Seal-Tite Industrial Gutter

Seal-Tite Industrial Gutter IG-B is the IG-B version of Metal-Era's Seal-Tite industrial gutter, a metal gutter fixed to a wood nailer at the edge of a low-slope roof. It is supplied in 12 ft. lengths with pre-punched holes, so no drilling is needed in the field. The hangers are heavy aluminum straps that hook under the leading edge of the gutter and rotate into place. Each hanger is free-floating, and the gutter is free to move with thermal expansion and contraction.

The gutter is furnished to the drainage capacity and size required, and it accepts either a roof flange or slotted drain bars for ballast retention. It also adapts to flow-through gravel stops. Metal-Era describes the heavy-gauge hangers as built to carry larger volumes of water along with extreme snow and icing conditions.

Metal-Era lists the Seal-Tite Industrial Gutter family as IG-1, IG-2, IG-3 and IG-B. This page covers IG-B. Gutters like this one form part of the roof-edge and gutter installation and drainage systems used on commercial buildings, where the gutter sits at the perimeter and receives water from the roof membrane.

IG-B is made in four sizes, identified by the C dimension in inches. Each size has its own product ID and a B dimension (inside width) and an A dimension:

• IGB-C6: C = 6 in., B = 4 1/8 in., A = 4 1/2 in.
• IGB-C7: C = 7 in., B = 6 in., A = 6 in.
• IGB-C8: C = 8 in., B = 7 in., A = 7 in.
• IGB-C9: C = 9 in., B = 8 in., A = 8 in.

The largest downspout that fits any IG-B size must not exceed the B dimension minus 9/16 in.

IG-B has a single B dimension. The IG-1 and IG-2 versions are drawn with two, B1 and B2, and the largest downspout on those is limited by B2 minus 9/16 in. A gutter flange of a specified length and a specified flange angle can be added as options. Quantities are ordered in lineal feet of 12 ft. lengths.

IG-B is formed from one of four materials:

• 24-gauge galvanized steel
• .040-in. aluminum
• .050-in. aluminum
• .063-in. aluminum

Standard colors are coil-coated, and a 30-year Kynar 500 finish warranty is included on them. Custom post-coated Kynar 500 colors carry an included 10-year Kynar 500 finish warranty, and a 20-year warranty is available on request. Anodized finishes are also offered with a 5-year warranty. Coil-anodized finishing has no warranty. Post-coat, Class 1 batch anodizing carries 5 years, with an option to raise it to 10 years at an upcharge.

The hangers are supplied with the gutter and are punched with pre-slotted holes. They are set at 30 in. on center and are fastened through the back of the gutter into the wood nailer with the provided #10 x 2 in. stainless steel fasteners.

The gutter itself has 5/32 in. x 1/2 in. slotted holes at 12 in. on center. The slots allow thermal movement of the metal and set the fastener spacing. The gutter is nailed to the nailer with the provided 1 1/4 in. galvanized roofing nails.

• Lap joints: 2 in. laps are provided between 12 ft. sections.
• Rivets: 1/8 in. stainless steel pop rivets are provided.
• Sealant and tape: non-curing sealant goes inside each miter end, at outlets and at end caps, and a 6 in. wide EPDM or butyl pressure-sensitive tape is recommended over each lap joint.

The installation instructions for IG-1, IG-2 and IG-B number the steps as follows.

1. Membrane installation: the primary roof material manufacturer's recommendations and the architect's details are followed for installing the roof membrane alongside the gutter system.
2. Miter installation: non-curing sealant is applied to the inside of each miter end.
3. Gutter installation: sections are installed from right to left as seen from the roof. The notched end of a section is inserted 2 in. into the open end of the next section, which carries the applied sealant. The lap is riveted at 2 in. on center with the provided 1/8 in. stainless steel pop rivets. Miter ends and expansion joints are field notched as required. Sections are nailed to the nailer at 12 in. on center with the provided 1 1/4 in. galvanized roofing nails.
4. Hanger installation: each hanger is hooked under the leading edge of the gutter and rotated into place, then fastened at 30 in. on center.
5. Expansion joint installation, where necessary: joints go at the locations on the roof plans or at a maximum of 48 ft., and are nailed into place as in step 3.
6. Outlet installation: the outlet location is set and a hole is field cut. The aluminum outlet is inserted, riveted with the provided pop rivets at 2 in. on center on each flange, and sealed with non-curing sealant.
7. End cap installation: end caps go on at all terminations, are field riveted at 2 in. on center and are sealed with non-curing sealant.

Miters are factory fabricated, which removes field fabrication. Unless noted otherwise they are made with a non-penetrating quicklock joint and then factory sealed watertight. For Seal-Tite Industrial Gutter, welded accessories need a minimum material thickness of .050 in. Outside and inside 90-degree miters are ordered as welded or quicklock, and right-hand and left-hand end caps are specified separately. Non-90 miters, quicklock radius and welded radius gutters have their own print approvals, and custom radius and specially fabricated pieces are available.

Two expansion joint styles are offered: Style 1, a SMACNA design, and Style 2, a free-flow design. The Style 2 joint is built around a neoprene center section, 0.15 in. thick, factory bonded to .048 in. aluminum. A 12 ft. gutter length is cut into two 6 ft. pieces, and the joint fits between them. Heavy beads of non-curing sealant go inside each gutter section, which slides over the expansion plate until its lead edge meets the neoprene insert. The 12 in. long cover plate is centered over the joint once both sections are in place. It may be pop riveted to the expansion plate and gutter on one side only, to permit expansion.

Other Metal-Era pieces with print approvals for IG-B include:

• an external gutter bracket;
• Flow-Thru, ADB, ADL and ADW drain bars;
• thru-wall scuppers, including a TPO-coated version;
• collector boxes in pop-riveted and welded versions;
• the 5.2 in., 4 in. flange Eliminailer-T, for masonry and for metal deck.

IG-B shares its installation instructions with IG-1 and IG-2, and the same 20-year wind warranty applies across IG-B, IG-1, IG-2 and IG-3. The drawings differ in how the gutter section is dimensioned: IG-1 and IG-2 use B1 and B2 dimensions, while IG-B uses one B dimension. IG-3 has its own installation instructions and uses 6 in. wide splice plates in place of the 2 in. lap joints.

For IG-1, IG-2 and IG-3, the 5.2 in., 4 in. flange Eliminailer-T is drawn for masonry walls and for metal deck, with C8 and C9 sizes. It is an extruded aluminum T-bar protected by U.S. Patent 9,878,023 B1, used with a .090 in. x 1 in. termination bar and rigid polyiso roof insulation. On masonry, a minimum 6 in. isolation layer is required between the T-bar and the substrate, such as rubber or plastic strips, peel-and-stick membrane or Metal-Era isolation tape. IG-B has matching Eliminailer-T print approvals for masonry and for metal deck.

A 20-year, 120 mph Seal-Tite Gutter System wind warranty is available on orders that call for it. It runs for twenty years from the date of final acceptance. Metal-Era LLC will replace or repair the portion of the gutter system that has failed due to a defect in Metal-Era supplied materials, and its obligation over the life of the warranty is limited to the owner's original cost of the system.

• Covered products are the Seal-Tite Gutter Systems IG-B, IG-1, IG-2 and IG-3 only.
• All accessories must be manufactured by Metal-Era.
• The owner gives Metal-Era written notice within thirty days of discovering a failure.
• The warranty does not apply to damage from wind over 120 miles per hour, flying debris or natural disasters, to separation of the wood nailer from the building, to negligence, misuse or abuse, to non-Metal-Era metal work in the system, or to installation not in strict accordance with Metal-Era's specifications and printed instructions.

The finish warranties described under materials are separate.