In this article you can read everything about insulating vibration produced by an outdoor unit.

Outdoor Unit Vibration Insulation on a Flat Roof

Insulating the vibration caused by an outdoor unit

Place a concrete tile on the roof that offers enough space to put the outdoor unit of your air-conditioner or heat pump on top of it. Then, cut a mat of Regufoam D300 (art. nr. M0718) in 8 equal pieces. Place under each corner of every leg (or Bigfoot) of the unit one piece of Regufoam.

Now, the outdoor unit is elevated by about 1 inch, resting on vibration insulating pieces of Regufoam and underneath a concrete tile. Afterwards, check under the roof, or listen at the ceiling if the humming noise of the outdoor unit has sufficiently been insulated.

Place the remaining 4 pieces of Regufoam under the already placed pieces, if you still perceive some low tones. We don’t recommend to add even more vibration insulation material, since this could lead to instability, causing clearance of the pipework. Make sure that the unit still stands steady after applying more Regufoam.


Once the vibration of the outdoor unit has been sufficiently insulated, you should provide the edges of the Regufoam with Acustitape all around in order to prevent water from penetrating. After that, the pieces of Regufoam can be attached to each other and to the legs (or Bigfoots) using Sika Flex mounting kit.

What do I need for insulating the vibration of an outdoor unit?
In order to insulate your outdoor unit, you should order concrete tiles yourself. From our web shop you need the following:

  • 1x of Regufoam D300, article nr. M0718
  • 1x Acustitape, article nr. M0177
  • 1x Sika Flex Mounting kit, article nr. K0974


We don’t have solutions for outdoor units that are connected to the wall.

Fill in our contact form if you have any questions concerning this topic. If you are searching for a heat pump enclosure, then click here: DICE heat pump enclosure.