{"title":"Roof Insulation","description":"\u003cp\u003eRigid insulation boards for warm flat roofs and pitched roof construction. On a warm roof the insulation sits above the deck and below the waterproofing, which keeps the structural timbers on the warm side of the insulation and largely removes the condensation risk that comes with older cold-roof build-ups.\u003c\/p\u003e\u003ch2\u003eA typical warm flat roof build-up\u003c\/h2\u003e\u003cp\u003eFrom the inside out: structural deck, vapour control layer, rigid insulation board, then the waterproofing membrane bonded over the top. Getting the vapour control layer continuous and sealed matters as much as the insulation itself — gaps let warm moist air reach the cold side of the boards.\u003c\/p\u003e\u003ch2\u003eHow much do you need?\u003c\/h2\u003e\u003cp\u003eBoard thickness is driven by the U-value you are working to and how much height you have at the abutments, door thresholds and upstands. Measure the available upstand height first: it is the constraint that most often decides the specification on a domestic extension or garden room.\u003c\/p\u003e\u003cp\u003eInsulating under an EPDM roof? Use our \u003ca href=\"\/collections\/roof-kit-calculator\"\u003eroof kit calculator\u003c\/a\u003e to size the membrane, and see \u003ca href=\"\/collections\/termination-bar\"\u003eEPDM termination bars\u003c\/a\u003e for finishing upstands against a wall. Where a build-up needs to breathe, an \u003ca href=\"\/products\/epdm-flat-roof-breather-vent-rubber-roof-uk\"\u003eEPDM flat roof breather vent\u003c\/a\u003e lets trapped moisture out. Full systems are in our \u003ca href=\"\/collections\/rubber-roofing-kits-and-epdm-roof-kits\"\u003eEPDM roof kits\u003c\/a\u003e.\u003c\/p\u003e","products":[{"product_id":"pir-insulation-board-foil-faced-2400-x-1200mm","title":"PIR Insulation Board – Foil-Faced Rigid Board for Warm Roofs, 2400 x 1200mm, 6 Thicknesses","description":"\u003cp\u003eOn a warm roof the insulation sits above the deck and below the waterproofing, which means it does two jobs at once: it carries the thermal performance and it keeps the deck warm enough to stay out of the condensation risk zone.\u003c\/p\u003e\n\u003cp\u003eRigid PIR is the standard board for that build-up because it delivers a given U-value in the least thickness — useful when an extension roof has a fixed height to work to.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eFoil-faced rigid PIR board, 2400 x 1200mm (2.88m² per board)\u003c\/li\u003e\n\u003cli\u003eSix thicknesses from 25mm to 100mm — build up thickness to hit your target U-value\u003c\/li\u003e\n\u003cli\u003eThermal conductivity 0.022 W\/mK\u003c\/li\u003e\n\u003cli\u003eSold as individual boards, so you order exactly what the roof needs\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecification\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eBoard size\u003c\/th\u003e\n\u003ctd\u003e2400 x 1200mm (2.88m² per board)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eThicknesses\u003c\/th\u003e\n\u003ctd\u003e25mm, 30mm, 40mm, 50mm, 75mm, 100mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCore\u003c\/th\u003e\n\u003ctd\u003eRigid polyisocyanurate (PIR)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFacings\u003c\/th\u003e\n\u003ctd\u003eLow-emissivity composite foil, both faces\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eThermal conductivity\u003c\/th\u003e\n\u003ctd\u003e0.022 W\/mK\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eApplications\u003c\/th\u003e\n\u003ctd\u003eWarm flat roof, pitched roof, wall and floor construction\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSupplied as\u003c\/th\u003e\n\u003ctd\u003eSingle boards\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFrequently asked questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eHow many boards do I need?\u003c\/strong\u003e Each board covers 2.88m². Divide your roof area by 2.88 and round up, allowing extra for cuts around upstands and outlets — most roofs waste 5–10% on cutting.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhich thickness should I choose?\u003c\/strong\u003e Thickness is driven by the U-value your project has to meet, so check your building control requirement or specification rather than guessing.\u003c\/p\u003e\n\u003cp\u003eWhere headroom or upstand height is tight, PIR's low conductivity means you reach a target with less depth than most alternatives.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I stack two thinner boards instead of one thick one?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes — laying two layers with staggered joints is common practice and helps reduce thermal bridging through the joints, though it adds a little labour.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it go above or below the deck?\u003c\/strong\u003e For a warm roof, above the deck and below the waterproofing layer, with a vapour control layer beneath the insulation.\u003c\/p\u003e\n\u003cp\u003eInsulating below the deck instead creates a cold roof, which is a different build-up with its own ventilation requirements.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat fire performance does it have?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFire classification varies by manufacturer and board type, so we don't quote a rating here — check the datasheet for the board supplied, or ask us before ordering if your project has a specific fire requirement.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes my roof need a fall built in as well as insulation?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eIf your deck doesn't already fall to the outlets, our \u003ca href=\"\/products\/tapered-pir-roof-insulation-board-flat-roof-drainage-fall-system-3-thickness-bands\"\u003eTapered PIR Roof Insulation Board\u003c\/a\u003e creates that drainage fall at insulation level instead of using this constant-thickness board.\u003c\/p\u003e\n\u003cp\u003eBuilding a warm flat roof?\u003c\/p\u003e\n\u003cp\u003eLay our \u003ca href=\"\/products\/polythene-vapour-control-layer-vcl-4m-x-25m\"\u003epolythene vapour control layer\u003c\/a\u003e beneath these boards, then finish with either our \u003ca href=\"\/products\/flexiproof-epdm-contact-bonding-adhesive\"\u003eEPDM contact bonding adhesive\u003c\/a\u003e-bonded rubber membrane or our \u003ca href=\"\/products\/pvc-single-ply-roofing-membrane\"\u003ePVC single-ply roofing membrane\u003c\/a\u003e as the top waterproofing layer, and finish the perimeter with our \u003ca href=\"\/products\/upvc-gutter-drip-trim-for-epdm-roofs-2-5m\"\u003euPVC gutter drip trim\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003eIf the roof above this insulation is a metal-clad finish rather than a membrane, our \u003ca href=\"\/products\/standing-seam-steel-roofing-sheet\"\u003estanding seam roofing sheet system\u003c\/a\u003e is a suitable concealed-fix covering for the same warm-roof build-up.\u003c\/p\u003e\n\u003cp\u003eIf your build-up needs to breathe rather than seal completely — timber-frame, period or listed reroofs — our \u003ca href=\"\/products\/wood-fibre-sarking-insulation-board-breathable-timber-frame\"\u003ewood fibre sarking \u0026amp; insulation board\u003c\/a\u003e is the vapour-open alternative to this foil-faced PIR.\u003c\/p\u003e","brand":"Rubber Roof UK","offers":[{"title":"25mm","offer_id":46002499092671,"sku":"RRUK-PIR-2412-25","price":50.99,"currency_code":"GBP","in_stock":true},{"title":"30mm","offer_id":46002499125439,"sku":"RRUK-PIR-2412-30","price":54.99,"currency_code":"GBP","in_stock":true},{"title":"40mm","offer_id":46002499158207,"sku":"RRUK-PIR-2412-40","price":62.99,"currency_code":"GBP","in_stock":true},{"title":"50mm","offer_id":46002499190975,"sku":"RRUK-PIR-2412-50","price":76.99,"currency_code":"GBP","in_stock":true},{"title":"75mm","offer_id":46002499223743,"sku":"RRUK-PIR-2412-75","price":98.99,"currency_code":"GBP","in_stock":true},{"title":"100mm","offer_id":46002499256511,"sku":"RRUK-PIR-2412-100","price":110.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0598\/1804\/9727\/files\/pir-insulation-boards-installed-warm-flat-roof.jpg?v=1786480505"},{"product_id":"polythene-vapour-control-layer-vcl-4m-x-25m","title":"Polythene Vapour Control Layer – Virgin Grade VCL for Warm Roofs, 4m x 25m","description":"\u003cp\u003eEvery warm roof needs a vapour control layer under the insulation, and it isn't optional detailing — it's the layer that stops warm, moist air from inside the building reaching the cold side of the build-up and condensing there.\u003c\/p\u003e\n\u003cp\u003eSkip it or lap it badly and the problem shows up years later as a saturated deck.\u003c\/p\u003e\n\u003cp\u003eThis is virgin-grade polythene VCL in a translucent green tint, so you can see your fixing lines through it as you lay.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eVirgin-grade polythene vapour control layer, 4m x 25m roll covering 100m²\u003c\/li\u003e\n\u003cli\u003eTwo gauges: 1000 gauge (250 micron) and heavier-duty 1200 gauge (300 micron)\u003c\/li\u003e\n\u003cli\u003eTranslucent green tint — see through to the deck for accurate fixing\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecification\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eRoll size\u003c\/th\u003e\n\u003ctd\u003e4m x 25m (100m² per roll)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eGauges\u003c\/th\u003e\n\u003ctd\u003e1000 gauge (250 micron), 1200 gauge (300 micron)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eVirgin-grade blown polythene\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eColour\u003c\/th\u003e\n\u003ctd\u003eTranslucent green tint\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003ePosition in build-up\u003c\/th\u003e\n\u003ctd\u003eAbove the deck, beneath the insulation (warm roof)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFrequently asked questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhich gauge should I choose?\u003c\/strong\u003e 1000 gauge is the usual specification for domestic warm roofs.\u003c\/p\u003e\n\u003cp\u003eStep up to 1200 gauge where the membrane will see more foot traffic during the build, or where the specification calls for a heavier-duty layer.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhere exactly does it go?\u003c\/strong\u003e Directly on the deck, beneath the insulation.\u003c\/p\u003e\n\u003cp\u003eThe order is deck, then VCL, then insulation, then waterproofing — that keeps the vapour barrier on the warm side of the insulation, which is the whole point of it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow much do I need?\u003c\/strong\u003e Each roll covers 100m². Allow generous laps at every joint and turn the membrane up at perimeters and upstands, so order comfortably more than the bare roof area.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow are the joints sealed?\u003c\/strong\u003e Lap the sheets and seal the laps with a suitable vapour barrier tape. A VCL only performs if it's continuous, so laps, penetrations and perimeter upstands all need sealing.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs a VCL the same as a breather membrane?\u003c\/strong\u003e No, and they aren't interchangeable. A VCL resists vapour and goes under the insulation on a warm roof.\u003c\/p\u003e\n\u003cp\u003eA breather membrane is designed to let vapour out and belongs in a ventilated pitched roof build-up.\u003c\/p\u003e\n\u003cp\u003eBuilding a warm flat roof? This sits directly beneath our \u003ca href=\"\/products\/pir-insulation-board-foil-faced-2400-x-1200mm\"\u003efoil-faced PIR insulation board\u003c\/a\u003e, with \u003ca href=\"\/products\/1-2mm-epdm-rubber-roofing-membrane\"\u003e1.2mm EPDM membrane\u003c\/a\u003e bonded over the top using our \u003ca href=\"\/products\/flexiproof-epdm-contact-bonding-adhesive\"\u003eEPDM contact bonding adhesive\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003eIf the specification calls for a hot-air-welded, contractor-installed finish instead, our \u003ca href=\"\/products\/pvc-single-ply-roofing-membrane\"\u003ePVC single-ply roofing membrane\u003c\/a\u003e is a suitable alternative top layer over the same VCL and insulation build-up.\u003c\/p\u003e","brand":"Rubber Roof UK","offers":[{"title":"1000 gauge (250 micron)","offer_id":46002508497087,"sku":"RRUK-VCL-POLY-1000G-4X25","price":319.99,"currency_code":"GBP","in_stock":true},{"title":"1200 gauge (300 micron)","offer_id":46002508529855,"sku":"RRUK-VCL-POLY-1200G-4X25","price":362.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0598\/1804\/9727\/files\/polythene-vapour-control-layer-flat-roof-deck.jpg?v=1786480505"},{"product_id":"80mm-pir-insulated-composite-roof-panel","title":"80mm PIR Insulated Roof Panel – Composite Sandwich Sheet, 1000mm Cover, 5 Lengths","description":"\u003cp\u003eSheeting a workshop, garage or agricultural building the traditional way is three separate operations: fix the liner, lay the insulation, then fix the outer sheet over the top.\u003c\/p\u003e\n\u003cp\u003eAn insulated composite panel collapses all three into one.\u003c\/p\u003e\n\u003cp\u003eThe 80mm rigid PIR core is factory-bonded between a ribbed anthracite outer face and a flat steel liner, so a single lift gives you a weathertight roof, the insulation and a finished internal ceiling at the same time.\u003c\/p\u003e\n\u003cp\u003eThese panels are supplied in five stock lengths from 3.075m to 7.075m, each with a 1000mm cover width and a 75mm cutback at the eaves end.\u003c\/p\u003e\n\u003cp\u003eAt 80mm the core gives a U-value of 0.25 W\/m²K — the thickness most people settle on for a heated workshop, a garden studio, a stable block or any building where both heat loss and condensation need dealing with properly rather than patched over.\u003c\/p\u003e\n\u003ch2\u003eCheck your rib spacing before you order\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eThis panel has a 33mm rib at 250mm centres — four ribs across the 1000mm cover width.\u003c\/strong\u003e Several other composite roof panels on the UK market use a three-rib profile at 333mm centres.\u003c\/p\u003e\n\u003cp\u003eThe two are not interchangeable: a 250mm-pitch panel will not line up or lap correctly against a 333mm-pitch roof.\u003c\/p\u003e\n\u003cp\u003eIf you are extending, repairing or matching into an existing composite roof, measure the rib centres on what is already there before ordering.\u003c\/p\u003e\n\u003cp\u003eFor a complete new roof this makes no difference — just order the whole roof in one profile.\u003c\/p\u003e\n\u003ch3\u003eWhere these panels work well\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eWorkshops, garages and home studios where the roof needs to be warm and finished inside without a separate ceiling\u003c\/li\u003e\n\u003cli\u003eAgricultural and equestrian buildings — stables, feed stores, machinery sheds\u003c\/li\u003e\n\u003cli\u003eCommercial units, storage buildings and light industrial roofs\u003c\/li\u003e\n\u003cli\u003eRe-roofing an existing single-skin metal building that suffers from condensation and heat loss\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTechnical specification\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eInsulation core\u003c\/th\u003e\n\u003ctd\u003eRigid PIR, approximately 40 kg\/m³\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCore thickness\u003c\/th\u003e\n\u003ctd\u003e80mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eU-value\u003c\/th\u003e\n\u003ctd\u003e0.25 W\/m²K\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCover width\u003c\/th\u003e\n\u003ctd\u003e1000mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eOuter face\u003c\/th\u003e\n\u003ctd\u003e0.5mm profiled steel, anthracite polyester paint finish\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eLiner face\u003c\/th\u003e\n\u003ctd\u003e0.5mm flat steel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eRib height\u003c\/th\u003e\n\u003ctd\u003e33mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eRib spacing\u003c\/th\u003e\n\u003ctd\u003e250mm centres (4 ribs per panel width)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eEaves cutback\u003c\/th\u003e\n\u003ctd\u003e75mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMinimum roof pitch\u003c\/th\u003e\n\u003ctd\u003e4° after deflection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eStock lengths\u003c\/th\u003e\n\u003ctd\u003e3.075m, 4.075m, 5.075m, 6.075m, 7.075m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSold as\u003c\/th\u003e\n\u003ctd\u003eIndividual panels — order the quantity you need\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFrequently asked questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eHow many panels do I need?\u003c\/strong\u003e\u003cbr\u003eDivide the width of your roof slope by 1.0m — the cover width — and round up.\u003c\/p\u003e\n\u003cp\u003eThen pick the length that spans from ridge to eaves in one piece if you can; a single unbroken panel is always a better roof than two panels with an end lap in the middle.\u003c\/p\u003e\n\u003cp\u003eOrder one spare if the roof is an awkward shape.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the 75mm cutback for?\u003c\/strong\u003e\u003cbr\u003eAt one end of the panel the insulation core and the steel liner are trimmed back 75mm, leaving the outer sheet projecting on its own.\u003c\/p\u003e\n\u003cp\u003eThat projecting lip is what oversails the gutter at the eaves, so rainwater discharges into the gutter rather than tracking back into the panel end.\u003c\/p\u003e\n\u003cp\u003eFit the cutback end at the eaves, not at the ridge.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I lay these at a lower pitch than 4°?\u003c\/strong\u003e\u003cbr\u003eNo.\u003c\/p\u003e\n\u003cp\u003e4° is the minimum \u003cem\u003eafter deflection\u003c\/em\u003e, which means the roof needs to still be at 4° once the panels have taken up their loaded position under their own weight, snow and any foot traffic.\u003c\/p\u003e\n\u003cp\u003eOn long spans that usually means designing to a steeper nominal pitch so you still have 4° left when it settles. Below that, water sits on the laps instead of running off them.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDo I still need insulation and a vapour control layer underneath?\u003c\/strong\u003e\u003cbr\u003eNo — the panel is the entire roof build-up in one component, and that is the point of it.\u003c\/p\u003e\n\u003cp\u003eWhat still needs attention is the junctions: eaves, ridge, verges and any penetrations need correctly detailed flashings and fillers, because that is where air and moisture will find their way in if the detailing is rushed.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow are the panels fixed down?\u003c\/strong\u003e\u003cbr\u003eThey are through-fixed into purlins with composite panel fixings long enough to pass through the full 80mm depth and bite into the steel or timber below, with sealing washers.\u003c\/p\u003e\n\u003cp\u003eFixings are not supplied with the panels — the correct length depends on your purlin type, so order them once you know what you are fixing into.\u003c\/p\u003e\n\u003ch3\u003eWhat else you will need\u003c\/h3\u003e\n\u003cp\u003ePanels arriving on a building that also needs plain sheeting, drainage or edge protection pair naturally with the rest of our industrial roofing range:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/rubberroofuk.uk\/products\/box-profile-steel-roofing-sheets-32-1000-cut-to-length\"\u003eBox Profile Steel Roofing Sheets 32\/1000\u003c\/a\u003e — single-skin sheeting for lean-tos, porches and unheated sections of the same building\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/rubberroofuk.uk\/products\/pir-insulation-board-foil-faced-2400-x-1200mm\"\u003eFoil-Faced PIR Insulation Board\u003c\/a\u003e — for flat roof and warm deck areas where a composite panel is not appropriate\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/rubberroofuk.uk\/products\/aluminium-half-round-gutter-system-125mm\"\u003eAluminium Half Round Gutter System 125mm\u003c\/a\u003e — to take the discharge at the eaves\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/rubberroofuk.uk\/products\/roof-edge-protection-guardrail-kit\"\u003eFreestanding Roof Edge Protection Guardrail Kit\u003c\/a\u003e — non-penetrating edge protection while the roof is being sheeted\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eNot sure which length suits your span, or whether your existing roof is a 250mm or 333mm rib pitch? Send us the rib measurement and the slope length and we will tell you what fits.\u003c\/p\u003e","brand":"Rubber Roof UK","offers":[{"title":"3.075m","offer_id":46081626210495,"sku":"RRUK-IRP80-3075","price":255.0,"currency_code":"GBP","in_stock":true},{"title":"4.075m","offer_id":46081626243263,"sku":"RRUK-IRP80-4075","price":339.0,"currency_code":"GBP","in_stock":true},{"title":"5.075m","offer_id":46081626276031,"sku":"RRUK-IRP80-5075","price":419.0,"currency_code":"GBP","in_stock":true},{"title":"6.075m","offer_id":46081626308799,"sku":"RRUK-IRP80-6075","price":499.0,"currency_code":"GBP","in_stock":true},{"title":"7.075m","offer_id":46081626341567,"sku":"RRUK-IRP80-7075","price":585.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0598\/1804\/9727\/files\/80mm-pir-insulated-roof-panel-anthracite-workshop-roof-installed.jpg?v=1787570925"},{"product_id":"wood-fibre-sarking-insulation-board-breathable-timber-frame","title":"Wood Fibre Sarking \u0026amp; Insulation Board – Breathable Timber-Frame Roof Board, 3 Thicknesses","description":"\u003cp\u003eFoam insulation boards do one job well: they stop heat escaping. What they don't do is let a roof breathe — trap the wrong kind of moisture behind a foil-faced PIR board on a timber-frame or period building and it has nowhere to go. Wood fibre board is the answer roofers reach for on breathable build-ups: a rigid board pressed from compressed softwood fibre, vapour-open enough to let a roof structure dry out in both directions while still doing genuine insulating and wind-bracing work.\u003c\/p\u003e\n\n\u003cp\u003eWe stock it in two distinct roles. The 22mm board is a racking and sarking board — fixed straight across rafters as a breathable alternative to OSB or plywood sarking, giving the roof structure rigidity and wind resistance before the counter-battens and covering go on. The 80mm and 100mm boards are the insulation-grade version of the same material, used where a genuinely vapour-permeable insulation layer matters more than squeezing the last millimetre of thickness out of a warm roof build-up — timber-frame extensions, listed and period reroofs, and anywhere the design calls for a breathing roof rather than a sealed one.\u003c\/p\u003e\n\n\u003ch3\u003eKey benefits\u003c\/h3\u003e\n\u003cp\u003eVapour-permeable — lets moisture pass through and disperse rather than trapping it against timber. Hygroscopic — the fibre structure buffers and releases moisture vapour, which helps manage condensation risk in breathable constructions. Tongue-and-groove long edges on every board for a tight, draught-resistant joint without extra tape. Genuine wind-bracing value on the 22mm sarking board when fixed correctly across rafters. Natural, largely bio-based material for anyone specifying toward a lower-impact build-up.\u003c\/p\u003e\n\n\u003ch3\u003eSuitable applications\u003c\/h3\u003e\n\u003cp\u003ePitched roof sarking\/racking under tiles, slates or shingles on timber-frame construction. Warm roof and rafter-level insulation on breathable build-ups where PIR isn't the right fit. Period and listed-building reroofs where the original structure needs to keep breathing. Companion insulation layer alongside our \u003ca href=\"https:\/\/rubberroofuk.uk\/products\/breathable-roofing-membrane-125gsm-roof-wall-underlay\"\u003ebreathable roofing membrane\u003c\/a\u003e, which is the vapour-permeable underlay this board is designed to work with.\u003c\/p\u003e\n\n\u003ch3\u003eSpecification\u003c\/h3\u003e\n\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eVariant\u003c\/th\u003e\n\u003cth\u003eBoard size\u003c\/th\u003e\n\u003cth\u003eCoverage per board\u003c\/th\u003e\n\u003cth\u003eRole\u003c\/th\u003e\n\u003cth\u003eEdge detail\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e22mm Sarking Board\u003c\/td\u003e\n\u003ctd\u003e2230 x 600mm\u003c\/td\u003e\n\u003ctd\u003e≈1.34m²\u003c\/td\u003e\n\u003ctd\u003eRacking\/sarking board (wind bracing, breathable roof deck)\u003c\/td\u003e\n\u003ctd\u003eTongue \u0026amp; groove\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e80mm Insulation Board\u003c\/td\u003e\n\u003ctd\u003e2230 x 600mm\u003c\/td\u003e\n\u003ctd\u003e≈1.34m²\u003c\/td\u003e\n\u003ctd\u003eRafter-level insulation, breathable build-up\u003c\/td\u003e\n\u003ctd\u003eTongue \u0026amp; groove\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e100mm Insulation Board\u003c\/td\u003e\n\u003ctd\u003e2230 x 600mm\u003c\/td\u003e\n\u003ctd\u003e≈1.34m²\u003c\/td\u003e\n\u003ctd\u003eHigher-thickness rafter-level insulation\u003c\/td\u003e\n\u003ctd\u003eTongue \u0026amp; groove\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eInstallation \u0026amp; ordering guidance\u003c\/h3\u003e\n\u003cp\u003eFix across rafters with the tongue-and-groove edges engaged, following your roofing contractor's or the manufacturer's datasheet for fixing centres and counter-batten detail — this varies with rafter spacing and roof pitch, so we don't state a single fixing pattern here. Keep boards dry and off wet ground until they're covered; like any wood-based board, prolonged exposure to standing water before installation isn't good for it. Pair the 22mm sarking board with our \u003ca href=\"https:\/\/rubberroofuk.uk\/products\/breathable-roofing-membrane-125gsm-roof-wall-underlay\"\u003ebreathable roofing membrane\u003c\/a\u003e over the top, and see our \u003ca href=\"https:\/\/rubberroofuk.uk\/products\/pir-insulation-board-foil-faced-2400-x-1200mm\"\u003ePIR insulation board\u003c\/a\u003e if your build-up calls for a sealed, foil-faced warm-roof board instead of a breathable one — they solve different problems and it's worth checking which one your design actually needs before ordering.\u003c\/p\u003e\n\n\u003ch3\u003eFAQs\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhat's actually different between the 22mm board and the 80\/100mm boards?\u003c\/strong\u003e The 22mm is a thin racking\/sarking board — its job is structural bracing and breathability under the roof covering, not meaningful insulation value. The 80mm and 100mm boards are the insulation-grade version of the same wood fibre material, thick enough to contribute real thermal performance in a breathable build-up.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eShould I use this instead of your PIR insulation board?\u003c\/strong\u003e Not automatically. PIR is the simpler, higher-performance-per-millimetre choice for a standard sealed warm roof. Wood fibre earns its place specifically where the design needs to breathe — timber-frame, period or listed work, or anywhere a vapour-open build-up is specified. If you're not sure which your roof needs, that's worth checking with whoever specified the build-up before you order.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it need to be protected once fixed?\u003c\/strong\u003e Yes — like any wood-fibre or timber board, it should be covered by the roofing membrane and covering within a reasonable window and not left exposed to prolonged wet weather.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat fixings should I use?\u003c\/strong\u003e Standard roofing screws or nails sized for the board thickness and your batten\/counter-batten detail; we don't sell a proprietary fixing kit for this board, so use fixings rated for the load and spacing your roof design specifies.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow quickly does this dispatch?\u003c\/strong\u003e The 22mm and 80mm boards are quick-turnaround stock items. The 100mm board is a lower-volume line with a longer lead time — please allow around 4–5 weeks for that thickness specifically, and order early if it's on your critical path.\u003c\/p\u003e\n\n\u003cp\u003e\u003cem\u003eCustom, unbranded product — see our \u003ca href=\"https:\/\/rubberroofuk.uk\/products\/breathable-roofing-membrane-125gsm-roof-wall-underlay\"\u003ebreathable roofing membrane\u003c\/a\u003e and \u003ca href=\"https:\/\/rubberroofuk.uk\/products\/pir-insulation-board-foil-faced-2400-x-1200mm\"\u003ePIR insulation board\u003c\/a\u003e for the companion products most often ordered alongside this one.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003eSpecifying a breathable sarking board beneath western red cedar shingles? See our \u003ca href=\"https:\/\/rubberroofuk.uk\/products\/western-red-cedar-roof-shingles-no-1-blue-label-grade-2-49m-pack\"\u003ewestern red cedar roof shingles\u003c\/a\u003e, a natural timber roof covering that pairs well with this breathable board.\u003c\/p\u003e","brand":"Rubber Roof UK","offers":[{"title":"22mm Sarking Board","offer_id":46139697070271,"sku":"RRUK-WFB-22MM","price":29.99,"currency_code":"GBP","in_stock":true},{"title":"80mm Insulation Board","offer_id":46139697103039,"sku":"RRUK-WFB-80MM","price":84.99,"currency_code":"GBP","in_stock":true},{"title":"100mm Insulation Board","offer_id":46139697135807,"sku":"RRUK-WFB-100MM","price":109.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0598\/1804\/9727\/files\/wood-fibre-sarking-board-installed-roof-rafters-58fcc980-a114-41e2-915a-081316f20a44.jpg?v=1788509365"}],"url":"https:\/\/rubberroofuk.uk\/collections\/roof-insulation.oembed","provider":"Rubber Roof UK","version":"1.0","type":"link"}