How Energy Efficient Are New Windows?

Energy costs have surged to unprecedented rates in the UK recently. This has had a huge impact on homeowners and energy bills are therefore a very hot topic. The October price caps have been released and although this has reduced the cost of energy per unit, it is still exponentially higher than it was at the start of 2022. The energy cost crisis has forced millions of UK homeowners to question how they can make their homes more energy efficient. The most popular question we are now being asked by our customers is ‘How Energy Efficient Are New Windows?’

Rising gas and electricity prices

Sources suggest that you could be losing as much as 30% of the heat from your home through your windows. The exact amount of heat loss depends on many factors such as the specification and age of your windows, property type etc. A high rate of heat loss, coupled with increased energy costs has rapidly increased the demand for new energy efficient windows. It used to be that the average household would save enough money on their energy bills to pay for their new windows after 19 years. Experts now estimate that this will be slashed to only 9 years due to the recent cost increases.

With this in mind, it’s no wonder that energy performance is one of the most important factors when deciding if your home should benefit from new windows. It is important for homeowners to be aware that not all windows and doors perform the same. Many windows and doors may look the same, but the performance can differ largely depending on multiple factors.

Window efficiency rating

What Can Affect The Energy Performance Of New Windows & Doors?


Glass covers the largest surface area of almost all windows and doors that are installed. For this reason, it has a massive impact on the overall energy efficiency. As standard, MPS do not install any new window or door with a glazing energy rating any lower than ‘A’. This is achieved by using the latest innovations within the glazing industry for both our double and triple glazed units. The use of argon gas, warm edge spacer bars and low emissivity glazing have had a great impact on the energy performance of modern sealed units.


Glass is not the only important factor when it comes to energy efficiency. The material, construction and depth of the frames also has a huge impact on the performance. Naturally, uPVC is a better insulating material when compared with aluminium, so our uPVC frames are highly efficient. Aluminium conducts more heat, so we use a thermal break to help keep the cold outside, and the warm inside. Window frames differ internally, and a high thermal efficiency is achieved by using a multi chambered profile to ensure that less heat escapes from your home. Also, a deeper frame from front to back will allow more chambers and further increase thermal performance. All profiles of windows and doors will have a different energy rating, even if they look the same. Fortunately, our experts are on hand to help explain the differences and help you understand what product best suits your needs.


A windows efficiency is only relevant if it is surveyed and installed to a high standard. If a window is manufactured too small and made to fit the aperture, this will lead to poor insulating properties and the window may seem draughty. Equally, if a window has not been finished and sealed to the correct standard then this will have an adverse effect on the performance. We have seen many high quality items installed poorly which has led to unwanted draughts and even water ingress. At MPS, we understand the importance of survey, installation and aftercare. We always ensure that the required time, effort and planning are taken. This ensures you not only have a market leading product, but market leading installation and aftercare too.

Double Glazing or Triple Glazing?

Modern double or triple glazed units both offer significant improvements over single glazing or even older double glazed units. 

The differences between double and triple glazing are simple. Double glazed units consist of 2 panes of glass which are separated by gas. Triple glazing simply adds an additional pane of glass to the unit. The additional pane of glass, coupled with a larger cavity provides more insulation, therefore less heat can escape your home. Triple glazing however, does come at a higher financial cost.

Whilst the additional pane of glass aids heat loss, it also lowers the amount of the sun’s energy that can pass through the window. This leads to a trade-off between heat lost through the window, versus heat that can be gained from the sun. With this in mind, the best solution is not always as easy as ‘should I choose double or triple glazing’. Sometimes a more tailored approach is required. Choosing high specification double glazing units for south facing or warmer parts of the home could be your best option. For north facing or colder rooms triple glazing may be more appropriate when the main goal is energy efficiency.

Advantages of Triple Glazing

  • Greater for heat efficiency
  • Enhanced noise reduction
  • Minimises areas of hot & cold in the home
  • Better for minimising condensation
  • Makes the window more secure
  • Initial outlay more expensive but more effective longer term

Advantages of Double Glazing

  • Lower purchase cost
  • Higher solar gain
  • Lighter windows mean less strain on the hinges & corner joints
  • Triple glazing without a toughened centre pane can have issues with cracking due to temperature differences, toughened glass is preferable but more expensive

How Much Do Energy Efficient Windows Cost?

Providing an answer to this question is very tricky as there are many factors that can affect the price. The size of your home, number of windows, size of the windows, material and specification all affect the overall cost. 

If you want to beat the energy cost increases by making your home more efficient, click the button below.



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