- Energy-efficient glazing reduces heat loss
- Better insulation against external noise
- Reduced condensation on inside of glass
- Helps to reduce your carbon footprint
- Keeps your property cooler in summer
Energy Ratings and 'U' Values Explained
What are 'U' Values?
'U' values measure how well a building material works as a thermal insulator. The lower the 'U' value the greater the performance in terms of how much energy is required to maintain a comfortable temperature within a property.
The calculation for measuring U-values are based on how effective a material is at preventing heat transmission. By measuring the time it takes for an amount of heat to travel between the inside and outside will determine the U-value.
What about energy ratings?
Energy ratings were introduced by the British Ratings Fenestration Council (BRFC) to give an overall rating that's better understood and recognized by consumers. Energy ratings not only take into account the U-value but also the solar gain and air leakage of a product, thus giving a clearer and more accurate reading.
Why is it important?
As energy prices continue to increase, the UK government have set out standards to which replacement windows and doors must conform. As of June 2022 it's been law that all replacement windows and doors in the UK must achieve a U-value of 1.4W/m²K or less.
These are controlled and regulated by various local authorities and government approved agencies such as the BFRC, Certass, Build-Check, FENSA and the GGF (Glass and Glazing Federation) Just Value Doors Ltd is registered and regulated by GGF www.ggf.org.uk/members/just-value-doors-ltd
How can I benefit?
Whilst every door and window we sell will already achieve a U-value of 1.4W/m²K or less, you have the option to upgrade further, and in turn benefit from a better insulated home.
At Just Value Doors we offer thermal upgrade and triple glazed options, which will both improve the thermal efficiency of your glass, increase the overall energy rating and improve the U-value.
Overall (glass & frame) Specification:
See below the various U Value (W/m²K) ranges applicable to our products. Note: You are presented with a more accurate U Value figure during customisation of the product, as some optional upgrades such as; thermal upgrade, triple glazing and thermal break will affect the overall rating.
Glass Specification:
Thermal & Triple | 28-36mm Unit
Low E/Warm Spacer/Low E/Warm Spacer/Std Float - 0.8 W/m²K*
Thermal only | 28mm Unit
Low-E/Warm Spacer/Low-E Film - 1.2 W/m²K*
Triple only | 28-36mm Unit
Low E/Std Spacer/Std Float/Std Spacer/Standard Float - 1.1 W/m²K*
Standard | 28mm Unit
Low-E/Std Spacer/Std Float - 1.3 W/m²K*
* Although all products meet the current legislation for all new build and replacement projects, the U Values and Energy Ratings stated above are for guidance purposes only and should not be relied upon. We recommend that if any specific certification documentation or similar is required for any product, this should be requested and reviewed before ordering. It is the customer's responsibility to ensure these documents meet their requirements before placing an order.
