What types of insulations are considered permissible in exterior walls?

The correct choice encompasses a variety of insulation types that are widely accepted in the construction of exterior walls as per the guidelines of the International Residential Code. Fiberglass batts, foam boards, and spray foam each offer unique properties that enhance thermal performance and energy efficiency in buildings.

Fiberglass batts are a common choice due to their affordability and ease of installation. They provide excellent thermal resistance and are suitable for framing cavities in walls. Foam boards, recognized for their high insulating value relative to thickness, can be utilized in various applications including continuous insulation on exterior walls. Spray foam insulation is particularly effective for filling gaps and cracks, providing both thermal insulation and an air barrier, which is essential for maintaining indoor climate control.

Permitting a range of insulation materials allows builders flexibility in meeting energy efficiency requirements while also accommodating different project needs and local climate conditions. The diversity in insulation options reflects modern advancements in building practices and materials, promoting better energy conservation in residential construction.