RSI (metric R) to U-value
Type a value in RSI to get it in U instantly.
0.05U
That's 2× as insulating as passive house insulation — nothing on our list beats it. That is a U-value of about 0.05 W/m²·K.
Convert the other way: U to RSI
What it means
How well does it insulate?
R-values here are for the material alone. Real walls lose extra heat through studs, gaps and joints.
The math
How to convert RSI to U
R-value and U-value are reciprocals: U = 1 ÷ RSI, and RSI = 1 ÷ U. A high R insulates well; a high U does not.
Example: 20 RSI = 0.05 U.
Every unit
Your insulation in every unit
Tables
RSI to U conversion table
| RSI | U |
|---|---|
| 1 RSI | 1 U |
| 2 RSI | 0.5 U |
| 3 RSI | 0.333333 U |
| 5 RSI | 0.2 U |
| 8 RSI | 0.125 U |
| 11 RSI | 0.0909091 U |
| 13 RSI | 0.0769231 U |
| 15 RSI | 0.0666667 U |
| 19 RSI | 0.0526316 U |
| 21 RSI | 0.047619 U |
| 30 RSI | 0.0333333 U |
| 38 RSI | 0.0263158 U |
| 49 RSI | 0.0204082 U |
| 60 RSI | 0.0166667 U |
U to RSI conversion table
| U | RSI |
|---|---|
| 1 U | 1 RSI |
| 2 U | 0.5 RSI |
| 3 U | 0.333333 RSI |
| 5 U | 0.2 RSI |
| 8 U | 0.125 RSI |
| 11 U | 0.0909091 RSI |
| 13 U | 0.0769231 RSI |
| 15 U | 0.0666667 RSI |
| 19 U | 0.0526316 RSI |
| 21 U | 0.047619 RSI |
| 30 U | 0.0333333 RSI |
| 38 U | 0.0263158 RSI |
| 49 U | 0.0204082 RSI |
| 60 U | 0.0166667 RSI |
Quick answers
Quick answers
- How many U is 1 RSI?
- 1 RSI is 1 U.
- How many U is 10 RSI?
- 10 RSI is 0.1 U.
- How many U is 20 RSI?
- 20 RSI is 0.05 U.
The units
About these units
RSI (metric R) (RSI)
The metric resistance: square meter-kelvins per watt. Used everywhere except the US.
U-value (U)
The inverse: heat lost per square meter per kelvin. Windows and building codes use it, and lower is better.
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