Add-Ons
Enhancements for Curbs and Curb Adapters
Curbco offers a range of standalone enhancements designed to boost system performance and extend equipment life.
VIB-ISO Rail System (VIR)
The VIB-ISO Rail (VIR) system is engineered to sit between the rooftop unit and existing curb, reducing vibration transfer to the building structure. It’s a smart, dual-purpose solution—minimizing operational vibration while also providing seismic and wind restraint to keep the unit securely anchored.
Each VIR system is custom-engineered to match the specific rooftop unit and meet all customer requirements. Available in 1” or 2” deflection options, the VIR is factory-assembled with springs and restraints pre-installed to save time and labor on-site. Installation is straightforward, requiring only basic tools and minimal effort to secure it to the curb.
Reliable. Quiet. Easy to install. That’s the VIR advantage.
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Call Us 281.469.8855Why Use Vibration Isolation?
Rooftop units generate mechanical vibration from internal components like fans and compressors. While some parts can be isolated, most cannot—making full-unit vibration isolation the most effective solution.
Curbco’s VIR System uses coil springs to absorb vibration at the source, protecting the building structure and extending equipment life. Designed with advanced FEA technology, each system includes factory-installed seismic and wind restraints for code compliance and easy installation.
Reliable performance. Less noise. Less wear.
Vibration Isolation Rail (VIR) System Requirements
Aluminum isolation rails must provide continuous support and vibration control between the rooftop unit and the curb.
Seismic and wind restraints must be fully integrated into the upper and lower rails and assembled by the manufacturer to ensure quality and compliance.
Upper and lower rails shall be constructed from high-strength aluminum for durability and corrosion resistance.
Springs must be factory-installed to ensure proper alignment and consistent performance.
The rail system must be sealed from environmental exposure using a flexible membrane.
All mechanical connections to the unit must include flex connectors to prevent vibration transfer to the building structure.
All curb-mounted rooftop equipment should be supported by a VIR system for optimal isolation and protection.
Hurricane Clips
Hurricane Clips provide added protection against extreme wind events by securing the rooftop unit (RTU) to the curb. In severe weather, they help prevent the unit from shifting or detaching—reducing the risk of costly damage, system failure, or injury.
By keeping the RTU anchored in place, hurricane clips protect not just the equipment, but also the people and operations inside the building.
A small addition that delivers powerful peace of mind.
Gasket Material
Gaskets create a watertight seal between the curb adapter and the existing curb below, as well as between the adapter and the rooftop unit above. This seal helps prevent leaks, protect internal components, and ensure long-term system performance.
Extra gasket material is available for custom installations or to replace worn seals in the field—because even the smallest details make a big difference.
