Windows play a crucial role in regulating the temperature inside a house, not only in the colder months but also in summer. If the sun shines uninterrupted through the windows into the house, the heat can quickly build up and become very intense and uncomfortable, especially in peak summer times.

That’s why we’ve compiled several short- and long-term solutions to help effectively regulate indoor temperatures when outside temperatures are high.

1. Short-Term Solutions

The first two suggestions can be implemented without any major alterations to your home, meaning there are no significant costs or investments required. The downside is that these are not long-lasting fixes — they mainly deal with the symptoms, not the cause of heat buildup. Still, they offer much-needed relief during peak summer.

Keep Windows Closed During the Day

This tip might sound strange at first, as opening your windows and doors is one of the most intuitive reactions to heat.

Understandably, there is a great temptation to let in a refreshing breeze when it is hot. But the effect is short-lived. Once it is warmer outside than inside, the heat creeps through the windows into the house. Therefore, it is best to keep the windows closed during the day when temperatures are high so that the warm outside air can’t flow in.

However, you can and should still ventilate your house in summer, but only in the morning or evening when the temperatures outside are not too extreme. In these times, you should open the windows to create a good draft.

Close Your Curtains

Direct sunshine that enters through the windows can heat up your home significantly. Therefore, darkened rooms are one of the best ways to keep out the heat of the day.

Your curtains – especially those on the north-facing sides of the house – should be kept closed during the day. Light, opaque curtains are particularly suitable, as they reflect the sunlight better and heat up less than dark fabrics.

 

2. Long-Term Solutions

The above-described solutions help to lower the temperature temporarily to a tolerable level, but they are not long-lasting. As the unpleasant summer heat is a recurring issue, investing in more prolonged solutions to protect your home against high temperatures is worthwhile.

Sun Shading Systems

While curtains can help keep temperatures to some extend down inside the house, external sun protection that is attached in front of the window is far more effective.

A professional sun shading system can help create the ideal indoor climate and improve your home’s energy balance. External venetian blinds, roller shutters and window awnings ensure pleasant lighting and atmosphere in the room while reliably keeping extensive sunlight and heat out.

Large glass surfaces can be easily shaded with external venetian blinds and roller shutters for optimum heat protection in summer. Window awnings add tasteful design accents to your home’s facade and blend seamlessly with different architectural styles.

Optional insect screens can also keep out mosquitoes, wasps, and even pollen.

All these solutions are easily combined and available in a range of models, colours and designs. They work particularly well with European tilt-and-turn windows, as the inward-opening design means you won’t need to remove shading or insect protection to open your windows.

Low-Emissivity Glass

Low-E glass is an energy-efficient way to control the heat entering and leaving a house. It works by reflecting heat to its source. The glass transmits visible light but blocks heat-producing ultraviolet light and requires less artificial heating or cooling to keep the room temperature comfortable.

All ECOWINDOWS systems come standard with Low-E glass and argon filling, giving them significantly better performance compared to many conventional window types.

Solar Control Glazing

An excellent and ultimate solution to protect your home from overheating is the installation of solar control glazing to reflect incoming light.

ECOWINDOWS’ new generation of premium insulating glazing combines excellent thermal insulation and high solar energy gains with the best colour-neutral light transmission.

Premium solar thermal glass keeps your rooms brighter all year round and offers higher solar heat gain in winter for maximum transparency, and excellent energy efficiency.

On the other side, anti-sun glass offers even more sun protection in summer, especially for large glass surfaces. It reduces indoor temperature spikes while still letting in plenty of daylight.

Go Passive House

The ultimate solution for year-round comfort is building to Passive House standards.
This method ensures a controlled indoor climate using a combination of advanced building elements:

• High insulation
• Airtight building envelope
• Ventilation with heat recovery
• Thermal bridge-free construction
• High-performance double- or triple-glazed windows and energy-efficient doors

The goal is an ultra-low-energy home that provides consistent comfort and a healthy indoor environment with minimal heating or cooling. Passive Houses maintain stable temperatures of 20–22°C all year round, day and night, regardless of outdoor conditions.

Want to Learn More?

If you’d like to learn more about our sun shading systems, high-performance glazing, or Passive House windows, contact us today.