How Does The Cellulose Insulation Work

Insulation made from recycled paper

You sure know that (today´s) cellulose insulation is made from old, recycled paper and you may ask yourself how does it actually work.
Can paper be used as an insulation material?
That paper that sets on fire by a single spark or make soggy by a single drop of the water?

Cellulose insulation manufacturing

The old paper is first decomposed to the cellulose fibres, the finer the fibres are the better.
Fiber insulation quality, in general, depends on how the fibres can encapsulate the air (the main insulation medium in this case).

Actually, the material has better insulation properties if it has fine and long fibres which, after application, form firm material (no matter if we talk about blown in cellulose insulation or the cellulose fibre batts) with some air captured within.

The air should not move (moving the air means exchanging the warmth) from one part of the insulation to another.
This (no air exchange) applies also if the cellulose batts are used in the vented roof.

Fiberglass vs cellulose insulation comparison

In December 1989 and January 1990, the university of Colorado studied the insulation performance of cellulose versus fiberglass insulation, so called Colorado Study.

Those people built two buildings, one insulated with fiberglass (R-19 in the walls and R-30 in the ceiling), the second one was insulated with cellulose insulation with the same measured R-values. After 3 weeks test they found out that:
- the cellulose insulated house consumed 26.4% less energy than the fiberglass insulated house;
- in terms of insulation efficiency, the cellulose insulated building performed 38% better than fiberglass insulated building even though both houses had the same R-value.