{"title":"Wall \u0026 Cavity Insulation","description":null,"products":[{"product_id":"knauf-dritherm-cavity-slab-37-75mm-1200mm-x-455mm-4-36m2","title":"Knauf DriTherm Cavity Slab 37 75mm 1200mm x 455mm (4.36m2)","description":"\u003cdiv class=\"col-xs-12 col-md-6\"\u003e\n\u003cdiv class=\"product-page__body__info-wrapper\"\u003e\n\u003cdiv class=\"text-block small-text color-light-gray\"\u003e\n\u003ch5\u003eProduct Description:\u003c\/h5\u003e\n\u003cp dir=\"ltr\"\u003eKnauf DriTherm Cavity Slab 37 is a non-combustible, water-repellent glass mineral wool slab for full-fill insulation of external masonry cavity walls. Supplied at 75mm thick in 1200 x 455mm slabs covering 4.36m² per pack, it is built into the cavity as the wall is constructed, and suits extensions matching an existing wall, garages and outbuildings, and refurbishment work where a narrower cavity has to be maintained.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eThe 37 designation refers to the slab's thermal conductivity of 0.037 W\/mK, which at 75mm gives an R-value of around 2.03 m²K\/W. In a narrower cavity the conductivity rating carries more weight than it does in a deep one, since there is less depth available to make up the difference, and DriTherm 32 is the higher-performing alternative at the same thickness where a tighter U-value has to be met.\u003c\/p\u003e\n\u003ch5 dir=\"ltr\"\u003eSpecification:\u003cbutton type=\"button\" class=\"btn btn-link lnkChangeSection\"\u003e\u003c\/button\u003e\n\u003c\/h5\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv id=\"accordion\" class=\"product-page__accordian\"\u003e\n\u003cdiv id=\"collapse_specs\" class=\"collapse show\"\u003e\n\u003cdiv class=\"product-page__spec-table-wrapper\"\u003e\n\u003ctable class=\"product-page__spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eKnauf\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eCoverage\u003c\/td\u003e\n\u003ctd\u003e4.36m2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eDepth\u003c\/td\u003e\n\u003ctd\u003e75mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eLength\u003c\/td\u003e\n\u003ctd\u003e1200mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThermal Conductivity\u003c\/td\u003e\n\u003ctd\u003e0.037W\/mk\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThickness\u003c\/td\u003e\n\u003ctd\u003e75mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e455mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"col-xs-12 col-md-6\"\u003e\n\u003cform action=\"https:\/\/www.itsplaneandsimple.com\/products\/setpostcode\" id=\"frmChoosePostcode\"\u003e\n\u003cdiv class=\"row choose-delivery stacked\"\u003e\n\u003cdiv class=\"col-10\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/form\u003e\n\u003cdiv class=\"col-12\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Home \u0026 Trade","offers":[{"title":"Default Title","offer_id":55403681874247,"sku":"INS011","price":25.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/7759\/6999\/files\/INS011.jpg?v=1791879161"},{"product_id":"knauf-dritherm-cavity-slab-37-50mm-1200mm-x-455mm-6-55m2","title":"Knauf DriTherm Cavity Slab 37 50mm 1200mm x 455mm (6.55m2)","description":"\u003cdiv class=\"product-page__body__info-wrapper\"\u003e\n\u003cdiv class=\"text-block small-text color-light-gray\"\u003e\n\u003ch5\u003eProduct Description:\u003c\/h5\u003e\n\u003cp dir=\"ltr\"\u003eKnauf DriTherm Cavity Slab 37 is a non-combustible, water-repellent glass mineral wool slab for full-fill insulation of external masonry cavity walls. Supplied in 1200 x 455mm slabs across a range of thicknesses, it is built into the cavity as the wall is constructed, on new build housing, extensions, garages, and outbuildings.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eFull-fill insulation only works if the cavity is genuinely full, and this is where mineral wool slab has the advantage over rigid board. The slabs are semi-rigid and slightly compressible, so they push tightly against the masonry on both sides, close up around wall ties, and take up the small irregularities in blockwork and mortar squeeze that leave gaps behind a rigid board. Those gaps matter more than their size suggests, as air moving through them carries heat straight past the insulation.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eThe 37 designation refers to the slab's thermal conductivity of 0.037 W\/mK, the standard-performance option in the DriTherm range, with DriTherm 32 available where a tighter U-value has to be met or the cavity is narrower. The slab carries a Euroclass A1 fire classification, the highest available, meaning it makes no contribution to fire, and a water-repellent additive runs through it so that moisture crossing the outer leaf in driving rain is shed rather than absorbed. Build in as the inner leaf rises, fit tightly with no gaps at joints, and keep clear of mortar droppings, which would bridge the cavity.\u003c\/p\u003e\n\u003ch5 dir=\"ltr\"\u003eSpecification:\u003c\/h5\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv id=\"accordion\" class=\"product-page__accordian\"\u003e\n\u003cdiv id=\"collapse_specs\" class=\"collapse show\"\u003e\n\u003cdiv class=\"product-page__spec-table-wrapper\"\u003e\n\u003ctable class=\"product-page__spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eKnauf\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eCoverage\u003c\/td\u003e\n\u003ctd\u003e6.55m2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eDepth\u003c\/td\u003e\n\u003ctd\u003e50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eLength\u003c\/td\u003e\n\u003ctd\u003e1200mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThermal Conductivity\u003c\/td\u003e\n\u003ctd\u003e0.037W\/mk\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThickness\u003c\/td\u003e\n\u003ctd\u003e50mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e455mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Home \u0026 Trade","offers":[{"title":"Default Title","offer_id":55403682103623,"sku":"INS012","price":26.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/7759\/6999\/files\/INS012.jpg?v=1791879161"},{"product_id":"knauf-dritherm-cavity-slab-37-150mm-1200mm-x-455mm-4-36m2","title":"Knauf DriTherm Cavity Slab 37 150mm 1200mm x 455mm (4.36m2)","description":"\u003cdiv class=\"product-page__body__info-wrapper\"\u003e\n\u003cdiv class=\"text-block small-text color-light-gray\"\u003e\n\u003ch5\u003eProduct Description:\u003c\/h5\u003e\n\u003cp dir=\"ltr\"\u003eKnauf DriTherm Cavity Slab 37 is a non-combustible, water-repellent glass mineral wool slab for full-fill insulation of external masonry cavity walls. Supplied at 150mm thick in 1200 x 455mm slabs covering 4.36m² per pack, it is built into the cavity as the wall is constructed, on new build housing, extensions, and outbuildings.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eAt 150mm, this is the depth specified where a demanding U-value has to be met and the cavity has been designed wide enough to take it. The 37 designation refers to the slab's thermal conductivity of 0.037 W\/mK, which at this thickness gives an R-value of around 4.05 m²K\/W. Where a tighter target has to be hit at the same cavity width, DriTherm 32 is the higher-performing alternative.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eThe slab carries a Euroclass A1 fire classification, the highest available, meaning it makes no contribution to fire — an increasingly important consideration in external wall construction. A water-repellent additive runs through the slab, so moisture crossing the outer leaf in driving rain is shed rather than absorbed, keeping the insulation dry and its performance intact. Being semi-rigid and slightly compressible, the slabs push tightly against the masonry on both sides, close up around wall ties, and take up the irregularities in blockwork and mortar squeeze that leave air gaps behind a rigid board. Build in as the inner leaf rises, fit tightly with no gaps at joints, and keep clear of mortar droppings, which would bridge the cavity.\u003c\/p\u003e\n\u003ch5 dir=\"ltr\"\u003eSpecification:\u003c\/h5\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv id=\"accordion\" class=\"product-page__accordian\"\u003e\n\u003cdiv id=\"collapse_specs\" class=\"collapse show\"\u003e\n\u003cdiv class=\"product-page__spec-table-wrapper\"\u003e\n\u003ctable class=\"product-page__spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eKnauf\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eCoverage\u003c\/td\u003e\n\u003ctd\u003e4.36m2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eDepth\u003c\/td\u003e\n\u003ctd\u003e150mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eLength\u003c\/td\u003e\n\u003ctd\u003e1200mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThermal Conductivity\u003c\/td\u003e\n\u003ctd\u003e0.037W\/mk\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThickness\u003c\/td\u003e\n\u003ctd\u003e150mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e455mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Home \u0026 Trade","offers":[{"title":"Default Title","offer_id":55403682365767,"sku":"INS008","price":40.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/7759\/6999\/files\/INS008.jpg?v=1791879162"},{"product_id":"knauf-dritherm-cavity-slab-37-100mm-1200mm-x-455mm-6-55m2","title":"Knauf DriTherm Cavity Slab 37 100mm 1200mm x 455mm (6.55m2)","description":"\u003cdiv class=\"col-xs-12 col-md-6\"\u003e\n\u003cdiv class=\"product-page__body__info-wrapper\"\u003e\n\u003cdiv class=\"text-block small-text color-light-gray\"\u003e\n\u003ch5\u003eProduct Description:\u003c\/h5\u003e\n\u003cp dir=\"ltr\"\u003eKnauf DriTherm Cavity Slab 37 is a non-combustible, water-repellent glass mineral wool slab for full-fill insulation of external masonry cavity walls. Supplied at 100mm thick in 1200 x 455mm slabs covering 6.55m² per pack, it is built into the cavity as the wall is constructed, on new build housing, extensions, garages, and outbuildings.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eThe 37 designation refers to the slab's thermal conductivity of 0.037 W\/mK, giving an R-value of around 2.7 m²K\/W at 100mm. It is the standard-performance option in the DriTherm range, suited to projects where the U-value can be met comfortably at the cavity width available, with the higher-performing DriTherm 32 used where the target is tighter or the cavity narrower.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eThe slab carries a Euroclass A1 fire classification, the highest available, meaning it makes no contribution to fire — an increasingly important consideration in external wall construction. A water-repellent additive runs through the slab so that moisture crossing the outer leaf in driving rain is shed rather than absorbed, keeping the insulation dry and its thermal performance intact in exposed positions. Being semi-rigid and slightly compressible, the slabs push tightly against the masonry on both sides, close up around wall ties, and take up the irregularities in blockwork and mortar squeeze that leave air gaps behind a rigid board. Build in as the inner leaf rises, fit tightly with no gaps at joints, and keep clear of mortar droppings, which would bridge the cavity.\u003c\/p\u003e\n\u003ch5 dir=\"ltr\"\u003eSpecification:\u003c\/h5\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv id=\"accordion\" class=\"product-page__accordian\"\u003e\n\u003cdiv id=\"collapse_specs\" class=\"collapse show\"\u003e\n\u003cdiv class=\"product-page__spec-table-wrapper\"\u003e\n\u003ctable class=\"product-page__spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eKnauf\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eCoverage\u003c\/td\u003e\n\u003ctd\u003e6.55m2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eDepth\u003c\/td\u003e\n\u003ctd\u003e100mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eLength\u003c\/td\u003e\n\u003ctd\u003e1200mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThermal Conductivity\u003c\/td\u003e\n\u003ctd\u003e0.037W\/mk\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThickness\u003c\/td\u003e\n\u003ctd\u003e100mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e455mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"col-xs-12 col-md-6\"\u003e\n\u003cform action=\"https:\/\/www.itsplaneandsimple.com\/products\/setpostcode\" id=\"frmChoosePostcode\"\u003e\n\u003cdiv class=\"row choose-delivery stacked\"\u003e\n\u003cdiv class=\"col-10\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/form\u003e\n\u003cdiv class=\"col-12\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Home \u0026 Trade","offers":[{"title":"Default Title","offer_id":55403682464071,"sku":"INS009","price":40.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/7759\/6999\/files\/INS009.jpg?v=1791879164"},{"product_id":"knauf-dritherm-cavity-slab-32-75mm-1200mm-x-455mm-3-27m2","title":"Knauf DriTherm Cavity Slab 32 75mm 1200mm x 455mm (3.27m2)","description":"\u003cdiv class=\"col-xs-12 col-md-6\"\u003e\n\u003cdiv class=\"product-page__body__info-wrapper\"\u003e\n\u003cdiv class=\"text-block small-text color-light-gray\"\u003e\n\u003ch5\u003eProduct Description:\u003c\/h5\u003e\n\u003cp dir=\"ltr\"\u003eKnauf DriTherm Cavity Slab 32 is a water-repellent glass mineral wool slab designed for full-fill insulation of external masonry cavity walls. Supplied at 75mm thick in 1200 x 455mm slabs, it is built into the cavity as the wall is constructed, and is the thickness used where the cavity is narrower than modern new build standard — on extensions matching an existing wall, garages and outbuildings, and refurbishment or rebuilding work on older properties.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eThe 32 designation refers to the slab's thermal conductivity of 0.032 W\/mK, which at 75mm gives an R-value of around 2.34 m²K\/W. In a narrow cavity, that conductivity rating matters more than it does in a deep one: with less depth available, the quality of the insulation is the only variable left, and a lower-performing product in a 75mm cavity may not reach the required U-value at all.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eFull-fill insulation works only if the cavity is genuinely full, which is where mineral wool slab has the advantage over rigid board. The slabs are semi-rigid and slightly compressible, so they push tightly against the masonry on both sides, close up around wall ties, and take up the small irregularities in blockwork and mortar squeeze that leave gaps behind a rigid board. A water-repellent additive runs through the slab, so moisture crossing the outer leaf in driving rain is shed rather than absorbed. Slabs should be built in as the inner leaf rises, fitted tightly with no gaps at joints, and kept clear of mortar droppings, which would otherwise bridge the cavity.\u003c\/p\u003e\n\u003ch5 dir=\"ltr\"\u003eSpecification:\u003cbutton type=\"button\" class=\"btn btn-link lnkChangeSection\"\u003e\u003c\/button\u003e\n\u003c\/h5\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv id=\"accordion\" class=\"product-page__accordian\"\u003e\n\u003cdiv id=\"collapse_specs\" class=\"collapse show\"\u003e\n\u003cdiv class=\"product-page__spec-table-wrapper\"\u003e\n\u003ctable class=\"product-page__spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eKnauf\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eCoverage\u003c\/td\u003e\n\u003ctd\u003e3.27m2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eDepth\u003c\/td\u003e\n\u003ctd\u003e75mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eLength\u003c\/td\u003e\n\u003ctd\u003e1200mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThermal Conductivity\u003c\/td\u003e\n\u003ctd\u003e0.032W\/mk\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThickness\u003c\/td\u003e\n\u003ctd\u003e75mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e455mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"col-xs-12 col-md-6\"\u003e\n\u003cform action=\"https:\/\/www.itsplaneandsimple.com\/products\/setpostcode\" id=\"frmChoosePostcode\"\u003e\n\u003cdiv class=\"row choose-delivery stacked\"\u003e\n\u003cdiv class=\"col-10\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/form\u003e\n\u003cdiv class=\"col-12\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Home \u0026 Trade","offers":[{"title":"Default Title","offer_id":55403682660679,"sku":"INS016","price":25.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/7759\/6999\/files\/INS016.jpg?v=1791879164"},{"product_id":"knauf-dritherm-cavity-slab-32-150mm-1200mm-x-455mm-2-18m2","title":"Knauf DriTherm Cavity Slab 32 150mm 1200mm x 455mm (2.18m2)","description":"\u003ch5\u003eProduct Description:\u003c\/h5\u003e\n\u003cp dir=\"ltr\"\u003eKnauf DriTherm Cavity Slab 32 is a water-repellent glass mineral wool slab designed for full-fill insulation of external masonry cavity walls. Supplied at 150mm thick in 1200 x 455mm slabs covering 2.18m² per pack, it is built into the cavity as the wall is constructed, on new build housing, extensions, and outbuildings.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eAt 150mm, this is the thickness specified where a demanding U-value has to be met and the cavity has been designed deep enough to take it. The 32 designation refers to the slab's thermal conductivity of 0.032 W\/mK, which at this depth gives an R-value of around 4.69 m²K\/W — a substantial improvement over a 100mm cavity and the kind of performance now expected on new build work under current Building Regulations.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eFull-fill insulation works only if the cavity is genuinely full, which is where mineral wool slab has the advantage over rigid board. The slabs are semi-rigid and slightly compressible, so they push tightly against the masonry on both sides, close up around wall ties, and absorb the small irregularities in blockwork and mortar squeeze that leave gaps behind a rigid board. A water-repellent additive runs through the slab, so moisture crossing the outer leaf in driving rain is shed rather than absorbed, keeping the insulation dry and its performance intact. Slabs should be built in as the inner leaf rises, fitted tightly with no gaps at joints, and kept clear of mortar droppings, which would otherwise bridge the cavity.\u003c\/p\u003e","brand":"Home \u0026 Trade","offers":[{"title":"Default Title","offer_id":55403682791751,"sku":"INS013","price":42.5,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/7759\/6999\/files\/INS014_3dd272eb-972d-49f1-9ff9-8c4b6bb5334e.jpg?v=1791879165"},{"product_id":"knauf-dritherm-cavity-slab-32-100mm-1200mm-x-455mm-3-27m2","title":"Knauf DriTherm Cavity Slab 32 100mm 1200mm x 455mm (3.27m2)","description":"\u003cdiv class=\"product-page__body__info-wrapper\"\u003e\n\u003cdiv class=\"text-block small-text color-light-gray\"\u003e\n\u003ch5\u003eProduct Description:\u003c\/h5\u003e\n\u003cp dir=\"ltr\"\u003eKnauf DriTherm Cavity Slab 32 is a water-repellent glass mineral wool slab designed for full-fill insulation of external masonry cavity walls. Supplied at 100mm thick in 1200 x 455mm slabs covering 3.27m² per pack, it is built into the cavity as the wall is constructed, on new build housing, extensions, garages, and outbuildings.\u003c\/p\u003e\n\u003cp dir=\"ltr\"\u003eFull-fill insulation works only if the cavity is genuinely full, and this is where mineral wool slab has the advantage over rigid board. The slabs are semi-rigid and slightly compressible, so they push tightly against the masonry on both sides, close up around wall ties, and take up the small irregularities in blockwork and mortar squeeze that leave gaps behind a rigid board. Those gaps matter more than their size suggests: air moving through them carries heat straight past the insulation, so a wall with small voids performs noticeably worse than its calculated U-value.\u003c\/p\u003e\n\u003ch5 dir=\"ltr\"\u003eSpecification:\u003c\/h5\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv id=\"accordion\" class=\"product-page__accordian\"\u003e\n\u003cdiv id=\"collapse_specs\" class=\"collapse show\"\u003e\n\u003cdiv class=\"product-page__spec-table-wrapper\"\u003e\n\u003ctable class=\"product-page__spec-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eKnauf\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eCoverage\u003c\/td\u003e\n\u003ctd\u003e3.27m2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eDepth\u003c\/td\u003e\n\u003ctd\u003e100mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eLength\u003c\/td\u003e\n\u003ctd\u003e1200mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThermal Conductivity\u003c\/td\u003e\n\u003ctd\u003e0.032W\/mk\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eThickness\u003c\/td\u003e\n\u003ctd\u003e100mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"product-page__spec-table__heading\"\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e455mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Home \u0026 Trade","offers":[{"title":"Default Title","offer_id":55403682922823,"sku":"INS014","price":42.5,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1016\/7759\/6999\/files\/INS014.jpg?v=1791879165"}],"url":"https:\/\/homeandtrade.co.uk\/collections\/wall-cavity-insulation.oembed","provider":"Home \u0026 Trade","version":"1.0","type":"link"}