Roof Curb Adapters are used to mount roof top mounted HVAC units (RTU’s) on existing roof curbs.  RTU’s are mounted on top of roof curbs and those roof curbs provide the following main functions:

  1. Attach the RTU to the building structure with considerations for wind and seismic loads.
  2. Direct the air flow from the supply outlet of the RTU into the supply ducting of the building and direct the return air from the building back into RTU.
  3. Seal the openings in the roof as an integral part of the roofing system.
  4. Some roof curbs also provide a function of vibration isolation to reduce noise generation and transmission into the building.  See our vibration isolation curbs.

The service life of the roofing system does not usually coincide with the service life of the RTU, so when an RTU needs to be replaced without replacing the roofing system, an adapter curb is used.  The functions of the Roof Curb Adapters are the same as the initial roof curb with the exception of being an integral part of the roofing system since the original curb continues to meet that function.  Plenums gives careful consideration to the airflow characteristics of our adapter curbs to prevent adding excessive pressure drop or noise generation.   We also offer wind load certifications for the most stringent wind engineering standards in the country since we are located in Florida.

Roof Curb Adapter Features

  • Heavy gauge galvanized steel construction.
  • Use existing duct.
  • Insulated with 1" - 1.5 PCF insulation.
  • 1/4" x 1-1/4" gasketing.
  • Most models shipped fully assembled.
  • Thousands of models designed and installed.
  • Welded construction.
  • Quick installation.
  • Custom options available.

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