Insulation Calculator
Estimate added R-value, layers, coverage, package count and material cost for an editable wall, floor or attic assembly.
What Is the Insulation Calculator?
The Insulation Calculator converts an assembly target into a purchase estimate. It subtracts openings, compares existing and target R-values, calculates the number of product layers required, adds waste and rounds coverage up to whole packages with a cost summary.
How It Works
Enter the insulated area and openings, then record the existing R-value, target R-value and R-value delivered by one layer of the chosen product. Use the coverage and price printed on the exact package.
When to Use It
Use it to compare preliminary insulation options for walls, floors, ceilings and accessible attics. Effective whole-assembly performance can be lower because of framing, compression, gaps, moisture and thermal bridging.
Frequently Asked Questions
- Can I Simply Stack R-values?
- Layer R-values are approximately additive when installed correctly, but framing and gaps reduce whole-assembly performance. Do not compress products beyond their rated installation.
- Which Target R-value Should I Use?
- Targets vary by climate zone, assembly and local energy code. Confirm the required value before buying material.
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