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Last updated: 20 May 2024

Window Insulation Film: Does It Really Work & Keep Out Cold?

Insulation film.

Windows are absolutely critical to the aesthetics of your property and, of course, to the mental and physical health of the home’s occupants. However, no matter how essential they are, they do create some problems for the heat retention of your home, with a huge amount of heat loss generated from them.

Now, double-glazed windows do possess much better thermal properties than a single pane window, but even double-glazed windows need a helping hand for insulation, and that is where window insulation films step up. Window films have been around for some time, and originally window films were used in commercial settings, before being fine-tuned for the residential house.

In this guide we’re going to explore the key questions surround window film, and whether something as small as a window film can make a big difference to the insulation of your property!

Does window insulation film really work?

In short, yes, window film really does work. Although window film isn’t magic, and if your windows suffer from air-leak problems or the insulation in your house isn’t up to a good standard, window film won’t solve your heat retention problems.

If your house insulation is to a good standard, and your windows too, then window film will definitely provide that added layer of thermal insulation that will make a massive difference in the comfort of your home. However, window film not only benefits the comfort of your home but also energy costs, with better heat retention in your home leading to less wasted energy and reduced energy bills each week.

Additionally, most types of window film also provide protection from harmful UV rays in the summer months, giving you peace of mind that you can relax in the sunshine without worrying about UV rays. (Regularly cleaning windows is another great way to maintain your window health and help them work more efficiently).

Insulation film can really increase a whole host of positives in your abode, something which we’ll delve into deeper in a later section.

Does window film keep cold out?

Window film has a dual purpose for different times of the year. Primarily, insulation window film is installed to keep the warmth inside your home by reducing the amount of heat lost through the transparent glass pane window, however, in the summer it also helps to keep rooms cool by reducing the heat from sunlight into your home.

The heat transfer from your radiators and fireplaces all contribute to the warmth in your home, so it’s a real issue when a lot of it is lost through your glass windows. Window film insulation prevents that heat from escaping for forming another seal on your windows, projecting the heat flow back into the room.

This is great for sash windows and more modern windows alike, its great for preventing the loss of heat through the glass pane window in your windows regardless of whether they are single or double glazing windows. Window films are a cost-effective and easy to install option to increase the insulation and heat retention in your home, and most are either installed with 3m double-sided tape or by simply sticking them straight to your windows with a safe adhesive provided with the insulating window film.

How much does window film help?

There are a ton of benefits to be enjoyed from window film, and we’re going to explore them a little more in separate sections here with some more detailed information for you to consider:


Aesthetic versatility

There is absolutely nothing to fear from insulating window film in terms of ruining the aesthetics of your home. In a bygone time, window films were generally reflective foil-like materials that reduced visibility and looked a little strange, however, the technology surrounding insulating window film has ensured that there are many different variations of window film from reflective to completely transparent options. Appearance is important for your home, and you shouldn’t have to compromise on product quality or appearance.

UV Protection & glare reduction

Insulation window film has some wonderful UV protection from harmful sun rays. This may not seem like a huge benefit, but if you have small children that like to play inside, you want to know that every precaution possible has been taken to ensure their safety. Similarly, window film insulation reduces the amount of glare on TV and computer screens to solve any technology usability problems you may have. These are features of window film that you can stick on glass which still doesn’t impede the appearance of your windows.

Energy saving & bill reduction

One thing that insulating window film can really help you save money on, is your energy bills and your overall energy costs throughout the year. The energy savings are generated by reducing the amount of warmth lost through your glass pane window and increasing the overall insulation of your home. Considering insulation window film is so cheap, this is an investment that will pay for itself very quickly.

Best insulation window film products

We’re now going to explore the best window films on the market, some information about them and the industry, and what makes them a top choice for thousands of people across the world.

Stormguard conservatory glazing window insulation film

The first item up is the Stormguard Conservatory Glazing Window Film. Stormguard are industry leaders in insulation window film and window films in general as is reflected in the reviews from this product and many others.

Now, this item, which is the full kit for insulating the glass in your conservatory, is incredibly easy to install and the appearance of the kit will leave you more than satisfied. You simply clean the windows with a white spirit, apply the 3m double-sided tape to the edges and attach to the window, and then use a hair dryer to bond the film to the window, albeit in a temporary state.

One of the best features of this item is how undetected the window film is once attached properly. You maintain complete clarity with your window glass, and you can install it in your conservatory, living room or any room in your house with windows! This item has garnered a respectable star rating of 3.9 out of 5, which is a great score considering it has had almost 2,000 reviews to date!

Customers seem to be responding well to the features of the Stormguard system, and a lot of them report that cold drafts and temperature issues are a thing of the past. The Stormguard systems can be found in abundance on many a UK based website, and you can click through their entire range of stock to explore it fully and read all the product info.

Duck indoor window shrink film insulation kit

Much like the Stormguard, the Duck window shrink film can be found on site after site, and it has also received a lot of attention online through different posts and the quantity of these posts are quite stark. The Duck system works in almost exactly the same way as the Stormguard, with warm air being trapped inside, ensuring that the temperature doesn’t drop. Considering it is one of the cheaper insulating items on the market, its quality shines through in appearance and quality, and it gives a great account of itself through months and years of use.

The Duck Indoor Window Shrink Film Insulation Kit received a great star rating of 4.2 out of 5, although it doesn’t have nearly as many reviews as its competitor, Stormguard. However, the quality of this model has been positively received across the UK and the simple tape application leaves people with a positive experience which is reflected through the list of reviews.

Tesamoll Thermo cover window insulating film

The final item on our page of product explorations is the tesamoll Thermo Cover Window Insulating Film. Again, it is installed and applied in the same way that the Duck and Stormguard products are, with 3m double sided tape applied and a hair dryer used to seal the window to make it air tight.

This product seems to be particularly adept at maintaining light within the rooms after use, which other types have been criticized for, although none of those products has made our collection. The cost of the tesamoll is again a very small investment with so much to gain.

The application doesn’t require specialist tools, or a build-up of time and space to install. The tesamoll received positive reviews, scoring 4 stars out of 5, which is a very good score considering there are over 1,300 reviewers, and this is reflected throughout the industry competitors!


Window film is a very low-cost addition to your house, which services many avenues in your property. The benefits that these installations bring to your property bridge the gap between a fully insulated house and one that is lacking in a few key areas.

The different items that we explored in our reviews are just a couple of examples that show just how easy and inexpensive it is to bolster the heat retention in your property, without compromising on space, light, cost and appearance.

Window film is a key element to maintaining the heat in your house in the winter, keeping your rooms from reaching unbearable temperatures in the summer, along removing any glare issues and harmful UV ray issues throughout the year. It’s a very simple thing to install in your house that can be done at a moments notice. If you’re struggling with the loss of heat in your property, give window film a try today!

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