The sleeve prevents the spread of fire between connected compartments. Once exposed to heat, the sleeve expands and crushes the duct. Fire resistance of at least two hours. Will not reduce thermal insulation or vapour seal properties of existing insulation. Only one side of the duct need be accessible for installation.
As such, these sleeves are suitable for retrofit scenarios. Easy cut to fit installation reduces waste. Site time is minimal with no mastic, special tools or training required. Nine available sizes ranging from 100m x 54mm to 308mm x 29mm. Length of all is 180mm. Independently tested and in full compliance with BS 476 Part 22: 1987 and NHBC type approval.