{"product_id":"20mm-storage-drainage-membrane-2m-x-10m","title":"UGR 20mm Storage \u0026 Drainage Membrane 2m x 10m","description":"\u003ch6\u003eDescription\u003c\/h6\u003e\n\u003ch2\u003eDrain, store and filter water in one layer\u003c\/h2\u003e\n\u003cp\u003eUGR 20mm Storage \u0026amp; Drainage Membrane is an all-in-one water-management layer for extensive and intensive green roofs.\u003c\/p\u003e\n\u003cp\u003eManufactured from recycled high-density polyethylene, its 20mm-deep studded cavities temporarily store rainwater to support healthy vegetation. Perforations within the membrane allow excess water to drain into the space below, helping prevent the growing medium and plant roots from becoming saturated.\u003c\/p\u003e\n\u003cp\u003eA high-quality geotextile filter layer is permanently bonded to the upper face. This prevents soil fines and growing medium from blocking the drainage cavities while also removing the need to install a separate loose filter fabric.\u003c\/p\u003e\n\u003ch2\u003eWhy water management matters\u003c\/h2\u003e\n\u003cp\u003eA successful green roof needs to retain useful moisture while allowing excess rainfall to drain away safely.\u003c\/p\u003e\n\u003cp\u003eUGR 20mm Storage \u0026amp; Drainage Membrane performs three important functions:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cb\u003eWater storage:\u003c\/b\u003e Holds approximately 6 litres of water per square metre for use by the vegetation\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eDrainage:\u003c\/b\u003e Allows excess water to pass through the perforated membrane\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eFiltration:\u003c\/b\u003e Prevents soil and fine particles from obstructing the drainage cavities\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe bonded geotextile also helps prevent the filter layer from slipping or compressing into the storage cups during installation.\u003c\/p\u003e\n\u003ch2\u003eSuitable green roof applications\u003c\/h2\u003e\n\u003cp\u003eUGR 20mm Storage \u0026amp; Drainage Membrane can be specified for:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eExtensive green roofs with low-growing vegetation\u003c\/li\u003e\n\u003cli\u003eSemi-intensive green roof systems\u003c\/li\u003e\n\u003cli\u003eIntensive green roofs with deeper growing substrates\u003c\/li\u003e\n\u003cli\u003eFlat roofs and low-pitched roofs\u003c\/li\u003e\n\u003cli\u003eHouses and residential extensions\u003c\/li\u003e\n\u003cli\u003eGarages, sheds and garden buildings\u003c\/li\u003e\n\u003cli\u003eLarger commercial green roofs\u003c\/li\u003e\n\u003cli\u003eSoft landscaping over decks\u003c\/li\u003e\n\u003cli\u003eInverted warm roof applications\u003c\/li\u003e\n\u003cli\u003eSuitable walkable or drivable landscaping build-ups\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eIts combination of drainage, storage and filtration makes it a versatile option for a broad range of domestic and professional green roof projects.\u003c\/p\u003e\n\u003cp\u003eFor walkable or drivable finishes, the bonded geotextile must be removed, the studs must be filled and the appropriate bedding or sub-base courses installed as part of the specified system.\u003c\/p\u003e\n\u003ch2\u003eStrong, durable and long-lasting\u003c\/h2\u003e\n\u003cp\u003eUGR 20mm Storage \u0026amp; Drainage Membrane has an approximate compressive strength of 150kN\/m², helping it withstand the loads applied by the green roof build-up above.\u003c\/p\u003e\n\u003cp\u003eThe recycled HDPE membrane is:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eTough and durable\u003c\/li\u003e\n\u003cli\u003eResistant to water\u003c\/li\u003e\n\u003cli\u003eResistant to alkalis and saline solutions\u003c\/li\u003e\n\u003cli\u003eResistant to organic acids\u003c\/li\u003e\n\u003cli\u003eUnaffected by minerals\u003c\/li\u003e\n\u003cli\u003eResistant to bacteria, fungi and other small organisms\u003c\/li\u003e\n\u003cli\u003eSuitable for temperatures between -30°C and +80°C\u003c\/li\u003e\n\u003cli\u003eGuaranteed against deterioration for 30 years\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe product is also tested and CE marked to the relevant standard.\u003c\/p\u003e\n\u003ch2\u003eWhere UGR 20mm Membrane fits in the system\u003c\/h2\u003e\n\u003cp\u003eA typical green roof build-up may include:\u003c\/p\u003e\n\u003col start=\"1\"\u003e\n\u003cli\u003eStructural roof deck\u003c\/li\u003e\n\u003cli\u003ePrimary waterproofing layer\u003c\/li\u003e\n\u003cli\u003eRoot barrier\u003c\/li\u003e\n\u003cli\u003eProtection fleece\u003c\/li\u003e\n\u003cli\u003eUGR 20mm Storage \u0026amp; Drainage Membrane\u003c\/li\u003e\n\u003cli\u003eBonded geotextile filter layer\u003c\/li\u003e\n\u003cli\u003eGreen roof substrate\u003c\/li\u003e\n\u003cli\u003eVegetation\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003eWhere a dedicated root-protection layer is required, install the \u003ca href=\"https:\/\/urbangreenroofs.com\/products\/green-roof-root-barrier\"\u003eUGR Green Roof Root Barrier\u003c\/a\u003e beneath the drainage membrane.\u003c\/p\u003e\n\u003cp\u003eA protection fleece may also be specified to reduce the risk of light mechanical damage to the waterproofing and root barrier. Consider using \u003ca href=\"https:\/\/urbangreenroofs.com\/products\/green-roof-protection-fleece-300\"\u003eUGR Green Roof Protection Fleece 300\u003c\/a\u003e.\u003cbr\u003e\u003c\/p\u003e\n\u003ch2\u003eInstalling UGR 20mm Membrane\u003c\/h2\u003e\n\u003cp\u003eThe application surface should have a gradient of at least 2%. Complete the horizontal waterproofing and install any other specified underlying layers before laying the membrane.\u003c\/p\u003e\n\u003col start=\"1\"\u003e\n\u003cli\u003eRoll out UGR 20mm Storage \u0026amp; Drainage Membrane over the prepared surface with the bonded geotextile facing upwards.\u003c\/li\u003e\n\u003cli\u003eCut the dimpled sheet to the required length, taking care not to damage the waterproofing or any underlying layers.\u003c\/li\u003e\n\u003cli\u003eOverlap adjoining rolls by approximately 100mm.\u003c\/li\u003e\n\u003cli\u003eLift the loose geotextile overlap and position it over the adjoining section.\u003c\/li\u003e\n\u003cli\u003eWhere the joint needs additional protection, seal it using an appropriate compatible jointing tape or sealant.\u003c\/li\u003e\n\u003cli\u003eOnce installed, the membrane can immediately receive the specified extensive or intensive green roof substrate.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003eThe membrane is supplied in a manageable 20m² roll and is installed by simply unrolling and cutting it to fit the roof layout.\u003c\/p\u003e\n\u003ch2\u003eImportant suitability note\u003c\/h2\u003e\n\u003cp\u003eUGR 20mm Storage \u0026amp; Drainage Membrane is not a primary waterproofing membrane or a substitute for dedicated root protection. Where roots could affect the waterproofing or roof structure, install the \u003ca href=\"https:\/\/urbangreenroofs.com\/products\/green-roof-root-barrier\"\u003eUGR Green Roof Root Barrier\u003c\/a\u003e beneath it.\u003c\/p\u003e\n\u003ch6\u003eSpecifications\u003c\/h6\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse;\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Material\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Recycled high-density polyethylene\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Membrane weight\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 1,000g\/m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Geotextile\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Polypropylene, approx. 100g\/m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Total weight\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 1,100g\/m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Stud height\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 20mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Number of studs\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e 400\/m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Colour\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Black\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Roll dimensions\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e 2m x 10m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Geotextile overlap\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Additional 100mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Coverage\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e 20m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Approximate roll weight\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e 22kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Water-storage capacity\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 6l\/m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Water-drainage capacity\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 9l\/(s·m)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Air volume between studs\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 14l\/m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Compressive strength\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 150kN\/m²\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Temperature resistance\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e -30°C to +80°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Characteristic opening width\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 170μm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Water permeability\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Approx. 100 × 10⁻³m\/s to EN ISO 11058\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Fire resistance\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Class E\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Chemical properties\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Chemically resistant\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Additional properties\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Safe for drinking-water contact\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; padding: 6px 12px 6px 0; vertical-align: top;\"\u003e Accreditation\u003c\/th\u003e\n\u003ctd style=\"padding: 6px 0;\"\u003e Tested and CE marked to the relevant standard\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch6\u003eFAQs\u003c\/h6\u003e\n\u003ch4\u003eHow much water does UGR 20mm Membrane store?\u003c\/h4\u003e\n\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003eIts 20mm cavities provide an approximate water-storage capacity of 6 litres per square metre. Excess water can pass through the perforated membrane into the drainage space beneath.\u003c\/p\u003e\n\u003ch4\u003eWhich way up should the membrane be installed?\u003c\/h4\u003e\n\u003cp\u003eInstall it with the bonded geotextile layer facing upwards, towards the growing substrate. The studded HDPE membrane sits beneath the geotextile.\u003c\/p\u003e\n\u003ch4\u003eDoes UGR 20mm Membrane need a separate filter layer?\u003c\/h4\u003e\n\u003cp\u003eNo separate loose filter fabric is normally required directly above the membrane because a polypropylene geotextile filter layer is already bonded to it.\u003c\/p\u003e\n\u003ch4\u003eCan it be used for both extensive and intensive green roofs?\u003c\/h4\u003e\n\u003cp\u003eYes. UGR 20mm Storage \u0026amp; Drainage Membrane is suitable for extensive, semi-intensive and intensive green roofs, subject to the overall system design, structural loading and planting requirements.\u003c\/p\u003e\n\u003ch6\u003eHelp\u003c\/h6\u003e\n\u003ch2\u003eNeed help choosing your drainage layer?\u003c\/h2\u003e\n\u003cp\u003eNot sure whether the UGR 20mm Storage \u0026amp; Drainage Membrane offers the right balance of water storage and drainage for your planting scheme, roof pitch or substrate depth? Our in-house technical team can provide free, practical advice on selecting compatible layers for your green roof.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eEmail:\u003c\/strong\u003e \u003ca href=\"mailto:info@urbangreenroofs.com\" title=\"mailto:info@urbangreenroofs.com\"\u003einfo@urbangreenroofs.com\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eTelephone:\u003c\/strong\u003e \u003ca href=\"tel:+44%20117%20370%204018\" title=\"tel:+44 117 370 4018\"\u003e+44 117 370 4018\u003c\/a\u003e\u003c\/p\u003e","brand":"Urban Green Roofs","offers":[{"title":"Default Title","offer_id":54207514575191,"sku":"UGR20SDM20","price":202.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0954\/0150\/9207\/files\/PermaSEAL_PRO_20P_Final_Image_1000x1000_edited.jpg?v=1788431828","url":"https:\/\/urbangreenroofs.com\/products\/20mm-storage-drainage-membrane-2m-x-10m","provider":"Urban Green Roofs","version":"1.0","type":"link"}