A U-value is one of the main measures you might come across when comparing the thermal performance of new windows and doors. While the terminology can sound technical, the basic principle is straightforward: the lower the U-value, the better the product is at limiting heat transfer.
Reducing unnecessary heat loss can help you maintain a more comfortable home and reduce the energy required for heating.
What Is a U-Value and How Is It Measured?
A U-value measures the rate of heat transfer through a building element, such as a complete window or door. U-values are expressed in W/m²K (watts per square metre kelvin). Homeowners should look at the performance of the complete window or door, rather than glazing or frame performance in isolation.
Why U-Values Matter for Aluminium Windows
Modern aluminium windows differ greatly from earlier systems, which didn’t necessarily incorporate today’s thermal-break technology.
Modern Endurance aluminium products feature InsuLock multi-chamber thermal break technology, designed to reduce heat transfer through the frame.
Glazing works alongside the frame to determine the overall thermal performance of the window. Endurance Aluminium windows can achieve U-values as low as 1.4 W/m²K with double glazing, with triple-glazed options reaching as low as 1.0 W/m²K, depending on the system.
Improving Your Home’s Thermal Performance
If your existing windows are old or poorly performing, replacing them with modern thermally efficient systems can help reduce heat loss. When choosing new windows, consider the whole specification, including frame construction, thermal breaks, glazing and installation.
Double or triple glazing may be appropriate depending on the product and required level of performance. Double and triple glazing are available across much of the Endurance Aluminium range.
Reducing heat loss can mean less energy is required to maintain a comfortable indoor temperature, potentially reducing heating requirements. However, the impact on your energy bills will also depend on factors such as your property, insulation, heating system, energy prices and how your home is used.
Understanding the Numbers
When comparing replacement windows, a lower U-value indicates better resistance to heat transfer. Be sure to ask installers about the U-value of the complete product you’re considering, rather than concentrating solely on the glazing.
Looking for more thermally efficient windows? Explore the Endurance Aluminium window range today to find out more about our offerings.
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