What is thermal window film? Experts reveal how to save over £70 per year on your heating for less than £15

We may be on the right side of Christmas if your sights are set on summer, but unfortunately, cold weather is upon us for the next few months. With consistently low temperatures, it doesn’t feel like the thermostat will be turned down any time soon, but experts have revealed that adding window film to your windows can help retain heat in your home and even save you money on heating bills.

Energy bills seem to be ever-rising, meaning the need to find ways to save energy at home is greater than ever. At Ideal Home we’re dedicated to finding you the best heating advice to keep your home warm and bills within budget.

Adding window film to your glass adds a bonus thermal layer which retains heat and reduces draughts and heat loss. Experts even say it can save you up to £73.66 on your annual energy bill - this is everything you need to know.

What is window film?

Window films are thick laminate materials with insulating properties and can reduce a window’s heat loss by 33%, according to a report by EvoWrap. The research also revealed consumers could save £73.66 on their yearly heating bill from fitting window film.

Window films are pretty easy to install at home and something an inexperienced DIY-er would be able to achieve. EvoWrap recommends cleaning your windows first, as well as cutting your film to the correct size of your window.

Then all you need to do is remove the liner on the back of the film and stick the wrap to your window. It has a strong adhesive which means the film should stick to the glass easily. You should use a squeegee to iron out any bumps or bubbles in the film. A bit like a phone screen protector, you shouldn't be able to notice the film on the glass when complete.

Window film is a relatively cheap form of insulation to install too, it can cost less than £15 to pick up in DIY and hardware stores. I spotted tesamoll Thermo Cover Window Insulating Film for £13.13 on Amazon, and Stormguard’s Secondary Glazing Window Film is just £10 at Dunelm. When you take into consideration the large savings to be had, investing in window film feels like a complete bargain.

Does thermal window film work?

According to experts, thermal window film can make a difference and help insulate your home. ‘When it comes to keeping your home warm without cranking up the heating, window films are a brilliant, often underrated solution. Their insulating properties are designed to reduce heat transfer and add an extra layer of insulation to your windows, which are typically one of the main culprits for heat loss in a home,’ explains Fiona Peake, money-saving expert at Ocean Finance.

‘In winter, they help by reflecting the heat from inside your home back into the room, rather than allowing it to escape through the glass. If you’ve felt a chill when sitting near a window, especially single-glazed ones, window films can help reduce that icy draft and make your home cosier.

‘In summer, window films can be used to reflect sunlight and heat away, keeping your home cooler. They can also improve privacy in your home, and help to block harmful UV rays which can fade your furniture, carpets, and curtains over time.’

Why can it save on energy bills?

‘Window film acts as a thermal barrier, slowing down heat transfer through the glass. This means that cold air takes longer to enter, and warm air takes longer to escape,' explains Sam Tamlyn, Window Expert and Managing Director of The Shutter Store.'Furthermore, depending on the type of glazing you may have, window film helps to improve your window's insulating properties, acting as a much cheaper and practical alternative to a full window replacement that may cost you hundreds.’

Your windows are responsible for up to 20% of your home’s heat loss, which is why it’s important to focus on insulating your glazing. What’s more window film or secondary glazing reduces condensation, making it a worthy investment if you're also tackling damp, mould and condensation.

‘If you have single-glazed windows, the impact will be more noticeable, as these lose heat far quicker than double or triple-glazing. While window films won’t turn single glazing into double glazing, they can act as a cost-effective workaround, particularly if you’re looking for a quick fix to tackle drafts and heat loss,' says Fiona.

'For double-glazed windows, they can still make a difference by cutting down on the heat that escapes. Combined with other measures like draught-proofing and using thermal curtains, window films can help you stay cosy while keeping costs down.'

Heat escaping from windows is a big problem if you're looking to save on bills. Taking measures such as adding thermal blinds is another way to cut costs and the perfect pairing for window film to keep the heat in and cold out.