What type of insulation is typically recommended for basement wall applications?

Foam board insulation is typically recommended for basement wall applications due to its effectiveness in providing a continuous thermal barrier and moisture resistance. This type of insulation can be installed directly against the foundation wall, which helps minimize thermal bridging and air infiltration.

Basement walls are often prone to moisture issues, and foam board insulation offers a lower permeability compared to other insulation materials, which helps protect against mold and moisture accumulation. Additionally, foam board insulation has a high R-value per inch, providing better energy efficiency and comfort in the basement space.

While fiberglass batts and batt insulation can be used in certain contexts, they are less suitable for direct applications against basement walls due to potential moisture issues. Spray insulation, although effective for sealing gaps, can be more expensive and less practical for large, flat surfaces like basement walls compared to foam board. Therefore, for basement insulation, foam board provides the best combination of moisture resistance, thermal performance, and ease of installation.