Altra Custom Manufacturing Inc., 620 Supertest Rd Unit 6, North York, ON M3J 2M9
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Roof Curbs
Roof Curbs
Altra Custom Manufacturing Inc. roof curbs are engineered to deliver a secure, weather-tight connection between a building’s interior systems and its external rooftop installations. Designed for versatility, these curbs provide reliable support for a wide range of applications including fans, ventilators, ductwork, piping, and plumbing penetrations. They are also suitable for integrating skylights and roof hatches, making them an essential component in modern roofing systems.
Manufactured using heavy-gauge galvanized steel or aluminum, these curbs are built for long-term durability and structural strength. Each unit features continuously welded and precisely mitered corners, ensuring maximum resistance against water intrusion and environmental stress. For larger installations, internal reinforcements enhance load-bearing capacity, while the integral base flange simplifies installation and improves stability.
Additional features such as pressure-treated wood nailers and fiberglass insulation improve thermal efficiency and ease of flashing. With multiple configurations available, Altra Custom Manufacturing Inc. roof curbs provide a dependable and adaptable solution for diverse roofing applications.
Pate roof curbs create a water-tight transition between the interior and exterior of the building. Roof curbs will accommodate fans, ventilators, piping, duct work and plumbing penetrations. Curbs will also accommodate skylights and roof hatches. See our in-stock roof curbs here.
- Heavy-gauge galvanized steel or aluminum construction, with integral base flange.
- Continuously welded and mitered corners.
- Larger sizes internally reinforced.
- Pressure-treated wood nailer with 1-1/2″ thick fiberglass insulation and simple flashing detail.
- Sound attenuating galvanized steel panels with fiberglass insulation absorb up to 40% of ventilator noise, with air flow interference of only 4%.
| Product Group | Description |
| PC-2 | Straight-sided curbs – most common – lightweight fill or tapered insulation |
| PC-1 | Canted-design – 45-degree bend at base – single ply or rubber/PVC roof |
| PC-5 | Raised-cant design – 45-degree bend and elevated base – insulated roof deck |
| PC-2SF | Straight-sided curbs – extended base flange – pitched roofs |
| PC-2SL | Straight-sided curbs – loose base flange – adjust in field for unknown pitched roof |
| PC-2P | Straight-sided curbs for standard RTUs |
| PC-4IL < | Heavy duty, straight-sided curb, exterior insulation and liner – large HVAC units |
| PC-2DHP | Straight-sided curbs with damper holding plate |
| PC-1DHP | Canted-design curbs with damper holding plate |
| PC-5DHP | Raised-cant curbs with damper holding plate |