Rising energy costs are a major concern for homeowners across the country. It’s no wonder why so many people are looking for ways to upgrade the energy efficiency of their home. Many homes are losing heat through their windows, especially older homes where frames and glazing may have deteriorated.
Replacing windows with modern, energy-efficient versions is a great investment to help improve insulation and reduce heating demand. Haus Installations brings you a guide on how to reduce your energy bills with new windows, explaining the different options available to maximise comfort and save you money.
Why Windows Play A Key Role in Energy Efficiency
Heat loss throughout a home can occur via many different features, and windows are a major contribution to overall heat loss.
Heat can naturally escape through glazing, gaps around the frame and within the window unit itself. Older windows will also likely have degraded seals and older glazing that don’t have the same modern coatings or gas fills that improve energy efficiency.
Replacing your home’s windows with modern versions will enhance energy efficiency, reduce heat loss and help maintain a more consistent indoor temperature.
How Double Glazing Helps Reduce Energy Bills
New windows can be fitted with double glazing. While it has been around for several decades, older double glazing now simply can’t offer the same benefits as modern versions.
Reducing Heat Loss
Modern double-glazed windows feature two panes of glass separated by a space bar, with wider cavities of 16-20mm slowing down heat transfer. The gap is filled with air or inert gas, both of which are poor conductors of heat. Modern double glazing will also have low-E coatings, which reflect heat back into the room, further minimising heat loss.
Comfortable Temperatures All Year-Round
Because double glazing reduces heat loss significantly, your home will benefit from fewer cold spots near the windows, helping to create more consistent indoor temperatures. It’s especially valuable during winter, as warm indoor air won’t escape easily, while the hot air outside during the summer will be slow to enter the home.
Less Need For Heating
The design of double glazing is made to improve insulation, and therefore contribute to lower energy bills. The wide gap filled with dense argon gas drastically slows down heat transfer.
For example, in the winter you might turn on your heating in the morning for a few hours to warm up the home, and then you can turn it off and benefit from the insulating power the double glazing provides. You won’t be so reliant on central heating like you were before, helping to contribute to lower heating bills.
Choosing Energy Efficient Window Frames
Modern windows often use uPVC, aluminium and composite materials for the frame, as these are ideal insulating materials and provide options to suit different budgets and visual preferences.
uPVC Windows
UPVC windows are a very popular choice for many homeowners because they are the most affordable. While uPVC is cheaper, it still provides excellent thermal efficiency, thanks to the multi-chambered frame structure, which further slows down heat transfer. Window frames made of uPVC are also very low maintenance, and to have consistent thermal efficiency, the rubber weather seals can be lubricated every few months to prevent air gaps.
Aluminium Windows
Aluminium is another ideal material option for windows that reduce energy bills. Known for their slim sightlines and contemporary appearance, aluminium frames can maximise the amount of natural light entering a home without compromising strength. While aluminium naturally conducts heat more readily than uPVC, modern aluminium windows are designed with thermal break technology, which creates a barrier between the inner and outer frame sections to reduce heat transfer.
As a result, high-quality aluminium windows can deliver excellent thermal performance while offering a sleek, durable and low-maintenance solution for modern homes.
Composite Windows
Composite windows are designed to combine the benefits of multiple materials, typically using a timber interior with an aluminium exterior. This construction provides excellent insulation from the timber while benefiting from the durability and weather resistance of aluminium on the outside. Composite frames are often chosen by homeowners seeking a premium performance, as they offer impressive thermal efficiency, long-lasting durability and an attractive appearance.
Although they are generally more expensive than uPVC or aluminium alternatives, composite windows can be a worthwhile investment for those prioritising energy efficiency and longevity.
Don’t Overlook Draughts and Seals
Even the most energy-efficient windows can lose performance if draughts and damaged seals are not addressed. Over time, weather seals can deteriorate, shrink or become damaged, allowing unwanted air movement around the window frame. These gaps can increase heat loss during winter and make it harder to maintain a comfortable indoor temperature.
Common signs of failing seals include:
- Noticeable draughts near windows
- Condensation between glazing panes
- Rattling frames
- Rising energy bills
If these issues are left unresolved, they can reduce the effectiveness of the window and place greater demand on your heating system. Older homes with windows that have been in place for 20+ years are most likely to have these recurring issues.
For replacing the old with the new, professional installation is essential for achieving the best thermal performance. Correctly fitted windows help eliminate gaps around the frames and ensure seals perform as intended. Regular inspections and simple maintenance, such as cleaning and checking the weather seals, can help keep windows operating efficiently and protect their energy-saving benefits for years to come.
Additional Ways to Improve Window Insulation
Add Glass Treatments
If you’re looking to truly improve energy and thermal efficiency for your windows, there are several glass treatments you can choose.
- Window insulation film:
This is a cost-effective option that can be applied directly to the glass to create an additional insulating layer. Insulation film helps reduce heat transfer and can improve the overall performance of older windows. - Thermal or cellular blinds:
These are designed with pockets that trap air, creating a barrier between the room and the window to improve insulation. They can also help reduce glare and increase privacy without sacrificing natural light. - Thermal lined curtains:
Thermal lined curtains provide another effective way to improve window insulation. The additional lining helps reduce draughts and heat loss around the window area, while also helping to keep rooms cooler during warmer weather.
Secondary Glazing
While double glazing is a great option for energy-efficient windows, not everyone has the budget to include it, either to replace older glazing or for an entire window replacement.
There is a cheaper option known as secondary glazing, which is a fully separate pane of glass or transparent plastic fitted to the internal side of an existing window. It’s a non-invasive way of increasing thermal insulation, reducing external noise and adding another layer of security if you’ve only got existing windows with single glazing.
Other Benefits of Energy-Efficient Windows
On top of being highly energy efficient and helping to reduce your energy bills, there are other wider benefits gained with replacing your old windows.
- Improved comfort:
Because warm air will be kept in during the winter and hot air kept out during the summer, you’ll benefit from a more comfortable home when it comes to temperature. There’ll be less cold spots around your windows, reducing draughts and keeping temperatures stable. - Reduced condensation:
A professional fit where window seals are tight will stop and reduce condensation from occurring inside, between and on the outside of the panes. Frequent condensation is a typical sign of poor ventilation and can lead to mould growth or damage to window frames. If condensation is forming between the panes of a double-glazed window, it usually indicates a failed seal, which is allowing the insulating gas to escape, reducing energy efficiency. - Noise reduction:
Double glazing can help reduce the amount of external noise entering a property by creating an additional barrier between your home and the outside environment. This can be hugely beneficial for homes located near busy roads, schools or other areas with high levels of noise pollution. - Enhanced aesthetics:
Modern windows can significantly improve the appearance of a property, both inside and out, by providing clean lines and contemporary designs. With a wide range of frame materials, colours and finishes available, homeowners can choose windows that complement the style and character of their home.
When Should You Consider Replacing Your Windows?
It may be time to replace your outdated and poorly insulated windows with new, energy-efficient ones. If you are consistently facing draughts, condensation, difficulty opening and closing your windows, have damaged frames or are seeing an increase in heating costs, Haus Installations can provide local, professional window replacement in Worcester and the surrounding areas. Get a pressure-free quote from us and let us help you reduce your energy bills.
Frequently Asked Questions
How much energy do new windows save?
Replacing single-pane windows with modern, A-rated double glazing can reduce heat loss through windows by up to 50%. Depending on the age and condition of your existing windows, upgrading to energy-efficient glazing could help reduce household energy bills by around 10% to 20%.
What type of window frame is most energy efficient?
Aluminium, uPVC and composite window frames can all provide excellent thermal performance when properly designed and installed. The most energy-efficient option will depend on the window’s overall construction, glazing specification and the quality of installation rather than the frame material alone.
