In summer, the climate depends on how strongly the building heats up over a longer period of time when exposed to strong sunlight. However, it does not always have to be an air-conditioning system that provides cooling. Less expensive measures also help to keep the heat outside.

The Energy Saving Ordinance (ENEV) devotes special attention to summer thermal insulation. No wonder, because what good is an economical boiler in winter if the bottom line is that more of the precious energy is wasted in summer through cooling?

The first thing to do is to shade your home as much as possible. Roller shutters and venetian blinds – ideally installed outside – strongly dampen the sun’s rays and prevent windows from letting heat through and thus heating up interiors. Central control via an automation system even does this automatically as soon as the sensors issue the command.

The HVAC services windows themselves can also be equipped with special glass that allows less heat radiation to pass through. This also applies to thermal insulation of the walls or the roof, because they also represent a high thermal resistance to heat from outside. This ensures that it stays cool in the building for longer.

Proper ventilation is also important

This should be done especially after sunset, when the outside temperatures have dropped significantly. It should be noted that the correct air exchange only takes place through cross ventilation: To do this, open the windows on the east and west sides of the building, for example.

If you have a garden, you can also improve the local climate by planting plants. Larger shrubs and trees not only shade very well, they also allow large amounts of water to evaporate. The evaporation cooling released in the process significantly lowers the temperatures in the surrounding area.

What good is the most beautiful awning if it remains retracted? Nothing. It is especially important in summer to keep the sun away from the large window fronts. Older awnings are usually still designed for manual operation. Here, the house owner looking for shade has to extend the awning with a powerful crank. Schellenberg has a practical solution for this: the PLUS awning drive. The battery-powered motor is simply hooked into the eyelet of the awning and attached to the house wall with a holder.

Motor helpers: cool breeze, good climate, low costs

By definition, fans are weak blowers. They are used wherever the air has to circulate. They must be installed in an indoor bathroom without windows, otherwise the humid air would condense on the walls when bathing – one litre of it can temporarily bind in the air. But even if a window is present, ventilators are advantageous: they remove the stale air more effectively, especially if there is no possibility of cross-ventilation – i.e. a second window.

If the best shading is no longer sufficient or a constant room temperature is simply medically necessary, only an air conditioning system can help. However, those interested should be aware that cooling requires more energy than heating.

Commercially available air conditioners treat themselves to around two kilowatts of electrical power. Permanently installed systems for domestic use are around 2.5 to 8 kilowatts under full load. They usually require noisy fans, which the system builder usually installs on the outside wall. In dense buildings, there could therefore be trouble with the neighbours. After all, these systems also have advantages: they not only cool, but also heat when needed. They are also easy to install. Their control reacts very quickly, which also speaks in favour of WLAN control.

Intelligent built-in fans

Sygonix has released a new model for this purpose. The IPX4 can be used either in the wall or on the ceiling. It does this by time control and can still be controlled in intensity. Several fans can thus be converted into a complete exhaust system (see also page 30). The highlight: It has a built-in humidity meter (hygrostat) that switches on the fan when a limit value is exceeded. The variable run-on time of the motor is five to 15 minutes, depending on the duty cycle.

With a requirement of only five watts at full load, the 10 cm fan is quite economical. You can buy the IPX4 from Conrad Electronic for 150 Euro.

Economical coolers

The – ideally gentle – breath of air from a fan blows away the moist, warmed air surrounding the body. The air flow creates space for water-hungry air, which withdraws more water from the body. The result: the body cools down. Since fans work quite economically, they are the most effective cooling machines in the household and in summer usually indispensable.

The Californian manufacturer Fanimation, for example, offers a wide range of chic ceiling fans, albeit not quite cheap – remote control included. For example, the Centaurus (see above) is available with six different blades that cost between 80 and 600 euros.