ENERGY STAR® Qualifications for Fenestration Products
For ENERGY STAR, windows and doors are qualified for their energy efficiency by either a U-value or Energy Rating (ER) for each of the four Canadian zones. Skylights are qualified by their U-value only. The energy efficiency values were developed primarily for low-rise residential dwellings (three floors or less).
The following tables show the levels for each climate zone in Canada. The ratings given in the tables are for the entire product. Energy efficiency ratings for the glass portion only, often called "centre-of-glass" ratings, usually make the product appear more energy efficient than it really is.
Note: Effective October 1, 2010 the requirements are changing. The tables indicate the current requirements followed by the new requirements.
ENERGY STAR Requirements for Windows and Doors
Products may comply based on either their U-value and R-value or their Energy Rating
| Zone |
Maximum U-Values and Minimum R-Values |
Minimum Energy Rating (ER) Values (Maximum U-Value 2.00 W/m2•K) |
||||||
|---|---|---|---|---|---|---|---|---|
|
U-Value (W/m2•K) |
U-Value (Btu/h•ft.2•°F) |
R-Value (ft.2•h•°F/Btu) |
Most Windows and All Doors (includes fixed casement style windows) |
Picture Windows Only |
||||
| 1998 | 2004* | 1998 | 2004* | |||||
| A | 2.00 | 0.35 | 2.9 | or | –16 | 17 | –6 | 27 |
| B | 1.80 | 0.32 | 3.2 | or | –12 | 21 | –2 | 31 |
| C | 1.60 | 0.28 | 3.6 | or | –8 | 25 | +2 | 35 |
| D | 1.40 | 0.25 | 4.0 | or | –5 | 29 | +5 | 39 |
*The methodology used to calculate Energy Ratings, as defined by the Canadian Standards Association, was recently changed. Under the new 2004 standard, all windows and doors have positive ER numbers.
| Windows (Effective October 1, 2010) | |||||
|---|---|---|---|---|---|
| Zone |
Heating Degree-Day Range |
Compliance Paths | |||
| Energy Rating (ER) | or | U-Factor | |||
|
Minimum ER (unitless) Maximum U-Factor 2.00 W/m²•K (0.35 Btu/h•ft.²•°F) |
Maximum U-Factor W/m²•K (Btu/h•ft.²•°F) |
Minimum ER (unitless) |
|||
| A | <= 3500 | 21 | or | 1.80 (0.32) | 13 |
| B | > 3500 to <= 5500 | 25 | or | 1.60 (0.28) | 17 |
| C | > 5500 to <= 8000 | 29 | or | 1.40 (0.25) | 21 |
| D | > 8000 | 34 | or | 1.20 (0.21) | 25 |
| Doors (Effective October 1, 2010) | |||||
|---|---|---|---|---|---|
| Zone |
Heating Degree-Day Range |
Compliance Paths | |||
| Energy Rating (ER) | or | U-Factor | |||
|
Minimum ER (unitless) Maximum U-Factor 2.00 W/m²•K (0.35 Btu/h•ft.²•°F) |
Maximum U-Factor W/m²•K (Btu/h•ft.²•°F) |
Minimum ER (unitless) |
|||
| A | <= 3500 | 21 | or | 1.80 (0.32) | N/A |
| B | > 3500 to <= 5500 | 25 | or | 1.60 (0.28) | N/A |
| C | > 5500 to <= 8000 | 29 | or | 1.40 (0.25) | N/A |
| D | > 8000 | 34 | or | 1.20 (0.21) | N/A |
ENERGY STAR Requirements for Skylights
| Zone |
Maximum U-Value (W/m2•K) |
Maximum U-Value (Btu/h•ft.2•°F) |
Minimum R-Value (ft.2•h•°F/Btu) |
|---|---|---|---|
| A | 3.10 | 0.54 | 1.8 |
| B | 2.80 | 0.50 | 2.0 |
| C | 2.60 | 0.46 | 2.2 |
| D | 2.38 | 0.42 | 2.4 |
| Skylights* (Effective October 1, 2010) | ||
|---|---|---|
| Zone |
Heating Degree-Day Range |
Maximum U-Factor W/m²•K (Btu/h•ft.²•°F) |
| A | <= 3500 | 2.80 (0.50) |
| B | > 3500 to <= 5500 | 2.60 (0.46) |
| C | > 5500 to <= 8000 | 2.40 (0.42) |
| D | > 8000 | 2.20 (0.39) |
*includes Tubular Skylights
U-Factor Conversion to R-Value
Windows, doors and skylights are not normally assigned an R-value when tested. To help you better understand their insulating performance, sample U-factors in both metric and imperial units have been converted to R-values in the table below. Because Energy Rating values are derived from a formula that uses both U-factor and solar heat gain, there is no method to directly convert the Energy Rating value to R-value.
| U-Factor Conversion to R-Value | ||
|---|---|---|
|
U-Factor W/m²•K |
U-Factor Btu/h•ft.²•°F |
R-Value ft.²•h•°F/Btu |
| 3.40 | 0.60 | 1.7 |
| 3.20 | 0.56 | 1.8 |
| 3.00 | 0.53 | 1.9 |
| 2.80 | 0.50 | 2.0 |
| 2.60 | 0.46 | 2.2 |
| 2.40 | 0.42 | 2.4 |
| 2.20 | 0.39 | 2.6 |
| 2.00 | 0.35 | 2.9 |
| 1.80 | 0.32 | 3.2 |
| 1.60 | 0.28 | 3.6 |
| 1.40 | 0.25 | 4.0 |
| 1.20 | 0.21 | 4.8 |
| 1.00 | 0.18 | 5.6 |
| 0.80 | 0.14 | 7.1 |
| 0.60 | 0.11 | 9.1 |
Airtightness and Other Ratings
All windows and sliding glass doors must be rated for their airtightness, watertightness, wind load strength, resistance to forced entry, insect screen strength (windows only) and ease of operation (sliding glass doors only) when they are installed in new homes or buildings. Provincial/territorial and local building codes require different airtightness, watertightness and window load strength categories depending on the climatic conditions.
All ENERGY STAR qualified sliding glass doors and operable windows must have at least an A2 for airtightness. Picture windows must receive a "Fixed" rating. The following table shows the range for each product type.
Airtightness Categories – Windows and Sliding Glass Doors
| Type | Least Airtight | Most Airtight |
|---|---|---|
| Most operable windows | A1 | A3 |
| Single-hung windows* | A1/Fixed | A3/Fixed |
| Single sliding windows* | A1/Fixed | A3/Fixed |
| Non-operable (fixed) casement windows | A1 | A3 |
| Picture windows | Fixed (pass/fail rating) | |
| Sliding glass doors | A1 | A3 |
*Operable and non-operable sashes may be tested and rated separately for single-hung and single sliding windows.
There are no minimum requirements for ENERGY STAR for the other categories. The following table shows the ranges for each product type.
Other Categories – Windows
| Test | Lowest Category | Highest Category |
|---|---|---|
| Watertightness | B1 | B7 |
| Wind load strength | C1 | C5 |
| Insect screen strength* | S1 | S2 |
| Resistance to forced entry | F10 or F1 | F20 or F2 |
*This test measures only how well the screen mesh stays fastened to the screen mesh frame, not how well the insect screen stays fastened to the window frame. Most insect screens are designed to be easily removeable from the window to allow for egress in case of an emergency. An S1 rating is normally adequate for residential applications.
Other Categories – Sliding Glass Doors
| Test | Lowest Category | Highest Category |
|---|---|---|
| Watertightness | B1 | B4 |
| Wind load strength | C1 | C3 |
| Ease of operation | E1 | E3 |
| Resistance to forced entry | F1 | F2 |
Note: Insect screen strength, resistance to forced entry and ease of operation ratings are not available in the ENERGY STAR qualified model listings.
The ENERGY STAR name and symbol are administered and promoted in Canada by Natural Resources Canada and are registered in Canada by the United States Environmental Protection Agency.