Which method of insulating involves applying material in a format that fills gaps and cracks?

The method of insulating that involves applying material in a format that effectively fills gaps and cracks is spray foam insulation. This insulation type is designed to expand upon application, which allows it to adhere closely to surfaces and fill even the smallest openings. This characteristic makes it particularly useful for sealing air leaks, enhancing thermal performance, and preventing moisture intrusion.

Spray foam insulation also creates an airtight barrier, which is beneficial for energy efficiency. Additionally, because it can conform to irregular shapes and spaces, it offers a level of versatility that is advantageous in attics and other hard-to-reach areas. This makes it a favored choice among homeowners and professionals for achieving a comprehensive insulation solution that minimizes air infiltration and maximizes energy savings.