Pack of 20, durable and discrete 1m long (2 x 500mm) interlocking eaves vents, providing continuous eaves ventilation equivalent of continuous 10mm opening. Encourages airflow, allowing the roof to breathe and discourages birds and large insects. Each lightweight polypropylene vent features stop beads that simplify the fitting to top edge of fascia board and integral nail holes for consistent and secure fixings. Inadequate ventilation in the roof space encourages moisture, which can damage roof timbers. All new-build properties must have continuous ventilation at eaves level to avoid damp and condensation within the roof void and to comply with Building Regulations. This 10mm capacity eaves vent is recommended for conventional cold roofs and provides the equivalent of a continuous 10mm opening. The 25mm capacity vent provides the equivalent of a continuous 25mm opening and should be chosen for warm roofs, flat roofs and roof with pitch less than 14°.