Single-Glazed Window
vs
Double-Glazed Window
Window Insulation Comparison
Graph of Temperatures Recorded Under
2 Different Window Insulations
set ‘Single-glazed Window’ as baseline/existing window
Graph of Temperatures Difference Between
2 Different Window Insulations
set ‘Single-glazed Window’ as baseline/existing window
Legend
Blue – Double-glazed Window
Orange – Single-glazed Window
During Daytime
Temperature record orders: Double-glazed Window ≥ Single-glazed Window
For hot regions: a double-glazed window retains more heat in a longer period than a single-glazed window on a hot day (up to 19°C higher).
For cold regions: in contrast, a double-glazed window can keep the room warmer for a longer period than a single-glazed window, which is definitely good news.
During Nighttime
Temperature record orders: Double-glazed Window > Single-glazed Window
For hot regions: a double-glazed window retains more heat than a single-glazed window (up to 8°C higher).
For cold regions: in contrast, a double-glazed window can keep the room warmer for a longer period than a single-glazed window, which is definitely good news.
Cost-wise
Double-glazed window replacement could be very expensive.
The replacement involves works, such as removing existing windows and window frames, manufacturing double-glazed windows off-site, and transporting them to the site, which are labour intensive and time-consuming.
Other Factors
Acoustic Performance: a double-glazed window has much better noise control than a single-glazed window.
Buildability: it might not be ideal to replace windows in large buildings if just for energy efficiency purposes.
Sustainability: as stated above, considerable waste is produced during the replacement process.