90mm Mannok IsoCavity Full Fill Cavity Wall Insulation 1200mm x 450mm - 2.16m2 per pack

90mm Mannok IsoCavity Full Fill Cavity Wall Insulation is a rigid PIR insulation board manufactured for masonry cavity walls, where it fills the cavity rather than leaving the wide residual gap a partial fill board demands. It is the entry thickness in the IsoCavity range, sized to suit a standard 100mm cavity, and it replaces Mannok's earlier IsoShield board with a foil facing designed to be easier to handle on site. Each board measures 1200mm x 450mm x 90mm, covering 0.54m² per board, and is supplied in a pack of 4 boards covering 2.16m² per pack. The board has a thermal conductivity of 0.022 W/mK and a thermal resistance of 4.05 m²K/W*, with a compressive strength greater than 140 kPa and a core water vapour resistivity of 300 MNs/gm. Dimensional stability is classified DS(TH)4 to EN 1604, so boards hold their shape and butt tightly to form a continuous insulation layer. Both faces carry a low emissivity composite foil, which raises the thermal resistance of the residual cavity alongside the insulation value of the core itself. The four tongue and groove edges are precision cut so boards interlock as they are placed, helping maintain continuity of insulation across every joint and restricting moisture movement through the joint line. Because the profile does the alignment for you, boards go in square and stay square as the inner leaf is built up. Mannok IsoCavity is used in masonry cavity wall construction and has been tested and certified for a residual cavity of 0mm to 10mm, which is what allows a 90mm board to work in a 100mm cavity. For cavities up to 100mm, Mannok specify wall ties in the inner leaf at maximum 900mm horizontal and 450mm vertical centres, with additional ties at openings and corners, and boards fitted tight against the inner leaf with joints tightly interlocked. Install in line with the latest Mannok technical guidance, the project specification and the relevant Building Regulations. Filling the cavity this way lifts the thermal performance of the wall without adding to its overall thickness, which matters when the footprint and the outer leaf position are already set. Key Benefits of 90mm Mannok IsoCavity: 90mm rigid PIR full fill cavity board sized to suit a standard 100mm masonry cavity. Thermal conductivity of 0.022 W/mK, among the lowest available from rigid board insulation. Thermal resistance of 4.05 m²K/W* for the 90mm board. Tested and certified for a residual cavity of 0mm to 10mm, so more of the cavity width does useful work. Precision cut tongue and groove edges on all four sides for continuity of insulation across joints. Low emissivity composite foil facings on both faces, increasing the thermal resistance of the residual cavity. Compressive strength greater than 140 kPa. DS(TH)4 dimensional stability to EN 1604, allowing boards to be tightly butted into a continuous layer. Zero ozone depletion potential and a global warming potential of less than 5. Fibre free, rot resistant, and does not support mould or fungus. Supplied as 4 boards per pack covering 2.16m². Good to Know: Cavity sizing: the IsoCavity range is built around standard cavity widths, with 90mm for a 100mm cavity, 115mm for 125mm and 140mm for 150mm. Foil facing: the low emissivity foil is a thermal facing. It is not a vapour control layer and does not replace one where the design calls for it. Fire performance: reaction to fire is Euroclass F to BS EN 13501-1, which should be checked against the fire strategy for the building. Keep the cavity clean as you build. Mortar droppings on the block face stop boards seating properly against the inner leaf. Wall insulation should extend 150mm below the upper edge of floor insulation to limit thermal bridging at the floor perimeter. Mannok provide U-value and interstitial condensation calculations for specific wall build-ups through their technical team. For a standard cavity built to a modern specification, the 90mm board is the one that does the most with the width you already have.