Wall insulation refers to materials installed within wall cavities, externally, or as continuous layers to reduce heat transfer through building walls and improve thermal performance. Wall insulation is critical for maintaining indoor temperatures, reducing heating and cooling loads, and improving energy efficiency across residential and commercial buildings.
Types and R-Values
Common wall insulation includes fiberglass batts (R-3.2 to R-3.8 per inch), mineral wool (R-3.2 per inch), spray foam (R-3.6 to R-6.5 per inch), and rigid foam boards (R-3.8 to R-6.5 per inch). Typical wall assemblies target R-13 to R-21 depending on climate zone. Proper installation without gaps or compression is essential for achieving rated R-values.
Performance and Considerations
Wall insulation reduces heating and cooling energy consumption by 15-25 percent. Installation costs range from $1.50-4.00 per square foot depending on material and method. Moisture management and air sealing are critical to prevent condensation and maintain insulation effectiveness over time.