Solar shading

How sun screens keep your home as much as 10 °C cooler

Summer is fabulous as long as you can find a place to cool down too. You can seek out the sultry summer sun and then enjoy a more refreshing temperature. That is the ideal scenario. But, if outdoor temperatures are searing and you cannot cool down indoors, it might not be quite so pleasant. An expensive, energy-hungry air conditioning unit will cool your home but offers no further benefits. A screen or sun canopy, however, does. This solution will keep your home up to 10 °C cooler without any effort on your part or any damage to the environment. So, how does it work? We will explain.
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Sun screens: what exactly are they?

A sun screen is an outdoor device that is installed on the outside of your window. It comprises a taut fabric which filters sunlight while maintaining the view outside. It prevents solar heat from coming indoors, so the interior remains nice and cool but you don’t have to sit in a dark, closed-off space. Screens can be built into the building’s façade, but you can also secure them directly to the window. This provides a range of options for renovations.

The impact of the sun on indoor temperatures

Sun screens prevent overheating

One option that can be fitted quickly to prevent overheating in your home is indoor sun screens or air conditioning. Initially, it may seem as if curtains or internal slats are keeping the heat at bay but, in reality, the effect is only temporary. The radiation has already come through the glass so it takes a great deal of energy to cool the house using air conditioning. 

Outdoor sun screens are, therefore, much more efficient: the glass on the outside offers protection against the sun. If you choose automated sun screens which are triggered whenever they are needed (or even before they are needed), you can effectively stop the heat coming in. 

Screens are fitted directly in front of the window and offer immediately relief. They comprise a specially designed fabric, usually made form polyester or fibreglass, and there is a range of different transparencies. The darker the screen, the better you retain your outdoor view.

The science behind Harol’s efficient sun screens

Light reflection

Sun screens are highly reflective and reflect a high degree of the incoming sunlight. This reduces the direct exposure to the sun and lessens the heat transfer.

Light absorption and transmission

Harol screens also absorb some of the sunlight that gets through. The heat that comes with it can then escape outdoors thanks to the fabric’s open structure. The window thus absorbs less heat, allowing indoors to stay cooler. 

Air circulation

Outdoor sun screens ensure that air can circulate between the window and the screen. This air circulation helps dispose of heat and contributes towards keeping the window’s surface cooler. This circulation can also help to reduce condensation on the window.

Shade and the reduction of light penetration

The screen also functions as a type of shade screen for the window, blocking out direct sunlight. This reduces the degree of heat that penetrates through the glass. The combination of light reflection, light absorption and shade creation helps to maintain a cool climate within the home. The exact impact can vary depending on factors such as the intensity of sunlight, the orientation of the window and the properties of the screen material used.

The most important benefits of our screens


Harol screens are energy-efficient solutions for keeping the sun out. Particularly our solutions which work entirely on solar energy, as they are extremely economical. 

View outdoors

You maintain your view outdoors with screens and don’t end up with a dark room. The darker the fabric, in fact, the better your view.


Our quality screens are able to withstand high winds, up to Beaufort scale 6.


Our screens are also mosquito-proof, stopping flies and other insects in their tracks.

Choice of fabrics

Our broad range of low-maintenance screen fabrics means there is something for everyone, in terms of transparency but also colours.

Sleek, taut fabrics

Thanks to the anti-wear and tear technology applied to the fabric, and the ingenious ZIP system, the fabrics stay taut for many years.


An automated system activates the sun screens at the optimum moment, resulting in a pleasant indoor climate while retaining natural daylight. The smart management of solar heat allows CO2 emissions to be reduced. In the summer, there is little or no need for cooling with an energy-hungry air conditioning unit. In the winter, you gain optimum benefit from the passive solar heat, reducing your need for heating. Did you know, for example, that you can save as much as 80% on your energy bill if you reduce your need for artificial light? 

Sun screens also have a positive impact on the energy performance of your home. This assessment not only incorporates the degree of insulation but also the sun accessibility factor, i.e. what is the orientation and how is the shade created on the windows? Are there screens, blinds or other forms of sun-reflecting screens available? These issues must all be taken into account when determining the EPC score.

It is clear that screens offer a range of benefits in your home. They principally provide comfort and keep your home cool when the heat is building outdoors. Does that sound like music to your ears? The distributor in your area will be happy to talk to you about the options. 

Want to discover solutions that will cool your home naturally?
Find out more about the options with your local distributor.
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