Air and Sound Control
The seamless seal provided by cellulose insulation is an unbeatable blocker of air and sound infiltration, which is a huge comfort factor to consider when looking at insulation options.
Field tests have proven that a cellulose seal is 36% tighter than that of a fiberglass seal, which means the outside elements - be it weather or noise - have a tough time flowing into and throughout the building.
In 2005, The Conservation Services Group in Massachusetts conducted a study on air tightness in single and multi-family homes that had Energy Star approval ratings. There was two test groups, one for wall insulation and one for ceiling/roof insulation. The results showed homes using cellulose were significantly tighter than those using fiberglass.
There are more important factors than the selection of insulation material when you are concerned about sound control. (read the links to the right). That being said, designing a sound resistance wall means you want to block out sound paths or gaps in insulation, doors, windows, etc. Cellulose insulation, if applied to interior walls, can act as a great retarder of sound flow, keeping out or diminishing unwanted noises from room to room or from outside to inside the structure.