To minimize noise transmission from a furnace installed in the attic, installers should:

To minimize noise transmission from a furnace installed in the attic, suspending the furnace from the roof trusses is an effective strategy. This approach helps isolate the furnace from the structure of the building, reducing the transfer of vibrations and sound waves to the walls and ceilings below. When a furnace is rigidly mounted on the attic floor, vibrations produced during operation can easily travel through solid materials, resulting in greater noise levels in the living areas. By suspending the furnace, you create a buffer that can absorb and dampen sound, thus minimizing overall noise.

While options such as soundproof insulation, lower RPM motors, and reducing fan speed may contribute to a reduction in noise generation or transmission, suspending the furnace directly addresses the root cause of noise transmission—vibration and structure-borne sound. Properly implemented, this method is typically more effective than simply relying on insulation, motor speed adjustments, or fan modifications alone.