125mm Knauf DriTherm Cavity Wall Insulation Slab 37 (3.28m2/Pack)

Full-fill glass mineral wool insulation slab, measuring 125mm in thickness, for use in masonry cavity walls.Produced with a high recycled glass content and ECOSE® Technology, it delivers strong thermal insulation while allowing vapour to pass through, supporting a healthier building fabric.A thermal conductivity of 0.037 W/mK ensures effective energy efficiency, reducing heat loss and supporting compliance with modern Building Regulations.With a Euroclass A1 non-combustible rating and full BBA certification for every UK exposure zone, it also delivers confidence in fire protection, durability, and performance over time.At 125mm thick, the slab is designed for wider cavity walls in new build housing, offering a higher level of thermal performance than mid-range options such as 100mm. This increased depth helps achieve lower U-values in line with stricter energy efficiency targets, while still allowing full-fill installation in a single layer.