Using which option would cause the greatest increase in the insulation value when re-siding with aluminum?

Choosing perforated reflector foil as the method to increase insulation value when re-siding with aluminum is highly effective due to its ability to reflect radiant heat away from the building. The perforated design allows for airflow while still providing substantial thermal resistance. This not only enhances the insulation value but also helps in reducing energy costs year-round by limiting heat transfer to and from the exterior.

In contrast, standard fiberglass insulation, while it provides decent thermal resistance, does not take full advantage of reflective properties that prevent radiant heat gain, especially significant in aluminum siding applications that can absorb and radiate heat. Reflective foil barriers are good but typically require a specific air gap to work effectively, and in some settings, may not be as efficient as perforated foil. Cellulose insulation can provide a good R-value and is environmentally friendly, but its performance as a radiant barrier does not compare to the dual function - insulation and reflectivity - offered by perforated reflector foil. Thus, it is the superior choice for achieving maximum insulation value in this context.