MasterFlash No. 8 Square‑Base 171–343 mm – Black The MasterFlash® No. 8 Square‑Base is a premium pipe-flashing solution ideal for industrial, commercial and residential roofing applications. Engineered by Aztec Washer, this robust product delivers exceptional weather sealing where pipes penetrate the roof. Key Specifications Specification Details Pipe range 171–343 mm (6¾″–13½″) Base size 431 × 431 mm (17″ × 17″) Top opening 140 mm (5½″), clearly-marked cut-to-fit Base material Soft aluminium—easily shaped around roof contours Sleeve material Black EPDM rubber—UV, ozone and tear-resistant Temperature range −55 °C (continuous) to 100 °C (continuous), 135 °C (intermittent) Roof‑pitch suitability Up to 45° standard; extreme-angle variants suit 35°–65° Warranty 20 years standard Variations & Options MasterFlash No. 8 is available in a wide palette to match diverse roofing needs: Sleeve colours/materials Black EPDM (standard) Grey EPDM Silicone Red (high‑temperature variant) Other EPDM colours upon request: brown, blue, green, white, terra cotta, light/dark variations (see full chart) High‑temperature option Silicone sleeve: withstands up to 260 °C intermittently, 225 °C continuous Related size variants No. 8 X (closed top): 0–381 mm pipe range, base 495 mm Other sizes include: No. 9, 9 X, Maxi, Maxi‑XL—covering 20 mm to 1 000 mm pipe openings Performance & Installation Crafted for seamless operation: Flexible aluminium base conforms to metal, tile or membrane roofs for easy fitting Marked cutting lines ensure precise sizing for different pipe diameters EPDM sleeve flexibility absorbs thermal movement, reducing stress on the seal Straightforward installation: slide over pipe, mould base by hand, seal with silicone sealant, secure with self-drilling screws or rivets Why Choose the MasterFlash No. 8? Long-term reliability backed by a 20-year manufacturer warranty Robust resistance to weather, UV, ozone, temperature extremes from −55 °C to 135 °C Versatile styling with multiple colours and high-temp silicone option—ideal for matching diverse roof finishes Adaptable sizing covers common 171–343 mm pipe penetrations, with related models for smaller or larger needs The MasterFlash No. 8 Square‑Base 171–343 mm (Black) is a top-tier EPDM flashing, meticulously designed for long-lasting, watertight pipe penetrations in virtually any roof type. With flexible materials, colour options, and easy installation, it blends aesthetic choice with lasting performance. A 20‑year guarantee seals the promise of peace of mind. What is the highest temperature a Master Flash® pipe flashing will handle? – All EPDM MasterFlash flashings 135°C intermittently. – A silicone red flashing has a high resistance of 260°C intermittently. What type of sealant should be used on the Master Flash® flashings? – A good quality roof & gutter silicone sealant should always be used when installing a Master Flash pipe flashing for metal roofs. What type of screws should be used to fasten the flashings? – The use of a self-drilling screw or pop rivet (sealed) is always recommended. What is the life expectancy of the Master Flash® flashings? – All Master Flash products carry a 25-year warranty. What is the maximum roof pitch that the flashings can be used for? – Most of our products are designed to cater to a roof pitch of 45°. If more is required, then our Master Flash Extreme Angle range is designed with a built in 40° pitch and therefore can handle a roof pitch from 35° – 65°. Is there a product that can flash a Square Pipe? – Yes, our Master Flash Square Vent Range is available and will suit penetrations from 20mm – 125mm. Now also available in a lead base option. Colour Black, Grey or Silicone Red Size Pipe Range: 171mm – 343mm Base Range: 432mm
