Closing sockets reduces heating costs

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We all have our own sensitivity to unpleasant drafts, but as a rule we can assume that we perceive the disturbing draft when the air speed is more than 0.2 meters per second, which is about four times slower than a walking one Person. In winter it doesn't take much for a corner in the apartment or office to be perceived as uncomfortable - the cooler the draft is the draft becomes all the more uncomfortable felt, even if it should only be very weak. It is worthwhile to detect and reduce drafts in a heated building, because draft increases energy consumption in an indirect way: The cool draft prompts the residents to turn up the heating to compensate for the feeling of cold.


Three easy ways to spot draft

With a light ribbon

This process consists in making a kind of fishing rod made of a stick to which a very, very light "thread" is attached: for example a thread of wool, a silk ribbon, a piece of magnetic tape (from an old audio cassette) or a strip of multilayered tape Toilet paper from which a layer has been torn off, or something similarly light.

Hold the stick in front of you and move very slowly in the rooms so as not to interrupt the draft or to cause drafts yourself. Walk along the walls and hold the stick in the corners of the room, in front of the windows, in front of sockets and roller shutter boxes ...

With soap bubbles

The colorful tubes for making Soap bubbles can be bought at the kiosk or in stores that have a toy department. Soap bubbles are very effective in recognizing large air movements (e.g. running up stairs). But be careful, they can leave a sticky residue if they burst.

With incense sticks

There Incense sticks Burn very slowly, they create a visible thread of smoke that can be used to indicate where there is draft. Hold the incense stick at arm's length and slowly move along the windows and walls. Move back and forth carefully so as not to affect the draft. This method is also suitable for checking the functionality of the ventilation grilles for the exhaust air from the kitchen, bathroom and toilet. Is the apartment with Fire alarms equipped, be carefully, in order to no alarm is triggered!

Unfortunately, the reason incense sticks give off visible smoke is that they are so many Fine particles release. Aside from determining where the draft is coming from, for the sake of your health it is better not to let it burn down around the house.

Scientific instruments

Portable anemometer

This is also one of the professional instruments Anemometer (in German anemometer), which was specially developed for measuring low air velocities inside buildings. They can be used to record and characterize air flows or to regulate the air flow rate of ventilation systems.

Recording a Entrance door in winter from the point of view of a thermal imaging camera. The cold air that penetrates under the door cools the floor tiles down considerably.

Thermal camera

In winter you can also do one Thermal camera to make the penetration of cold air visible, because this cools the material around the cracks or the leaks of doors and windows.

But even without technical aids, you can detect a draft: Sometimes there are spider webs in places where the air currents are strongest: Spiders settle there because the air movements drive the flies and mosquitoes directly into the trap ...


formation ofPassage and remedial means

  • Cold airflowwho through leaky windows penetrates.
    Remedy: Attach self-adhesive window seals (find out more at a good hardware store, as there are different brands with different lifespans). Replace the Windows> Glazing and Windows.
  • Cold airflow, because the Insufficient wall insulation is.
    Remedy:Insulate the facade from the outside (preferred solution) or from the inside.
  • Cold air penetrates Insufficiently insulated roller shutter boxes a.
    Remedy: The air can either penetrate unhindered because there is a fault in the closing device of the roller shutter box (if it is installed inside the building) or through the opening or closing mechanism of the belt or crank (if the box is installed outside). Insulating and sealing a roller shutter box can significantly improve the comfort of an apartment. However, this work should rather be carried out by specialists.
  • Cold airflow comes from the electrical sockets.
    Remedy: Air flows out of the socket! This is not all that unusual: the ducts that lead the electrical lines sometimes also bring cold air into the rooms from outside. Have a specialist dismantle the socket cover and seal the fuse box. This work should really only be carried out by electricians (before carrying out any work it is essential to disconnect the power supply from the socket in the fuse box!)
  • Draft comes from the switched off extractor hood.
    Remedy:Extractor hoods have an exhaust air duct that leads the sucked in air outside. Check whether the duct has a flap that prevents wind from entering the cooker hood or the kitchen.
  • Draft due to strong automatic room ventilation.
    Remedy: If the problem occurs in a rented apartment, check with the neighbors if they have the same problem and then contact the administration or the landlord. Plugging the ventilation grilles is not a good solution: the apartment is no longer properly ventilated and the ventilation of the other apartments may even be disturbed.
  • Draft through a very hot radiator which is attached to a cold outside wall (or under cold windows) in a room with insufficient insulation.
    Remedy: The radiator actually does its job perfectly. Due to its warmth, it creates a rotating movement of air in the room. But the warmer the radiator, the stronger the draft. If the temperature of the radiator is lowered by closing the valve a little, the air circulation is reduced, but the heat may then no longer be sufficient. Insulating the building and replacing the windows can solve the problem, as you can then heat with less warm radiators.
  • Airflow coming down an open stairwell between two floors arises.
    Remedy: As a rule, the warm air rises from the lower room to the upper floor by collecting on the ceiling and then pulling it through the open staircase to the upper floor. Putting a heavy fabric curtain at the bottom of the stairs can help limit drafts. Pay particular attention to a good barrier effect of the curtain at the top of the ceiling.
  • Passing through a conventional fireplace with open fireplace.
    Remedy: When the fire is burning, a fireplace with an open hearth creates a strong draft, because at the same time as the smoke is being removed through the chimney, the fire sucks in warm air from the room, which is exchanged for cold air (which enters the building through leaks) becomes. But even when there is no fire, such a fireplace often creates drafts, even when the draft hatch is closed. Upgrading a fireplace can be very beneficial, both in terms of home comfort and energy savings.


3 types of buildings, 3 types of draft

Old building: Defects in the window seal are part of the building ventilation

In an old building that has not been renovated, some of the air is renewed through leaks in the building. In most cases there are no ventilation grilles: "Fresh" air enters through leaky windows and the door that does not close tightly. Used air is directed outside through the extractor hood in the kitchen or suction openings in the bathroom and toilet. However, over time and as the building ages, the windows let more air through, and cold air also enters through cracks in the walls or along the pipes. Air can even flow out of the electrical sockets as well as the openings in the ceiling from which the electrical cables for the lamps come.

In an old, non-renovated apartment of around 100 square meters, the sum of all cold air inlets can correspond to an air exchange that takes place through a small, constantly open roof hatch the size of an A4 page - which by far exceeds the normal ventilation requirement. It is generally assumed that the air in a living space moves at a rate of 30 m3 has to be renewed per hour and person - which corresponds to a flow of air that gently enters through a hole 5 centimeters in diameter.


Modern building (well thought out and high quality built): walls and windows close tightly and the air exchange is controlled by an automatic ventilation system

A well-built modern building (or a well-refurbished old building) not only has very good thermal insulation, but also is sealed against air inlet. Therefore, the air renewal is usually carried out by a ventilation system, which introduces fresh air through grille inlets into the bedrooms and living rooms and sucks the stale air through other grille openings in the kitchen, bathroom and toilet - i.e. from the rooms in which most of the pollutants and the highest levels of humidity arise. If one speaks of "comfort ventilation", a heat exchanger is also included, which makes it possible to transfer the heat from the exhaust air to the cold fresh air supplied from the outside. But drafts can also occur in such a building, for example if the ventilation system supplies too much air, or if the residents intentionally close the ventilation grilles (or unintentionally adjust them with furniture) and thus disrupt the circulation of air between the rooms. But if the air circulation in the apartment is not working properly, the airflow is concentrated in certain places and creates an unpleasant draft ...


Partially renovated old building without comfort ventilation

Unfortunately, this solution is found very often: The old building was provided with new, well-insulating and tight windows, but no new air inlets were installed. If the exhaust grilles in the kitchen, bathroom and toilet still suck in a lot of air, drafts can occur under the entrance door or through cracks. Ventilation slots on the new windows should be considered for the benefit of the health of the residents and of course also to avoid problems caused by moisture, which can promote mold on the cold walls. There are automatic, hygrostatically controlled ventilation controllers (without batteries, without electricity) that open or close according to the room humidity.

However, only insulating the fa├žade can solve the problem of cold walls and moisture from condensation.



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