Glossary · Insulation & windows
RSI (metric R-value)
Also called: RSI value · m²·K/W
The metric version of R-value used in Canada; multiply RSI by 5.678 to get R, so RSI 8.8 is about R-50.
What it means
RSI measures the same thing as R-value, resistance to heat flow, but in metric units (square metre kelvins per watt). Canadian building codes, product labels and EnerGuide reports often give RSI first. Because the numbers are smaller, RSI 3.5 can sound weak, but it's about R-20.
Why it matters in an audit
Converting your existing RSI and the recommended level into the same units tells you how much insulation to add.
Typical numbers
Reference values with their sources. Your energy advisor’s report gives the figure for your own house.
| What | Value | Source |
|---|---|---|
| Conversion | R = RSI × 5.678; RSI = R ÷ 5.678 | natural-resources.canada.ca ↗ |
| Examples | RSI 3.52 ≈ R-20; RSI 8.8 ≈ R-50; RSI 10.43 ≈ R-59 | natural-resources.canada.ca ↗ |