Not all of us are as warm blooded as the rest. As your body temperature rises with the warm weather you may find it necessary to kick on the air conditioner while your cool-blooded neighbors are still content with the windows open. So what do you do when your air conditioner fan turns on and makes noises that disturb the neighbors?
In most cases you will find that you cannot build a box around the air conditioning unit. The reason for this is because the air conditioner needs air in order to function properly. What you can do, however, is build a fence or wall around the sides of your air conditioner and include absorbing materials on the inside that will form a sound barrier. The fence or wall will really only need to go around three sides of the air conditioner and will only need to be about 6 inches taller than the air conditioner itself to be effective.
Use latticework for the exterior, apply mass loaded vinyl or some other soundproofing material to the inside, and plant some flowers or plants on the outside. You’ll not only cut down on noise but have an eye appealing addition to your landscape!