How to darken windows with solar films

Summer is here and with it the heat waves.

Window solar film anti UV

Protecting yourself from the heat in the summer is quite a challenge for those who are not equipped with an air conditioner but still want to avoid roasting (or perhaps it would be better to say boiling) in their homes.

The air conditioner is certainly a wonderful invention but it is also true that it affects energy consumption and increases the cost of the bill.

In another article we have already talked about how to protect ourselves from the heat by closing shutters and windows, but on this occasion we would like to talk about how to limit as much as possible the solar radiation without giving up the light that the sun gives.

This is possible thanks to the solar films that are able to filter most of the solar energy while maintaining intact the visibility to the outside.


As everyone knows, the windows are a multiplier of heat when they are hit directly by sunlight and this we will have experienced all leaving the car parked in the sun, in summer.

Home window panes, being double glazed, partly reduce heat transmission but they certainly remain the weak point of those whose homes are exposed to the sun and who do not have air conditioning.

The only way to ensure that the sun's rays do not directly hit the glass is to interpose a physical barrier between the sun and the windows.

This means, in most cases, installing awnings on the outside.

However, awnings have many disadvantages: they are expensive, they tend to get dirty, they are difficult to install and manage, and above all it is impossible to put them on all the windows of a facade because the aesthetic effect could be very impacting.

Another solution consists of blinds to be mounted internally that must be light in color, preferably white, to better reflect the sun's rays.

This solution, however, has the disadvantage that part of the heat due to radiation will tend to spread in the interior.

One thing is certain: the larger the glass surface, the greater the risk of the house becoming an oven in case of direct radiation.

Window tinting solar films are, if you will, a middle ground between external and internal blinds.

One way solar films are relatively easy to install and are therefore within the reach of all DIY enthusiasts.

These types of solar window films are applied by contact, they are not adhesive. When properly mounted they adhere perfectly to the glass and do not form bubbles. The advantage over adhesive films is that they are repositionable, which also allows you to fix mistakes.

What is important to know is that these films are able to shield up to 92% of solar energy and for this reason they are also rightly called anti-heat films.

The darker and more mirrored the films are, the more they will be able to reflect solar radiation.

How to apply sun protection films on glass

These films are applied to the outside of the glass by contact.

The tools needed to get a good job are not many but they are indispensable:

  • water sprayer
  • spatula to avoid the formation of bubbles
  • cutter to cut the film along the edge

Before applying the solar film it is necessary to clean the glass very well and then wet it with the sprayer.

At this point you spread the film and after wetting it again with the sprayer you start to remove the bubbles and water starting from the central part and proceeding outward.

All the steps are well described in this video.

These solar films contain a UV filter that after application will prevent the rays that filter through the glass from continuing to discolor the furnishings inside the house, such as carpets, furniture, and pictures.

From the outside, these anti UV films will appear with a beautiful mirror effect like the one you may have noticed on the windows of skyscrapers that, precisely because of their very large glass surface, need tinted glass to avoid becoming colossal heat accumulators.

From the inside, visibility to the outside will be only slightly reduced.


In addition to shielding the glass from the sun, these films also perform a useful and not secondary function of obscuring prying eyes because from the outside you will not be able to see inside and this is to the benefit of privacy.

The advantages of solar anti UV films

Summarizing the advantages of these films we could list them as follows:

  • with a thickness of less than a millimeter, these very thin polyether films save us the cost and space of external and internal awnings
  • the anti-heat films reduce the temperature inside the house and this reduces the use of air conditioning with a considerable energy saving
  • they perform their function for many years, if installed correctly, and if we ever get tired of them we can easily remove them from the windows
  • no need to ask for permits or authorizations as could happen for the installation of physical structures such as awnings that significantly change the aesthetics of the building
  • mirror effect sun protection films are also very good from the point of view of privacy

Last but not least: these films, in addition to shielding from the sun, have a potential and very useful function in case of accidental glass breakage, preventing the splinters from scattering, at least on the part to which the film is anchored.

In short, with a job within the reach of do-it-yourselfers, you can obtain countless advantages at a relatively low cost compared to other systems and, above all, you will still be able to enjoy the sunlight without necessarily having to barricade yourself in your home by closing shutters and windows to protect yourself from the heat.

DIY Editor
Do-it-yourself enthusiast. I started with the renovation of my flat and then I changhed this passion into my job.