R-value can be as high as up to which value?

R-value can be as high as up to which value?

• A. R-60
• B. R-20
• C. R-38
• D. R-12

Answer: (C)

R-value measures a material’s resistance to heat flow—the higher the number, the better the insulation. In typical residential construction, especially for ceilings or attics where you can add more insulation, you often see high but realistic values like R-38. The other numbers shown represent lower insulation levels, which would let more heat pass through. While even higher values can be achieved in specialized setups, R-38 is the highest commonly attainable value among these options in standard practice, making it the best choice for this question.

R-value measures a material’s resistance to heat flow—the higher the number, the better the insulation. In typical residential construction, especially for ceilings or attics where you can add more insulation, you often see high but realistic values like R-38. The other numbers shown represent lower insulation levels, which would let more heat pass through. While even higher values can be achieved in specialized setups, R-38 is the highest commonly attainable value among these options in standard practice, making it the best choice for this question.