Insulation R-Value Calculator
Use this insulation r-value calculator to estimate insulation R value or layers. Enter material R value, thickness and layer details and review combined or required insulation R value.
Simple series sum; does not account for thermal bridging through framing, which lowers effective real-world R-value somewhat.
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How it works
Total R-value = sum of each layer's R-value (layers in series add directly)How to use the Insulation R-Value Calculator
Start by entering material R value, thickness and layer details. Keep the units consistent and check that each value belongs to the same question.
The result gives combined or required insulation R value. Product performance and climate requirements vary by location. Use it as a guide and check any instructions, rules or professional advice that apply.