The best type of attic insulation depends on where you live, your budget, and what stage of construction the attic is in. For example, if you're building a house, then structural insulated panels are a worthy investment since they're easy to install during construction and they're the most energy-efficient type of insulation.  

Additionally, if you live in a very warm climate, then you can potentially save quite a bit of money by opting for reflective insulation, which is more affordable than comprehensive insulation but doesn't work well for cool climates. Blown-in, loose-fill, and spray foam insulation are all great options for attics in moderate climates.

Bubble wrap is better for moving since it can be cut to size, whereas dish foam comes in precut sheets that are harder to manipulate. However, if you’re packing items like dishes, wine glasses, picture frames, or mirrors, dish foam will protect them better. Ensure you measure your box beforehand so you know what size dish foam to purchase. 

The best type of insulation for your home depends on your specific needs, climate, and the area you are insulating. For new construction, structural insulated panels are a highly energy-efficient option that is easy to install during the building process. In very warm climates, reflective insulation can be a cost-effective choice. For cold climates, fiberglass is an excellent option due to its high R-value and resistance to settling over time. Spray foam works well in humid environments because of its moisture-resistant properties. For standard attics, loose-fill, spray foam, or blown-in insulation are all suitable options.

Radiant barriers and insulation serve different purposes, so one is not inherently better than the other. Radiant barriers reflect radiant heat, helping keep spaces cool, especially in hot climates, while insulation slows heat transfer through conduction. For optimal energy efficiency, it’s best to use both together. 

Radiant barriers can enhance the performance of insulation by preventing heat gain in the summer and heat loss in the winter. The choice between them depends on specific climate conditions and the building’s design requirements.