What Is A Good U-Value?

A U-value is a measurement for heat transfer that is applied to building components. This measurement represents how they conduct, or transfer heat. The U-value is calculated from the rate of energy transfer through one square meter of structure, divided by the difference in temperature at either side of that structure. As a U-value determines the rate of energy transferred, the lower the measurement, the more efficient the product is. This leads us onto a question we hear a lot, ‘What is a good U-value?’. The answer depends on the product in question.

ProductTypical U-value in W/m2K
Single Glazing4.8 – 5.8
Double Glazing1.2 – 3.7 (depending on type)
Triple Glazing<1

U-Values in Windows

There are two U-value measurements where windows are concerned, and it is very important to know which you are looking at.

  • Uw – This measures the U-value of the whole window, including the frame
  • Ug – This measures the U-value for the glass only (centre pane)

What can impact a new windows U-Value?

  • Single, double or triple glazing
  • Cavity size between each glass pane
  • Glass specification
  • Gas used between each glass pane
  • Type of spacer bar between glass panes
  • Frame material
  • Frame thickness
  • Number of chambers in the frame

The U-value of the overall unit is the most important measurement when deciding which windows you should install. This will give you the real-world performance of your windows and not just the glass.

How Important Is Energy Efficiency?

The word ‘crisis’ can often be overused. However, when it comes to the outlook energy bills, this word is unfortunately, very fitting. Experts suggest by Spring of 2023, the average household could be paying 500% more on energy than they were before the pandemic.

Previously, a solution to cost increases was to shop around and find a new supplier. Unfortunately, the current cost increase is widespread, meaning changing supplier will make little difference. The only solution to the increased costs is to become more energy efficient and stop using unnecessary energy. Becoming more energy efficient is a high priority to most, and it’s clear to see why.

A major source of heat loss in many homes is through the windows and doors. Sources suggest that you lose as much as 30% of your homes heat through your windows. The exact amount of heat loss depends on multiple factors, such as the age of your windows, specification and property type etc.

The increase in energy costs has rapidly increased the demand for new energy efficient windows. Previously, the average household would save enough money on their energy bills to pay for new windows after 19 years. Experts now predict that this will be slashed to only 9 years due to the accelerated energy cost increases.

With this in mind, energy performance has quickly become one of the primary factors when deciding if your home should benefit from new windows. Something important to note, is that not all windows and doors perform the same. Many windows and doors may look the same, but performance can differ largely depending on multiple factors.

How Can MPS Help?

At MPS, we have been committed to helping our customers for over 30 years. Although the reason why our customers install new windows may be shifting, our goal remains unchanged. Our goal always has, and always will be to provide our customers with the correct information and install the products that can benefit them the most.

Our staff have a wealth of knowledge within the industry, and we are here to help you understand which products can be most beneficial depending on what you want to achieve. Continuing to offer industry leading advice, products, quality of installation and aftercare ensure that there is no company more well versed to help you find the products best suited to you, and your requirements.



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