Alta 201412 & M18 Sigrist Medium Pipe Chase Housing & Curb

The Alta AL-201412 Housing with ALTC-M18 18-inch Curb is a medium pipe chase system engineered for safe, weather-tight roof penetrations. Designed to support up to 16 lines with Sigrist Exit Seals, it provides exceptional versatility for mechanical and data applications. Constructed from heavy-duty aluminum with UV-protected powder coating and full thermal break insulation, this assembly ensures long-term durability, energy efficiency, and leak prevention. Its recessed lid, stainless hardware, and 3-inch skirt overlap deliver a secure, low-maintenance solution that performs in demanding environments.

Key Features:

• Accommodates up to 16 Sigrist Exit Seals
• .080″ aluminum housing and curb with UV protected powder coating
• Full thermal break insulation in housing and curb
• Recessed lid with gasket protection
• 20-year warranty on housing and curb

Housing Model AL-201412: 20.5″ length × 14.5″ width × 13.5″ height

Curb Model ALTC-M18: 18.5″ length × 12.5″ width × 18″ height

Material: .080″ aluminum body, lid, and curb

Exterior finish: UV protected powder coating, approx. 2 mil thickness

Interior: Full thermal break insulation in both housing and curb

Fasteners: Stainless steel throughout

Exit seals: Injection-molded ABS, supports ¼″ to 1 5/8″ OD pipe sizes, maximum 16 seals (8 per side)

Skirt/overlap: 3″ skirt overlap of housing over curb edge

Combined height: 28.5″ nominal (housing + curb − overlap)

• Select the AL-201412 Housing and ALTC-M18 Curb for your installation requirements
• Install the curb onto the roof deck, ensuring alignment and proper flashing with roofing membrane
• Place insulation pad into the interior of the curb to establish thermal break
• Set housing onto curb, align gasket, and verify 3″ overlap skirt sits correctly
• Insert Sigrist Exit Seals into openings, position around pipes, and secure
• Attach recessed lid, ensure lid gasket seats properly, and tighten stainless steel hardware evenly
• Seal all interfaces with roofing membrane and inspect for weather-tight fit

Q: What is the maximum number of Sigrist Exit Seals this assembly can hold?
A: Up to 16 total (8 on each side) for the AL-201412 housing.

Q: What pipe sizes do the Sigrist Exit Seals support?
A: They support OD pipe sizes from ¼″ through 1 5/8″.

Q: What is the combined height of the housing plus curb?
A: When using AL-201412 with ALTC-M18, the combined height is approximately 28.5″.

Q: Is the housing and curb insulated?
A: Yes, both feature full thermal break interiors with insulation pads.

Q: What warranty does this product include?
A: The housing and curb have a 20-year warranty