Product description
Manthorpe G961 Extension Sleeve
Extension sleeve for telescopic vents.
Can be used for vertical or rear horizontal extension.
Designed to be used with G960 Manthorpe telescopic vents.
Each unit extends the under floor ventilator a further 150mm vertically or 185mm horizontally.
Further extension can be added.
Provides a maximum equivalent area of 6600mm² airflow.
Meets NHBC requirements for the control of condensation in buildings.
Other ventilation fittings for this product available in our shop.
Allows ventilation to an underfloor void.
Allows 2 courses per extension.
BS 5250:2011 Control of Condensation in Building.