2 x Cavity Wall Combination Extension Sleeves G935
Manthorpe G935 Extension Sleeve
Pack of 2
Extension Sleeve 9" x 3" for cavity wall ventilators.
Part number: G935.
Each pair of extension sleeves adds on a extra 120 - 280mm to the airbrick.
Designed to fit to the back of a G930 airbrick.
Further horizontal extension can be added.
Alternatively it can be stacked to form 9" x 6" or 9" x 9" formations.
Provides a maximum equivalent area of 6600mm²
Meets NHBC requirements for the control of condensation in buildings.
Other ventilation fittings for this product available in our shop.
To provide ventilation for heat producing appliances
To provide background room ventilation
For new build, refurbishment and remedial work
Features & Benefits
Aesthetically pleasing and a simple to install modular system
Excellent airflow properties
Independently tested by BRE
Offers reduction of draughts and light compared to basic through wall ventilation
Internal finish with open louvre grille
Regulations & Standards
BRE Digest 17
BRE Digest 262
Building Regulations C4
NHBC Standards 5.2BS 5250:2011 Control of Condensation in Buildings