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Frequently Asked Questions

What is a roof curb? A roof curb is a raised frame installed on commercial roof surfaces for the purpose of elevating mechanical equipment, such as an HVAC roof top unit or RTU. This roof curb also supports and allows for roof penetration of the supply and return duct work from the installed roof top unit into the building. 

What is a roof curb adapter? Eventually all HVAC equipment fails, and requires replacement. Many RTU manufacturers design their units so that they will not match their competitors' unit footprint. Roof curb adapters make it possible for the installation of a new RTU that may not match the original roof curb exterior dimensions and supply and return duct locations and dimensions. 

Why should I purchase a roof curb adapter? Utilizing a roof curb adapter for your installation will save you time and money. Labor costs and materials are drastically reduced by not having to remove the original flashed in roof curb, and install duct transitions to match and seal to the new unit. No roofer or additional duct modification is required when using a typical roof curb adapter.

What type of HVAC equipment does your roof curb adapter fit? We manufacture custom curb adapters for all brands, sizes, tonnages, and for a variety of applications. 

How long does it take to install a roof curb or curb adapter? Installation time of a curb adapter is a matter of a few hours, meaning far less headache and increased profitability than the alternative!

What does the typical installation process look like? To install a curb adapter, first turn off power and/or gas supply and disconnect from the existing RTU. Ensure the existing return & supply ducts are not fastened to the unit, then lift the existing RTU off the curb with a crane, removing it from the roof. If there was a curb adapter already installed, remove it now to expose the original roof curb that is flashed into the building's roof. Prepare the surface of the original roof curb with the supplied gasket around the outside perimeter and around both supply and return ducts. Seat the new curb adapter on top of the original roof curb, ensuring a proper fitment and seal. Prepare the top of the curb adapter with gasket around the outside perimeter and around both supply and return duct openings. Lift unit with a crane over the curb adapter, aligning supply and return and lower into place until fully seated. Connect power and or gas as necessary.

Are there any disadvantages from using a roof curb adapter? No! We custom design each curb adapter for an exceptional end result. We account for all factors, including proper airflow, structural integrity, water runoff, and minimal height addition. 

How do I know what to order? Typically a curb adapter is ordered by the existing RTU's brand and model information, and the new RTU's brand and model. There are times when this information is not available. When this occurs, field measuring may be required. We must also be alerted to anything within close proximity to the existing unit, as this may impact the curb adapter. Learn more about Measuring for a curb adapter HERE. 

What is a fan curb? A fan curb is similar to a roof curb, but does not have return and supply duct supports. Fan curbs have only one opening in order to move air in one direction or the other. They are insulated with a 1.5" fiberglass rigid insulation, and constructed with a 2" X 2" nailer on top.

Do you offer a warranty on your roof curbs? Yes, we offer a warranty on all of our products and stand behind them with the best service in the industry.

Still have a question? Contact us directly and one of our representatives will be more than happy to help!

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