Our Products

Advanced Design
And Engineering



Curb Adapters

Rooftop Curbs

Fan Curb Adapters

Fan Curbs

Roof Equipment Rails


Fan Curb

(NOTE: If you are a contractor, please contact your local air conditioning distributor)

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  • (NOTE: Difference between O.D. & I.D. is 3 1/2")
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Fan curbs are used as roof support structures for fans and ventilators. Like our HVAC Curbs, they are available for flat, pitched, and metal or ridged roofs with or without insulation. Fan curbs can be either canted or self flashing.

The following variants and special purpose fan curbs are available:

  • Pitched Fan Curbs
  • Fan Curb Extensions
  • Pitch Corrector
  • Directional Fan Curbs
  • Fan Curbs for Metal Buildings
  • Self-Flashing Fan Curbs
  • Vibration Isolation
  • Job Specific (Custom Fan Curbs)

Roof Equipment Rails

Any piece of HVAC equipment is only as good as its installation which means that your roof equipment supports should boast the same quality construction and materials as the expensive units they hold in place. We start with 18-gauge galvanized steel, solid internal bracing, and continuous welded seams. These things are tough, we recently did a bench test and a 14” high support 36” long was able to hold over 7,000lbs!

Standard Features

  • 18 gauge galvanized body
  • Continuous welded seam
  • Wood Nailer
  • 24 gauge galvanized cap
  • Internal braces 24″ on center

Optional Features

  • 14-16 gauge galvanized body
  • .063 or .080 aluminum body
  • 18 gauge 304 stainless steel body
  • 18 gauge 304 stainless steel cap
  • Welded 18 gauge galvanized cap

Please download and complete the form linked below to get your roof equipment rails quote.

Add Ons

Curbco offers various standalone enhancements to improve system performance and extend lifespan. Including Vib-Iso Rail System, Hurricane Clips, and Gasket Material

Vib-Iso Rail System

The VIB-ISO RAIL (VIR) system is designed to sit between an existing roof curb and a curb mounted piece of equipment. The VIR is designed to reduce the vibration from a curb mounted piece of equipment to the building structure. Along with reducing the vibration from the roof-top-unit, the VIR also acts as a seismic and wind restraint to keep the unit attached to the roof curb. Each VIR system will be engineered to match the roof-top-unit and meet any customer requirements. The VIR system is available in either 1” or 2” deflection, depending on the customer’s requirements. The VIR system is shipped nearly fully assembled with the springs and restraints installed at the factory to reduce onsite labor. On site, the VIR design allows for quick assembly requiring only basic tools to install it to the existing roof curb.

Why use vibration isolation under your roof-top-units? Prepackaged roof-top-units have a number of different components that can create mechanical vibration. Some of these can be individually isolated but most cannot. The simplest and most economical way to solve this issue is to place the entire unit on a vibration isolation rail. The VIR system uses coil spring as a resilient media to absorb the vast majority of the vibration energy emanating from the unit. The VIR system was designed using the latest in finite element analysis technology, more commonly known as FEA. The VIR seismic and wind restraints are integrated into the design allowing the rails to be shipped assembled with the restraints installed, thus ensuring proper installation of the restraints.
1. Aluminum vibration isolation rails must give continuous support and isolation between the roof curb and the unit. 2. Seismic and wind restraints shall be integrated within the upper and lower rail and assembled by the rail manufacturer to ensure quality. 3. The upper and lower rails should be made of high strength aluminum to ensure strength and corrosion resistance. 4. The springs must installed by the manufacturer to ensure proper placement and quality. 5. The upper and lower rails need to be sealed from the environment using a flexible membrane. 6. All connections to the unit need to have flex connectors to ensure proper isolation from the building structure. 7. Curb mounted roof top equipment should be isolated by a VIR system.

Hurricane Clips

Hurricane Clips serve as an extra measure of protection against hurricane force winds. These clips secure the RTU to the curb to avoid costly damage and repair were the unit to shift during a weather event. Hurricane clips also serve to protect the people and equipment inside a building should winds be sufficient to move the unit off of the curb, where it could fall through the roof structure.

Gasket Material

Gaskets serve to provide a water-tight seal at the bottom of the curb adapter, where it connects to the existing curb, and at the top, where the HVAC unit rests. Extra gasket material for custom jobs or to replace weathered material is available.