{"product_id":"cm20-cavity-drain-membrane-for-basements-2m-x-20m-yellow-hi-vis","title":"CM20 Cavity Drain Membrane for Basements 2m X 20m YELLOW (Hi Vis)","description":"\u003ch2 data-end=\"89\" data-start=\"0\" data-section-id=\"896bty\"\u003eClever Shield CM20 Cavity Drain Membrane – High Capacity Type C Basement Waterproofing\u003c\/h2\u003e\n\u003cp data-end=\"284\" data-start=\"91\"\u003eTake control of heavy water ingress with the \u003cstrong data-end=\"180\" data-start=\"136\"\u003eClever Shield CM20 Cavity Drain Membrane\u003c\/strong\u003e — a \u003cstrong data-end=\"232\" data-start=\"185\"\u003ehigh-capacity Type C waterproofing membrane\u003c\/strong\u003e engineered for demanding below-ground environments.\u003c\/p\u003e\n\u003cp data-end=\"533\" data-start=\"286\"\u003eWith a \u003cstrong data-end=\"348\" data-start=\"293\"\u003e20mm stud profile and superior drainage performance\u003c\/strong\u003e, CM20 delivers reliable protection for basements, floors, and structures exposed to high groundwater levels—helping you achieve a \u003cstrong data-end=\"511\" data-start=\"479\"\u003eGrade 3 dry, habitable space\u003c\/strong\u003e in line with BS 8102.\u003c\/p\u003e\n\u003chr data-end=\"538\" data-start=\"535\"\u003e\n\u003ch3 data-end=\"581\" data-start=\"540\" data-section-id=\"zbz2fq\"\u003eMaximum Drainage. Maximum Protection.\u003c\/h3\u003e\n\u003cul data-end=\"1210\" data-start=\"583\"\u003e\n\u003cli data-end=\"654\" data-start=\"583\" data-section-id=\"yngh88\"\u003e\n\u003cstrong data-end=\"616\" data-start=\"585\"\u003eType C Waterproofing System\u003c\/strong\u003e – Fully compliant with BS 8102:2009\u003c\/li\u003e\n\u003cli data-end=\"728\" data-start=\"655\" data-section-id=\"138hxpx\"\u003e\n\u003cstrong data-end=\"692\" data-start=\"657\"\u003eHigh Drainage Capacity (14L\/m²)\u003c\/strong\u003e – One of the highest in its class\u003c\/li\u003e\n\u003cli data-end=\"812\" data-start=\"729\" data-section-id=\"ammp5i\"\u003e\n\u003cstrong data-end=\"758\" data-start=\"731\"\u003eBBA Certified (18\/5595)\u003c\/strong\u003e – Independently tested for performance \u0026amp; durability\u003c\/li\u003e\n\u003cli data-end=\"899\" data-start=\"813\" data-section-id=\"18rf9ae\"\u003e\n\u003cstrong data-end=\"846\" data-start=\"815\"\u003eIdeal for High Water Tables\u003c\/strong\u003e – Designed for challenging below-ground conditions\u003c\/li\u003e\n\u003cli data-end=\"973\" data-start=\"900\" data-section-id=\"q3yht7\"\u003e\n\u003cstrong data-end=\"923\" data-start=\"902\"\u003eFast Installation\u003c\/strong\u003e – Lightweight rolls for quick floor application\u003c\/li\u003e\n\u003cli data-end=\"1049\" data-start=\"974\" data-section-id=\"tfmx9i\"\u003e\n\u003cstrong data-end=\"1005\" data-start=\"976\"\u003eMinimal Structural Impact\u003c\/strong\u003e – No major prep or invasive work required\u003c\/li\u003e\n\u003cli data-end=\"1135\" data-start=\"1050\" data-section-id=\"48e0wo\"\u003e\n\u003cstrong data-end=\"1076\" data-start=\"1052\"\u003eLong-Term Durability\u003c\/strong\u003e – Resistant to water, salts, roots \u0026amp; structural movement\u003c\/li\u003e\n\u003cli data-end=\"1210\" data-start=\"1136\" data-section-id=\"1idpm2w\"\u003e\n\u003cstrong data-end=\"1163\" data-start=\"1138\"\u003eTemperature Resistant\u003c\/strong\u003e – Performs in both hot and cold environments\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-end=\"1215\" data-start=\"1212\"\u003e\n\u003ch3 data-end=\"1263\" data-start=\"1217\" data-section-id=\"8cavt7\"\u003eBuilt for Demanding Waterproofing Projects\u003c\/h3\u003e\n\u003cp data-end=\"1460\" data-start=\"1265\"\u003eThe CM20 membrane creates a \u003cstrong data-end=\"1324\" data-start=\"1293\"\u003ehigh-capacity drainage void\u003c\/strong\u003e, allowing water to flow freely into \u003cstrong data-end=\"1404\" data-start=\"1361\"\u003edrainage channels and sump pump systems\u003c\/strong\u003e, preventing pressure build-up against floors and walls.\u003c\/p\u003e\n\u003cp data-end=\"1474\" data-start=\"1462\"\u003ePerfect for:\u003c\/p\u003e\n\u003cul data-end=\"1704\" data-start=\"1475\"\u003e\n\u003cli data-end=\"1512\" data-start=\"1475\" data-section-id=\"1dk369s\"\u003eBasement and cellar waterproofing\u003c\/li\u003e\n\u003cli data-end=\"1544\" data-start=\"1513\" data-section-id=\"ww3h2v\"\u003eFloor waterproofing systems\u003c\/li\u003e\n\u003cli data-end=\"1578\" data-start=\"1545\" data-section-id=\"g8mux7\"\u003eHigh water table environments\u003c\/li\u003e\n\u003cli data-end=\"1623\" data-start=\"1579\" data-section-id=\"1h6efbv\"\u003eTunnels, vaults \u0026amp; underground structures\u003c\/li\u003e\n\u003cli data-end=\"1665\" data-start=\"1624\" data-section-id=\"1idsdgj\"\u003eRadon barrier compliant installations\u003c\/li\u003e\n\u003cli data-end=\"1704\" data-start=\"1666\" data-section-id=\"1ols01c\"\u003eNew build \u0026amp; retrofit waterproofing\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-end=\"1709\" data-start=\"1706\"\u003e\n\u003ch3 data-end=\"1737\" data-start=\"1711\" data-section-id=\"1dqbs77\"\u003eProduct Specifications\u003c\/h3\u003e\n\u003cul data-end=\"2005\" data-start=\"1739\"\u003e\n\u003cli data-end=\"1764\" data-start=\"1739\" data-section-id=\"fsnyl5\"\u003e\n\u003cstrong data-end=\"1757\" data-start=\"1741\"\u003eStud Height:\u003c\/strong\u003e 20mm\u003c\/li\u003e\n\u003cli data-end=\"1806\" data-start=\"1765\" data-section-id=\"1dqjlzb\"\u003e\n\u003cstrong data-end=\"1791\" data-start=\"1767\"\u003eWater Void Capacity:\u003c\/strong\u003e 14 litres\/m²\u003c\/li\u003e\n\u003cli data-end=\"1857\" data-start=\"1807\" data-section-id=\"1mflrqq\"\u003e\n\u003cstrong data-end=\"1822\" data-start=\"1809\"\u003eMaterial:\u003c\/strong\u003e High-density polyethylene (HDPE)\u003c\/li\u003e\n\u003cli data-end=\"1954\" data-start=\"1858\" data-section-id=\"19pelyc\"\u003e\n\u003cstrong data-end=\"1875\" data-start=\"1860\"\u003eRoll Sizes:\u003c\/strong\u003e\n\u003cul data-end=\"1954\" data-start=\"1880\"\u003e\n\u003cli data-end=\"1908\" data-start=\"1880\" data-section-id=\"1t2v9sk\"\u003e2m x 20m (40m² coverage)\u003c\/li\u003e\n\u003cli data-end=\"1954\" data-start=\"1911\" data-section-id=\"3dddqh\"\u003e2m x 10m (20m² coverage | approx. 20kg)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli data-end=\"2005\" data-start=\"1955\" data-section-id=\"91jcrb\"\u003e\n\u003cstrong data-end=\"1973\" data-start=\"1957\"\u003eApplication:\u003c\/strong\u003e Floors \u0026amp; walls (below ground)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-end=\"2010\" data-start=\"2007\"\u003e\n\u003ch3 data-end=\"2059\" data-start=\"2012\" data-section-id=\"1uiyn5s\"\u003eDesigned for Complete Waterproofing Systems\u003c\/h3\u003e\n\u003cp data-end=\"2140\" data-start=\"2061\"\u003eFor best results, install CM20 as part of a full cavity drain system including:\u003c\/p\u003e\n\u003cul data-end=\"2276\" data-start=\"2142\"\u003e\n\u003cli data-end=\"2173\" data-start=\"2142\" data-section-id=\"1szzmfi\"\u003ePerimeter drainage channels\u003c\/li\u003e\n\u003cli data-end=\"2206\" data-start=\"2174\" data-section-id=\"m14vmi\"\u003eSump chambers \u0026amp; pump systems\u003c\/li\u003e\n\u003cli data-end=\"2239\" data-start=\"2207\" data-section-id=\"1l0o7nw\"\u003eFixing plugs \u0026amp; sealing tapes\u003c\/li\u003e\n\u003cli data-end=\"2276\" data-start=\"2240\" data-section-id=\"1qgsed4\"\u003eFloor finishes or screed systems\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-end=\"2377\" data-start=\"2278\"\u003eThis ensures a \u003cstrong data-end=\"2343\" data-start=\"2293\"\u003emaintainable, long-term waterproofing solution\u003c\/strong\u003e that meets UK building standards.\u003c\/p\u003e\n\u003chr data-end=\"2382\" data-start=\"2379\"\u003e\n\u003ch3 data-end=\"2423\" data-start=\"2384\" data-section-id=\"19prnub\"\u003eIdeal for Converting Problem Spaces\u003c\/h3\u003e\n\u003cp data-end=\"2593\" data-start=\"2425\"\u003eWhether you're tackling a flooded basement or planning a full conversion, CM20 helps you create \u003cstrong data-end=\"2561\" data-start=\"2521\"\u003edry, usable living or storage spaces\u003c\/strong\u003e—even in high-risk environments.\u003c\/p\u003e\n\u003chr data-end=\"2598\" data-start=\"2595\"\u003e\n\u003ch2 data-end=\"2629\" data-start=\"2600\" data-section-id=\"1r8frcv\"\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3 data-end=\"2674\" data-start=\"2631\" data-section-id=\"112bh4c\"\u003eWhat is a Type C cavity drain membrane?\u003c\/h3\u003e\n\u003cp data-end=\"2806\" data-start=\"2675\"\u003eA Type C membrane manages water ingress by allowing it to enter a controlled cavity and safely drain away, rather than blocking it.\u003c\/p\u003e\n\u003ch3 data-end=\"2839\" data-start=\"2808\" data-section-id=\"s7iy4e\"\u003eWhy choose a 20mm membrane?\u003c\/h3\u003e\n\u003cp data-end=\"2964\" data-start=\"2840\"\u003eA 20mm stud depth provides \u003cstrong data-end=\"2896\" data-start=\"2867\"\u003egreater drainage capacity\u003c\/strong\u003e, making it ideal for areas with \u003cstrong data-end=\"2963\" data-start=\"2929\"\u003ehigh water ingress or pressure\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch3 data-end=\"3006\" data-start=\"2966\" data-section-id=\"ii4q8t\"\u003eIs Clever Shield CM20 BBA certified?\u003c\/h3\u003e\n\u003cp data-end=\"3107\" data-start=\"3007\"\u003eYes, CM20 is fully \u003cstrong data-end=\"3053\" data-start=\"3026\"\u003eBBA certified (18\/5595)\u003c\/strong\u003e, ensuring compliance with UK waterproofing standards.\u003c\/p\u003e\n\u003ch3 data-end=\"3140\" data-start=\"3109\" data-section-id=\"1uw5c9l\"\u003eCan this be used on floors?\u003c\/h3\u003e\n\u003cp data-end=\"3252\" data-start=\"3141\"\u003eYes, CM20 is specifically designed for \u003cstrong data-end=\"3202\" data-start=\"3180\"\u003efloor applications\u003c\/strong\u003e and can also be used on walls in high-risk areas.\u003c\/p\u003e\n\u003ch3 data-end=\"3298\" data-start=\"3254\" data-section-id=\"5mrqs8\"\u003eIs it suitable for basement conversions?\u003c\/h3\u003e\n\u003cp data-end=\"3405\" data-start=\"3299\"\u003eAbsolutely. It’s ideal for creating \u003cstrong data-end=\"3369\" data-start=\"3335\"\u003edry, habitable basement spaces\u003c\/strong\u003e when used as part of a full system.\u003c\/p\u003e\n\u003ch5\u003eBBA\u003cbr\u003e\n\u003c\/h5\u003e\n\u003cp\u003e\u003ca aria-label=\"Visit a webpage about Cm20 bba\" title=\"Cm20 bba\" href=\"https:\/\/wykamol.com\/uploads\/files\/CM20_BBA.pdf\"\u003eCM20 BBA\u003c\/a\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca aria-label=\"Visit a webpage about Bba certification clever shield cm20 cavity drain membrane 18 5595\" title=\"Bba certification clever shield cm20 cavity drain membrane 18 5595\" href=\"https:\/\/wykamol.com\/uploads\/files\/BBA-Certification-Wykamol-CM20-Cavity-Drain-Membrane-18-5595.pdf\"\u003eBBA Certification Clever Shield CM20 Cavity Drain Membrane 18 5595\u003c\/a\u003e\u003c\/p\u003e\n\u003ch5\u003ePerformance\u003c\/h5\u003e\n\u003cp\u003e\u003ca aria-label=\"Visit a webpage about Declaration of performance cm20 cavity drain membrane wpdop05 2019 08\" title=\"Declaration of performance cm20 cavity drain membrane wpdop05 2019 08\" href=\"https:\/\/wykamol.com\/uploads\/files\/Declaration-of-Performance-CM20-Cavity-Drain-Membrane-WPDOP05-2019-08.pdf\"\u003eDeclaration Of Performance CM20 Cavity Drain Membrane WPDOP05 2019 08\u003c\/a\u003e\u003c\/p\u003e\n\u003ch5\u003eTDS\u003c\/h5\u003e\n\u003cp\u003e\u003ca aria-label=\"Visit a webpage about Cm20 cdm data sheet\" title=\"Cm20 cdm data sheet\" href=\"https:\/\/wykamol.com\/uploads\/files\/CM20-CDM-DataSheet.pdf\"\u003eCM20 CDM Data Sheet\u003c\/a\u003e\u003cbr\u003e\u003c\/p\u003e","brand":"Clever Shield","offers":[{"title":"CM20 2m X 20m YELLOW (Hi Vis)","offer_id":57035878924663,"sku":null,"price":183.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0321\/5320\/6920\/files\/wykamol-cm20-cavity-drain-membrane-waterproofing-system-550.webp?v=1765879373","url":"https:\/\/clevershieldcoatings.co.uk\/products\/cm20-cavity-drain-membrane-for-basements-2m-x-20m-yellow-hi-vis","provider":"Clever Shield - Asset Protection","version":"1.0","type":"link"}