If you’re finding that sitting close to your windows means feeling a draught in the air, or you have to add a few extra layers of clothing or turn up the heating, then it’s likely that your windows aren’t performing properly and are letting precious heat escape from your home.

There are many benefits to having energy-efficient windows – from reducing condensation to lowering energy bills and better soundproofing. However, having a new set of windows installed can be costly, which can lead to some homeowners just leaving their windows as they are. With a few tweaks, you can make your windows more energy-efficient and give them a new lease of life, without needing to replace them entirely. Here are our tips on how to get started.

Tips for improving energy efficiency with your windows

If you want to keep your heating costs low, having insulation and energy-efficient windows are very important. That said, if your windows are old, even investing in good insulation for your home won’t prevent them from leaking heat.

Sometimes replacing windows isn’t an option because of the cost, or because a property is listed. Keep reading to discover some energy-efficient hacks that can help your windows to perform better.

Tips for making windows more energy efficient homebrite

Trap heat with window shutters

If you have older windows in your property, getting some window shutters installed is a great option. Not only do they look aesthetically pleasing, but they can be completely or partially closed depending on your preferences and needs. It’s possible to purchase shutters with tight slats that allow for little air to pass between them, which helps to improve window energy efficiency.

Add insulation film to glass panes

It’s possible to purchase heat-insulating film that can be applied to both the internal and external sides of your window panes. This is a great hack for insulating windows and doesn’t cost much to do.

Just remember that it won’t be as effective at trapping heat when compared with properly re-glazed windows. But as a cheaper and more temporary solution, this can work well.

Seal any cracks and gaps

As windows age, cracks start to naturally appear, which comes as a result of natural movement, weather and other factors. Even hairline cracks can let air pass through. If you have wooden frames in particular, filling in even the smallest of cracks will improve energy efficiency. Older window frames can also warp and twist, and a previous poor window installation can cause gaps between the window cut-out and the frame, causing air to flow through.

Place your hand around the frame area and feel for gaps. A pencil torch will also help you to identify them. A good sealant will fill small gaps, while insulation tape will help to seal up larger ones. If the gaps are very large, this will only be a temporary solution, and you may need to invest in new windows or window frames in the future.

Get older windows re-glazed

This is a more expensive option, but may be necessary if you’ve tried insulation film with little success. By re-glazing your windows, you’re simply replacing your old glass panes. Double or triple glazing works best, but the latter can be costly. Most indoor heat escapes through the glass in windows via conduction, which replacement glass will prevent. Choose high-performance glass with low emissivity coatings, which reduce heat transfer through the glass, helping to keep your home cooler in the summer and warmer in winter.

Choose uPVC frames

Choose frames with low thermal conductivity, such as uPVC window frames, as they will help to prevent heat transfer and condensation, making your home more energy efficient. These will still require maintenance though, including sealing any cracks and gaps. Weatherstripping is a cost-effective solution for sealing gaps and enhancing the overall airtightness of your windows.

Install blinds

Installing thermal curtains, blinds or shades can help to provide an additional barrier against heat loss in winter and heat gain in summer. It can also help to lower your energy bills so that you save money in the long run, while providing a stylish aesthetic. If budget allows, you can install smart window controls like automated blinds to enable you to have more control over light and ventilation, maximising your energy savings.

Ensure regular maintenance

Regularly clean both the glass and window frames to remove dirt and debris. A build-up of dirt can reduce energy efficiency. Inspect window seals, weather strips, and replace anything that becomes damaged. Well-maintained windows will continue to provide optimal energy efficiency over time.

How do double-glazed windows save on energy?

Your average double-glazed window is made up of two sheets of glass with a 16mm gap between them. Air is trapped between the two glass panes, so that it’s unable to move freely through them (as it would with single-glazed windows). Single glazing causes heat to escape through the glass, but with double glazing, the gap between the panes is too small to allow the process of conduction, so the air gap slows down heat energy.

To make this gap in the double glazing even more efficient, the gap in the air space can be filled with Argon. This is a gas that provides good thermal performance and can also be great for soundproofing. Argon helps to slow down the movement of heat, which helps to trap heat in your home and prevent heat loss.

Double-glazed windows that are also carefully made to measure and fit the frame and window hole with precision are far more effective at trapping heat, and less draughty due to an airtight fit. Some homeowners with older properties worry that they won’t be able to have double glazing installed because they have older-style properties from the Victorian or Georgian eras. It’s possible to install double glazing in these types of homes, and even sash windows can be double-glazed to improve energy efficiency, helping you save on energy bills.

Why are energy-efficient windows important?

There are many reasons why energy-efficient windows are a great choice for your home.

Improving building efficiency

Energy-efficient windows help to reduce energy consumption. Windows that aren’t energy efficient can cause major heat loss, causing condensation and costly heating bills in order to maintain a comfortable indoor temperature. Energy-efficient windows are designed to minimise heat transfer, so that the temperature doesn’t fluctuate. As a result, you won’t use as much power to heat your home.

window condensation poor energy efficiency


As the world continues to be threatened by climate change and is acting to reduce its carbon footprint, energy-efficient windows are being prioritised more highly in new building design, as they trap heat in a building and lower energy consumption and bills. There is a growing awareness of environmental impact when it comes to selecting building materials, which is being driven by a demand to conserve energy.

Heating and powering homes account for 30% of total energy consumption in the UK. [1] In order to meet climate targets, the UK government also aims to ensure that all new homes built as of 2025 produce 70-80% less carbon emissions by including measures such as heat pumps and triple glazing.

Financial savings

Energy-efficient windows can save you money on your heating bills, as they won’t let as much heat escape, so you won’t need as much power to heat your home. While the outlay for installing new double-glazed windows might be significant, the reduced amounts of energy you’ll be using to heat your home will mean a return on your initial investment over time.

Double glazing can save you £235 per year on energy bills, and installing double-glazed windows can add up to 10% to the value of your home. [2]

Comfortable living

Aside from making your home warmer, energy-efficient windows contribute to noise cancellation, creating a quieter and more peaceful living environment. For those living in busier and more developed areas with increased road noise, this can mean a more pleasant and tranquil way of living, with better sleeping environments and less intrusion from traffic and environmental noise from the local area.

Energy-efficient windows also block out UV rays due to the coating that covers the glass panes. This coating helps to protect flooring, furnishings and artwork on the wall from fading and harmful UV rays, while still allowing natural light to pass through.


[1] What is the 2025 Future Homes Standard and How Will it Impact Residential Real Estate? – CBRE – https://www.cbre.co.uk/insights/articles/what-is-the-2025-future-homes-standard-and-how-will-it-impact-residential-real-estate

[2] Is it Worth Putting in Double Glazing? – The Eco Experts – https://www.theecoexperts.co.uk/windows/double-glazing