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3M™ Fire Barrier Duct Wrap 15A
Installation Techniques

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3M Fire Barrier Duct Wrap 15A system should be installed in accordance with the following installation instructions.

Material and Equipment

• 3M Fire Barrier Duct Wrap 15A blanket, 1-1/2 in. (38 mm) thick, 24 in. (60 cm) or 48 in. (121 cm) wide, 20 ft. (609 cm) standard length. The 48 in. (121 cm) wide blanket helps to minimize waste.
• Aluminum foil tape.
• Minimum 3/4 in. (19 mm) wide filament tape.
• Carbon steel or stainless steel banding material, minimum 1/2 in. (12,7 mm) wide, minimum 0.015 in. (0,38 mm) thick, with steel banding clips.
• Hand banding tensioner, crimping tool, and banding cutter.
• Minimum 12 gauge copper-coated steel insulation pins; galvanized steel or stainless speed clips, minimum 1-1/2 in. (38 mm) square or 1-1/2 in. (38 mm) dia. round, or equivalent sized insulated cup-head pins; capacitor discharge stud gun.
• Access door hardware: four galvanized steel thread rods, 1/4 in. (6 mm) diameter by 4-1/2 in. to 5 in. long (114 mm to 127 mm) with 1/4 in. (6 mm) wing nuts and 1/4 in. (6 mm) washers: 4 in. (102 mm) long steel hollow tubing to fit threaded rods.
• Minimum 4.0 lb. (1,8 kg) density mineral wool or scrap pieces of 3M Fire Barrier Duct Wrap 15A.
• 3M Fire Barrier 1000 N/S, 1003 S/L or 2000+ Silicone Sealant.

Storage: The 3M Fire Barrier Duct Wrap 15A and 3M Fire Barrier 1000 N/S, 1003 S/L and 2000+ Silicone Sealants must be stored in a dry warehouse environment. Pallets should not be stacked.

Preparatory Work: 3M Fire Barrier Duct Wrap 15A is installed with common tools, such as knives, banders and capacitor discharge guns for applying insulation pins. In order to install the duct firestop system, the surfaces of all the openings and penetrating items need to be clean, dry, frost free and free of dust.

Method: To minimize waste, 3M Fire Barrier Duct Wrap 15A material should be rolled out tautly before measuring. General instructions for installing the 3M Fire Barrier Duct Wrap 15A include a one-layer wrap construction applied directly to the duct. The 3M Fire Barrier Duct Wrap 15A blanket is wrapped around the perimeter of the duct and is cut to a length to overlap itself not less than 3 in. (76 mm). The overlap made by adjacent blankets forms the “longitudinal” overlap.
Aluminum foil tape is used to seal all cut edges of the blanket and any tears in the foil scrim.

There are three (3) approved installation techniques for installing the 3M Fire Barrier Duct Wrap 15A (See Figure 1):

1. Telescoping 3 in. (76 mm) Overlap Wrap
   With the telescoping overlap wrap method, each blanket overlaps one adjacent blanket, and each blanket has one edge exposed and one edge covered by the next blanket as shown in Figure 1. The visible edges of the perimeter overlaps all point in the same direction.
2. Checkerboard 3 in. (76 mm) Overlap Wrap
   With the 3 in. (76 mm) checkerboard overlap wrap method, blankets with both edges exposed alternate with blankets with covered edges, as shown in Figure 1. The visible edges of the perimeter overlaps alternate their directions and appear on every other blanket.
3. Butt Joint With Collar
   With the butt joint and collar method, adjacent blankets are butted tightly together and 6 in. (152 mm) wide collar of 3M Fire Barrier Duct Wrap is centered over the joint, overlapping each blanket by 3 in. (76 mm) minimum as shown in Figure 1.
   In all three overlap techniques the perimeter overlap can occur at any location on the duct.
   The blanket is mechanically attached to the duct by steel banding or by welded insulation pins and clips for all three installation methods listed above.

For Banding Only (See Figure 1)
Filament tape can be used to temporarily hold the blanket in place until the banding is applied. The steel banding is applied around the duct 1-1/2 in. (38 mm) from each edge of the blanket, and maximum 10-1/2 in. (26,7 cm) centers. The banding is placed around the material and tightened so as to sufficiently hold the 3M Fire Barrier Duct Wrap 15A in place against the duct, compressing the foil but not cutting the foil.

Additional Pinning to Prevent Sagging of the Wrap:
For Ducts 24 in. (60 cm) and larger in width, additional pins are needed to support the blanket on the bottom horizontal surface and on the outside face of a vertical duct run. Space pins a maximum of 10-1/2 in. (26,7 cm) apart in the direction of the blanket width, and a maximum of 12 in. (30 cm) apart in the direction of the blanket length. Refer to paragraph below for more information on Mechanical Fastening with Pins.

For Mechanical Fastening with Pins Only
Insulation pins are welded to the duct in the centers of the overlaps a minimum of 1-1/2 in. (38 mm) from each edge of the blanket, and spaced a maximum of 10-1/2 in. (26,7 cm) on center along perimeter overlap, and a maximum of 10-1/2 in. (26,7 mm) on center along longitudinal overlaps. The blanket is impaled over the pins and held in place by galvanized speed clips. Insulation pins that extend beyond the blanket wrap shall be turned down to eliminate sharp points. Insulated cup-head pins can be used at the same spacing requirements of the insulation pins.
NOTE: Support hangar systems do not need to be wrapped provided the hangar rods are at least a minimum of 3/8 in. (9,53 mm) diameter and spaced a maximum of 60 in. (152 cm) on center along the length of the duct. Use a minimum 2 in. x 2 in. x 1/4 in. (50 mm x 50 mm x 6,35 mm) steel angle steel support channel or SMACNA equivalent support system.

Access Door Installation (See Figure 2)
Four galvanized steel threaded rods, 1/4 in. diameter (6,35 mm) by 4-1/2 in. to 5 in. long (114 mm to 127 mm) are welded to the duct at the corners of the door opening. Four steel tubes, each 3 in. (76 mm) long, are placed over the rods to act as protection for the 3M Fire Barrier Duct Wrap 15A when fastening the door. Four insulation pins are welded to the door panel for installation of the blanket. One layer of 3M Fire Barrier Duct Wrap 15A is cut approximately the same size as the access panel and impaled over the insulation pins on the panel. It is essential that this layer fit tightly against the wrap surrounding the access door opening with no through openings. A second layer of 3M Fire Barrier Duct Wrap 15A is cut so as to overlap the first layer by a minimum of 1 in. (25,4 mm). The second layer is impaled over the pins and both layers are locked in place with galvanized speed clips. Pins that extend beyond the outer layer of 3M Fire Barrier Duct Wrap 15A shall be turned down to avoid sharp points on the door.

The insulated door panel is placed over the threaded rods and held in place with washers and wing nuts.
The details are shown in Figure 2.

Penetrations (See Figure 3)
When the duct penetrates a fire rated wall, ceiling or floor, an approved firestop system must be employed. Figure 3 illustrates a typical condition.
To firestop the wrapped duct, follow the installation parameters detailed in the following Omega Point Laboratories, Inc. systems:
FS 557 W, FS 558 F, FS 559 W, FS 560 F, FS 561 F, FS 562 W, FS 563 W, FS 578 F, FS 579 W

Figure 1
3M Fire Barrier Duct Wrap 15A Commercial Kitchen Grease Duct Systems
1 or 2 Hour Shaft Alternative Zero Clearance to Combustibles
Telescoping Wrap Technique With Banding For Ducts 24 inches (60,9 cm) or Less

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One Layer 3M Fire Barrier Duct Wrap 15A Steel Banding 1/2 in. (13 mm) Wide Min. 3 in. (76 mm) Min. Longitudinal Overlap 3 in. (76 mm) Min. Perimeter Overlap

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Figure 2 3M Fire Barrier Duct Wrap 15A Commercial Kitchen Grease Duct Systems 1 or 2 Hour Access Door System	Figure 3 3M Fire Barrier Duct Wrap 15A Commercial Kitchen Grease Duct Systems 1 or 2 Hour Through Penetration Systems 4-1/2 inch (11,4 cm) Concrete Floor or Wall
Access Hole 1/4 in. (6 mm) Dia. All Threaded Rods Access Cover – 16 Gauge Insulation Pins – Welded First Layer 3M Fire Barrier Duct Wrap 15A Cut Same Size As Cover Second Layer 3M Fire Barrier Duct Wrap 15A with 1 in. (25mm) Overlap On All Sides Speed Clips Aluminum Tape Covering All Exposed Edges Spool Pieces For Threaded Rods 1/4 in. (6mm) Diameter Wing Nuts	Floor/Ceiling or Wall Assembly Duct A. One Layer 3M Fire Barrier Duct Wrap 15A B Banding or Pinning C. Packing Material D. 3M Fire Barrier 1000 N/S, 1003 S/L or 2000+ Silicone Sealant For Wall Assembly Apply Sealant To Both Sides of Wall