The Pros and Cons of Having HVAC Units on Flat Roofs


Flat roofing provides additional space to those buildings with little interior storage and space. The flat surfacing is especially great for heavier equipment when ground space is limited. It is also a more convenient location for your HVAC unit, which is one of the most commonly placed items on flat roof structures.

There are Pros and Cons to having the HVAC Unit on your Roof


One of the most important benefits to having an HVAC unit on the roof is that the unit is no longer an obstruction for your customers or clients. It also keeps any loud sounds the unit makes away from the public. During the winter months, these units can turn on and off frequently, but when the noise is on the roof, it is not a disturbance to people.

When HVAC units are on the ground floor, maintenance and upkeep is also performed on the ground and this can cause major obstructions and disturbances. With the unit on the roof, maintenance crews can work on the unit without getting in anyone’s way.

HVAC units create a large amount of condensation, which will need to be frequently drained. When it is on the ground next to your building, any leaks can cause potential accidents and a big mess. When up on the roof, condensation flows into the gutters and away from the roof in a much more orderly fashion.


The weight of the HVAC unit can potentially cause damage to your roofing membrane. During routine maintenance and installation, the membrane becomes damaged which can cause leaks that may get into the building.
Always ensure installation on the roof is done properly to avoid low spots on the roof surface which can lead to pooling, especially after rain. If there is pooling around the unit that is allowed to sit for days the interior material of your roof can begin to deteriorate. Always fill in low spots to avoid this potential damage.

When the unit is on the roof and out of sight, it can be easy to forget about its upkeep and maintenance. The condensation line from the unit can cause malfunctions if not checked regularly and pooling water can cause mold and rot as well as leaks.

When you know the pros and cons of having your HVAC unit on the roof, you can make the best decision for your building. While it is more practical to have these units on the roof, it is essential that you remember they are there and schedule regular maintenance. So long as they are regularly maintained, your rooftop HVAC unit and your roof will be just fine for a long time. Reach out to us today for any HVAC installation and flat roofing questions.

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