI Vent Ceilings are boards sized at 600 x 1200mm and feature pre-cut holes that are specifically designed to facilitate passive cooling by allowing air to circulate through and cool the roof area of a building. These ceiling boards are typically used for exterior ceilings or overhangs. The pre-cut holes of the Classic Vent Ceiling are arranged symmetrically to accommodate various overhang widths. GARDNER TPI Vent Ceiling are perfect for exterior ceilings or overhangs.