R-value describes resistance to conductive heat flow. It is useful for comparing insulation levels, but it does not tell the entire story: gaps, compression, wind washing, air leakage and moisture can all reduce real-world performance.
Attic targets and rebate thresholds
For current Focus on Energy attic-insulation rebates, existing insulation conditions determine the minimum improved level. The program states that R-19 or less must be improved to R-38 or greater, and existing R-20 through R-38 must be improved to at least R-49.
Wisconsin code context
Wisconsin's dwelling-code insulation provisions include specific ceiling and attic requirements. The exact requirement depends on the assembly and project type, so a contractor should verify the code that applies to the work rather than relying on a generic chart.
Installation quality matters
- Batts should fill cavities without compression, folds or gaps.
- Loose-fill needs uniform installed depth and protection from wind washing near eaves.
- Air sealing should address penetrations that allow conditioned air to bypass insulation.
- Attic ventilation paths should remain open where the roof design requires them.
Not sure what your attic has now?
Request an evaluation and ask the contractor to document existing insulation and proposed finished R-value.
Request an EstimateFrequently asked questions
What R-value does Focus on Energy require for qualifying attic improvements?
Current program requirements vary based on existing insulation. Existing R-19 or less must generally be improved to at least R-38, while existing R-20 to R-38 must be improved to at least R-49 for the attic measure.
Is a higher R-value always better?
Higher R-value increases resistance to heat flow, but the assembly also needs good air control, moisture management and correct installation. Gaps or air leakage can undermine performance.
Can I measure attic R-value by depth?
Depth charts can provide an estimate when the insulation material and installed condition are known, but compressed, mixed or settled material makes visual estimates less reliable.