Berlin  – With high summer approaching in the northern hemisphere and temperatures rising, many people will be seeking refuge in the cool shade of their own four walls. But even inside a building temperatures can quickly reach 30 degrees Celsius or more, putting a strain on the heart and making it difficult to sleep.

To stop that happening the best thing is to prevent temperatures in your home from getting too warm in the first place. That’s because once a room has become very hot it is difficult to cool it down again.

“The first thing you need to ensure cool rooms in the summer time is good insulation,” says Uta Maria Schmidt, a home construction advisor at Germany’s consumer protection office in Mainz. If a building is correctly insulated the windows become the only factor that can allow temperatures to rise inside.

Buying an air conditioner for your home may seem like a sensible solution to uncomfortably warm nights, but Schmidt warns that tests by the consumer safety watchdog, Stiftung Warentest, showed that they use a lot of power and are also very loud.

“Rooms with sky lights are prone to becoming very hot,” explains Gerhard Rommel, an expert on blinds and sun screens in Bonn.

In lower floors, a common misconception is that only south facing rooms can get too hot. But in many cases east and west facing rooms can also become uncomfortably warm. “The rooms’ lower level means that more low-angled sun rays can get in.”

The best heat-protection method is to provide your windows with some exterior shading such as that given by a leafy tree or an extended roof. “Exterior roller blinds can also be installed retrospectively,” says Rommel.

Roller blinds are housed in a box that is easy to build into a window’s alcove. However, you will lose some of the window’s surface. Exterior shutters can also be installed retrospectively on a house or apartment.

Marquees on the other hand have significant disadvantages. They only protect against the sun’s rays but not against warm air. Windy conditions also mean you cannot use a marquee. Awnings for their part are very expensive.

Because any sun protection system attached to a house will change its character, you will need permission from your house owner if you are a tenant.

Blinds, screens, curtains or any other type of sun protection placed on the inside are less effective but can prove useful.

“They should not be attached too close to the window to prevent a pocket of warm air forming,” advises Rommel. You should also make sure that the window remains free and easy to open.

Roller blinds and louvered blinds should be light coloured or coated with an alloy to reflect warmth and sunrays. Tinted glass or coated window panes will also partially filter heat. The same applies to red-tinted reflective gels that can be stuck to the inside of a window pane.

“But with this method, you must also remember that during winter months the gel will continue to reflect light and warmth,” says Werner Eicke-Hennig from Germany’s Darmstadt-based Institut Wohnen und Umwelt, a organisation that researches improvements in housing for socially disadvantaged groups.

Sunlight is not the only source of heat in a house during the daytime. Airing a room can also allow heat to enter a building, even when blinds are in place. “The best thing is to only ventilate a room during the late evening or very early in the morning,” advises Eicke-Henning.

He also advises using a fan or ventilator but do make sure it is as quiet as possible. Also make sure any ventilator is not placed in a position where it blows air directly onto a sleeping person, otherwise it might cause a summer cold or discomfort.

Moist cloths hung in front of a window can also ease the affects of strong heat. Turning off any unnecessary sources of heat such as a light or other electrical appliance will also help reduce warmth.

Consumer protection officer Schmidt also recommends doing some light endurance exercise or taking a lukewarm shower. They help to open the body’s pores and prevent excessive build up of body heat.

“Don’t dry yourself too much as evaporating water can help your body cool down,” says Schmidt.

You can also enjoy a cool summer’s night by getting into nightwear that has spent some time in your ice box and make sure you have plenty of fluids to drink by placing a bottle of mineral water beside your bed. (dpa)