{"product_id":"classicbond-epdm-external-corner-patch","title":"ClassicBond EPDM External Corner Patch","description":"\u003ch3\u003eUncured EPDM Patch for External Corners \u0026amp; Upstands\u003c\/h3\u003e\n\n\u003cp\u003eThe ClassicBond External Corner Patch is a pressure-sensitive, uncured EPDM flashing patch used to waterproof external corners, upstands and complex details on EPDM rubber roofing systems.\u003c\/p\u003e\n\n\u003cp\u003eMade from the same uncured Elastoform EPDM flashing used in \u003ca href=\"\/products\/classicbond-9-elastoform-epdm-flashing-tape\"\u003e\u003cstrong\u003eClassicBond 9″ tape\u003c\/strong\u003e\u003c\/a\u003e, the patch is highly flexible and self-curing, allowing it to stretch and mould tightly around corner profiles where standard cured EPDM membrane cannot be dressed reliably, without cutting or folding.\u003c\/p\u003e\n\n\u003cdetails style=\"margin-bottom:12px; border:1px solid #333; border-radius:10px; background:#1a1a1a; overflow:hidden;\"\u003e\n  \u003csummary style=\"cursor:pointer; font-weight:700; padding:16px 48px 16px 16px; font-size:18px; position:relative; list-style:none;\"\u003e\n    What This External Corner Patch Actually Is\n    \u003cspan style=\"position:absolute; right:16px; top:50%; transform:translateY(-50%);\"\u003e▸\u003c\/span\u003e\n  \u003c\/summary\u003e\n  \u003cdiv style=\"padding:16px; border-top:1px solid #333;\"\u003e\n    \u003cp\u003eThis patch is a pre-cut section of 9\" ClassicBond PS uncured Elastoform flashing tape.\u003c\/p\u003e\n    \u003cp\u003eIn practical terms:\u003c\/p\u003e\n    \u003cul\u003e\n      \u003cli\u003eManufactured from uncured EPDM membrane\u003c\/li\u003e\n      \u003cli\u003eLaminated to a pressure-sensitive adhesive backing\u003c\/li\u003e\n      \u003cli\u003eSupplied as a 300mm × 225mm (12″ × 9″) patch\u003c\/li\u003e\n      \u003cli\u003eEquivalent to a short length cut from a roll of 9″ uncured flashing tape\u003c\/li\u003e\n    \u003c\/ul\u003e\n    \u003cp\u003eIt’s designed as a convenient pre-cut solution when you only need to form one or two external corners, without purchasing a full roll of tape.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails style=\"margin-bottom:12px; border:1px solid #333; border-radius:10px; background:#1a1a1a; overflow:hidden;\"\u003e\n  \u003csummary style=\"cursor:pointer; font-weight:700; padding:16px 48px 16px 16px; font-size:18px; position:relative; list-style:none;\"\u003e\n    When to Use an External Corner Patch\n    \u003cspan style=\"position:absolute; right:16px; top:50%; transform:translateY(-50%);\"\u003e▸\u003c\/span\u003e\n  \u003c\/summary\u003e\n  \u003cdiv style=\"padding:16px; border-top:1px solid #333;\"\u003e\n    \u003cp\u003eThis uncured EPDM corner patch is ideal for:\u003c\/p\u003e\n    \u003cul\u003e\n      \u003cli\u003eExternal corners on EPDM roofs\u003c\/li\u003e\n      \u003cli\u003eUpstands up to approx. 150mm\u003c\/li\u003e\n      \u003cli\u003eCorners at:\u003c\/li\u003e\n    \u003c\/ul\u003e\n    \u003col\u003e\n      \u003cli\u003eRoof perimeters\u003c\/li\u003e\n      \u003cli\u003eParapet walls\u003c\/li\u003e\n      \u003cli\u003eSkylights\u003c\/li\u003e\n      \u003cli\u003eBox gutters\u003c\/li\u003e\n    \u003c\/ol\u003e\n    \u003cul\u003e\n      \u003cli\u003eDetailing work where the membrane needs to stretch over a corner without cutting\u003c\/li\u003e\n    \u003c\/ul\u003e\n    \u003cp\u003eBecause this EPDM is uncured, it can be shaped smoothly around the corner without creating stress points. The EPDM tape begins to cure when it comes into contact with the \u003ca href=\"\/products\/classicbond-epdm-rubber-roofing-primer\"\u003e\u003cstrong\u003eClassicBond EPDM primer\u003c\/strong\u003e\u003c\/a\u003e.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails style=\"margin-bottom:12px; border:1px solid #333; border-radius:10px; background:#1a1a1a; overflow:hidden;\"\u003e\n  \u003csummary style=\"cursor:pointer; font-weight:700; padding:16px 48px 16px 16px; font-size:18px; position:relative; list-style:none;\"\u003e\n    When 9″ Uncured EPDM Tape Is the Better Option\n    \u003cspan style=\"position:absolute; right:16px; top:50%; transform:translateY(-50%);\"\u003e▸\u003c\/span\u003e\n  \u003c\/summary\u003e\n  \u003cdiv style=\"padding:16px; border-top:1px solid #333;\"\u003e\n    \u003cp\u003eIf you have:\u003c\/p\u003e\n    \u003cul\u003e\n      \u003cli\u003e\u003cstrong\u003eHigher upstands\u003c\/strong\u003e\u003c\/li\u003e\n      \u003cli\u003e\u003cstrong\u003eMultiple corners\u003c\/strong\u003e\u003c\/li\u003e\n      \u003cli\u003e\u003cstrong\u003eLonger or irregular detailing\u003c\/strong\u003e\u003c\/li\u003e\n    \u003c\/ul\u003e\n    \u003cp\u003eIt’s usually more practical to use ClassicBond 9″ PS uncured Elastoform flashing tape, which can be cut to any length required.\u003c\/p\u003e\n    \u003cp\u003e👉 Think of this patch as a ready-cut convenience option, while uncured tape is the better choice for larger or repeated details.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails style=\"margin-bottom:12px; border:1px solid #333; border-radius:10px; background:#1a1a1a; overflow:hidden;\"\u003e\n  \u003csummary style=\"cursor:pointer; font-weight:700; padding:16px 48px 16px 16px; font-size:18px; position:relative; list-style:none;\"\u003e\n    How the External Corner Patch Is Installed (Best Practice)\n    \u003cspan style=\"position:absolute; right:16px; top:50%; transform:translateY(-50%);\"\u003e▸\u003c\/span\u003e\n  \u003c\/summary\u003e\n  \u003cdiv style=\"padding:16px; border-top:1px solid #333;\"\u003e\n    \u003col\u003e\n      \u003cli\u003eClean the membrane surface thoroughly\u003c\/li\u003e\n      \u003cli\u003eIf the membrane is weathered, clean with \u003ca href=\"\/products\/classicbond-epdm-weathered-membrane-cleaner\"\u003e\u003cstrong\u003eWeathered Membrane Cleaner\u003c\/strong\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n      \u003cli\u003eApply \u003ca href=\"\/products\/classicbond-epdm-rubber-roofing-primer\"\u003e\u003cstrong\u003eClassicBond EPDM Primer\u003c\/strong\u003e\u003c\/a\u003e to the membrane and upstand\u003c\/li\u003e\n      \u003cli\u003eAllow primer to become touch dry\u003c\/li\u003e\n      \u003cli\u003eRound off all corners of the patch using scissors\u003c\/li\u003e\n      \u003cli\u003ePosition the patch and press it firmly into place, stretching it over the corner\u003c\/li\u003e\n      \u003cli\u003eRoll immediately with a seam roller and penny roller, working across the edges (not parallel)\u003c\/li\u003e\n    \u003c\/ol\u003e\n    \u003cp\u003e⚠️ \u003cstrong\u003eClassicBond EPDM Primer is required and is not included with this patch.\u003c\/strong\u003e\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails style=\"margin-bottom:12px; border:1px solid #333; border-radius:10px; background:#1a1a1a; overflow:hidden;\"\u003e\n  \u003csummary style=\"cursor:pointer; font-weight:700; padding:16px 48px 16px 16px; font-size:18px; position:relative; list-style:none;\"\u003e\n    Why Uncured EPDM Flashing Is Used for Corners\n    \u003cspan style=\"position:absolute; right:16px; top:50%; transform:translateY(-50%);\"\u003e▸\u003c\/span\u003e\n  \u003c\/summary\u003e\n  \u003cdiv style=\"padding:16px; border-top:1px solid #333;\"\u003e\n    \u003cp\u003eUncured EPDM flashing:\u003c\/p\u003e\n    \u003cul\u003e\n      \u003cli\u003eHas high elongation (can stretch over 400%)\u003c\/li\u003e\n      \u003cli\u003eIs self-curing once installed\u003c\/li\u003e\n      \u003cli\u003eAdapts easily to irregular shapes and profiles\u003c\/li\u003e\n    \u003c\/ul\u003e\n    \u003cp\u003eThis is why uncured flashing is specified for corners, penetrations at angle changes and complex details in EPDM roofing systems.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails style=\"margin-bottom:12px; border:1px solid #333; border-radius:10px; background:#1a1a1a; overflow:hidden;\"\u003e\n  \u003csummary style=\"cursor:pointer; font-weight:700; padding:16px 48px 16px 16px; font-size:18px; position:relative; list-style:none;\"\u003e\n    A Roofer’s Perspective\n    \u003cspan style=\"position:absolute; right:16px; top:50%; transform:translateY(-50%);\"\u003e▸\u003c\/span\u003e\n  \u003c\/summary\u003e\n  \u003cdiv style=\"padding:16px; border-top:1px solid #333;\"\u003e\n    \u003cp\u003eExternal corners are one of the most common failure points on EPDM roofs if the wrong material is used.\u003c\/p\u003e\n    \u003cp\u003eUsing uncured EPDM flashing, rather than cutting and sticking patches of EPDM like we have seen on many failed roofs - whether as a pre-cut patch like this or from a roll of 9″ tape - is the correct, compliant way to ensure a watertight finish. It stretches, beds in properly, and cures into the detail instead of fighting it. Once installed onto primed EPDM, the flashing tape forms a chemical bond with the EPDM rubber roof, forming a long-lasting corner detail.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/details\u003e","brand":"The Flat Roofing Shop","offers":[{"title":"Default Title","offer_id":56483531391307,"sku":"CB-Corner-Patch-Ext","price":7.7,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0997\/4054\/9451\/files\/external-corner-patch-for-epdm-rubber-roofing.webp?v=1773495389","url":"https:\/\/theflatroofingshop.co.uk\/products\/classicbond-epdm-external-corner-patch","provider":"The Flat Roofing Shop","version":"1.0","type":"link"}