Multi-Flash Master Flash

Multi-Flash Master Flash is a pipe flashing made by Aztec Washer Company for the metal roofing industry. It is two flashings in one: the same design is used as a standard flashing or as a retrofit flashing.

The retrofit use is for existing pipes and vents that need a wrap-around installation or are hard to reach, and a stainless-steel gripper is included to secure retrofit installations. The flashing is made of black EPDM rubber or high-temperature gray silicone and has a flexible aluminum base designed to mold to most panel configurations and roof pitches regardless of pipe location.

The flashing is made for metal roofs and comes in sizes from the #2 to the Maxi, with bases from 6 to 34 in. (152 to 863 mm). Across the sizes, the standard fit reaches pipes up to 28 1/2 in. (723 mm) and the retrofit fit covers pipes from 1 1/8 to 28 in. (28 to 711 mm).

Nine sizes are made: #2, #3, #4, #5, #6, #7, #8, #9 and the Maxi. The numbering starts at #1, the Multi-Port flashing with a 4 1/2-in. (114-mm) base, and counting it the range is ten sizes. Each size has two part numbers, one in black EPDM ending BA-G and one in gray silicone ending GX-G.

• #2: standard fit 7/8 to 4 in. (22 to 101 mm); retrofit fit 1 1/8 to 3 7/8 in. (28 to 98 mm); top opening 7/8 in. (22 mm); base 6 in. (152 mm); overall height 2 3/4 in. (70 mm); parts MF201BA-G and MF202GX-G.
• #3: closed top; standard fit closed to 5 3/4 in. (0 to 146 mm); retrofit fit 2 to 5 in. (50 to 127 mm); base 8 in. (203 mm); overall height 3 in. (76 mm); parts MF301BA-G and MF302GX-G.
• #4: standard fit 2 3/4 to 7 in. (69 to 177 mm); retrofit fit 3 to 6 1/2 in. (76 to 165 mm); top opening 2 3/4 in. (69 mm); base 10 in. (254 mm); overall height 4 3/4 in. (120 mm); parts MF401BA-G and MF402GX-G.
• #5: standard fit 4 to 8 1/4 in. (101 to 203 mm); retrofit fit 3 3/4 to 7 in. (95 to 177 mm); top opening 4 in. (101 mm); base 11 in. (279 mm); overall height 4 1/2 in. (114 mm); parts MF501BA-G and MF502GX-G.
• #6: standard fit 4 3/4 to 10 in. (121 to 254 mm); retrofit fit 4 1/2 to 8 1/2 in. (114 to 215 mm); top opening 4 3/4 in. (120 mm); base 12 in. (304 mm); overall height 4 1/2 in. (114 mm); parts MF601BA-G and MF602GX-G.
• #7: standard fit 6 to 11 in. (152 to 279 mm); retrofit fit 5 1/4 to 10 in. (133 to 254 mm); top opening 6 in. (152 mm); base 14 in. (355 mm); overall height 5 1/2 in. (140 mm); parts MF701BA-G and MF702GX-G.
• #8: standard fit 6 3/4 to 12 in. (171 to 304 mm); retrofit fit 6 1/2 to 12 3/4 in. (165 to 323 mm); top opening 6 3/4 in. (171 mm); base 17 in. (431 mm); overall height 5 3/4 in. (146 mm); parts MF801BA-G and MF802GX-G.
• #9: standard fit 9 1/2 to 20 1/2 in. (241 to 520 mm); retrofit fit 9 1/4 to 20 1/2 in. (234 to 520 mm); top opening 9 1/2 in. (241 mm); base 25 in. (635 mm); overall height 5 3/4 in. (146 mm); parts MF901BA-G and MF902GX-G.
• Maxi: standard fit 12 to 28 1/2 in. (304 to 723 mm); retrofit fit 11 to 28 in. (279 to 711 mm); top opening 12 in. (304 mm); base 34 in. (863 mm); overall height 7 1/2 in. (190 mm); parts MF951BA-G and MF952GX-G.

The sleeve is black EPDM rubber or high-temperature gray silicone, and both compounds are made for resistance to weathering from ozone and ultraviolet light. Flexibility in the sleeve absorbs vibration and pipe movement caused by expansion and contraction. The flashing uses compression seal technology.

Cut lines are marked on the flashing for the different pipe sizes, and the pipe diameters are visible on it for fitting. The stainless-steel gripper supplied with the flashing secures retrofit applications.

The black EPDM and the gray silicone of the Multi-Flash are tested to these values:

• Ozone resistance: 70 hours at 500 pphm for both compounds.
• High temperature, intermittent: EPDM +275°F (+135°C); silicone +500°F (+260°C).
• High temperature, continuous: EPDM +212°F (+100°C); silicone +437°F (+225°C).
• Low temperature: EPDM -67°F (-55°C); silicone -101°F (-74°C).
• Maximum compression set: EPDM 25%; silicone 50%.

For a standard installation, the pipe's outside diameter is found in the size table and the flashing is trimmed along the outline for that size. It is cut at least 20% smaller than the pipe's outside diameter. On steep roofs or deep corrugations, the next size up is used.

The standard sequence has five steps: measure and trim, slide, form, seal and complete. Base fastening uses Master Seal bonded washers and fasteners 1 to 1 1/2 in. apart around the whole base. The materials are the gripper, fasteners, washers, snips or scissors, a measuring tape, a marker or pencil and sealant.

A retrofit installation wraps the flashing around a pipe that is already in place. The flashing is cut at least 5% smaller than the pipe's outside diameter, and the next size up is used on steep roofs or deep corrugations.

The retrofit installation is shown in five steps. Three are measure and trim, wraparound and form, and complete. The other two cover the gripper, which is cut to fit with sealant applied, then slid on and crimped with pliers. The base is fastened in the same way as in a standard installation, with Master Seal bonded washers and fasteners 1 to 1 1/2 in. apart.

The warranty is 25 years for the EPDM rubber versions and 35 years for the silicone versions.

Related flashings in the Master Flash range include Master-Flex, Fire-Blox, the Roof Vent Sealing Adapter Multi-Flash, Extreme Angle, Square Vent and the 35 Year Master Flash.