Insulate windows professionally

At the latest, when winter is back at the door, it is a big topic - the optimal insulation of windows. Depending on which windows you have installed and how your house meets the requirements of the Heat Insulation Ordinance, you can consider different measures for insulating the windows. Below is an overview of how you can professionally isolate your windows.

Long time the biggest energy loss

For many decades, the windows were the biggest weakness when it came to thermal insulation. Even if the facade was still so well insulated, the windows were the first major weaknesses despite the first glazing in the 1970s and 80s until the 1990s.

In window insulation, the focus is no longer just on the glazing

But the limits of feasible insulation have long since been reached in the glass and the focus is on the following elements.

  • window frame
  • Fensterlaibung

How an insulating glass window works

To understand this, it is necessary to know the mode of operation of insulating glass in the basic features. The cold outside air is constantly in motion, as is the warm air inside a building. As a result, in a single glazing always new warm air is led in front of the window and transported by the also constantly moving outside air. In principle, a one-piece glazing acts like a heat exchanger.

The heat exchange from inside to outside is stopped

If now the space between two heat-insulating glass air-tight and gas-tight filled with a noble gas, this gas layer is almost silent. As a result, almost no heat is released to the outside. With three-part thermal insulation glazing, this effect is further improved by up to 25 percent.

Insulation of window frames

Modern window frames have therefore been the next possible weak point. Therefore, window frames have now been developed, which are equipped with a corresponding thermal insulation. You recognize these window frames by the RAL quality mark.

The window reveal

With the thermal insulation of the window frames came the next weak point in the center, namely the connection between the window frame and soffit, ie between the window and the facade. This is the so-called construction connection joint. If the window and door assembly according to RAL is now carried out, you will also achieve optimal thermal insulation here.

Temporary insulation measures

But you can not always isolate heat-insulating windows so efficiently. This means that provisional transitional solutions are necessary under certain conditions, or the thermal insulation glazing according to the EnEV is gradual.

Different options

Depending on how good or bad the insulation values ​​of your windows are, there are various options open to you. With temporary insulation, special insulating films help you with single glazing.

Insulating single-pane glazing efficiently with insulating foil

These insulating films are not glued to the window, but to the window frame (always follow the manufacturer's instructions). These films already help to prevent an enormous amount of heat from escaping, since you create a space between the glass pane and the film in which the air is hardly moved. Accordingly, the heat can escape only conditionally.

According to most manufacturers, the film should be renewed after one year. However, reports from users have shown that the slides sometimes last up to 5 years and longer. Of course, the benefits must be greater than the costs.

Costs and benefits of insulating films

A square meter of single-pane glazing releases approximately 100 watts of heat when the outside temperature is zero degrees. Extrapolated to one year (and, of course, depending on the energy cost level, but rather rises than falls), the losses are around 40 euros per square meter. The price of the film, however, is only 5 euros per square meter.

Use window frames as close as possible to class 1

But with the windows alone, it is not done yet. For the window frames, the lower the classification within the frame class, the better the heat-insulating effect. For an existing or old building class "1" should be achieved, that of low-energy houses is even lower. In certain circumstances, it may be useful to temporarily swap the window frames to a more efficient class.

Isolate the construction connection joint

The last important weak point would still be the building connection joint. So far, foam rubber straps have been used for the insulation mainly, the structure of which is sponge-like. However, new sealing bands have a very dense, sometimes even compressed structure. This type of foam rubber band is much more efficient.

Tips & Tricks

Under certain circumstances, it makes sense to wait with a costly insulation of the windows and a somewhat lower insulation effect, which is correspondingly less expensive to perform. The first intelligent windows are already on the market, which are ventilated and, depending on the temperature, ventilate the windows from outside to inside or from outside to outside, etc. Insulated windows with solar technology are now also getting faster and faster to series maturity. It would therefore make sense to compare how much more energy you can save if you only temporarily isolate and wait a few years with a complex and highly efficient insulation.

Not always you just have to isolate the windows themselves. Especially if you already use thermal insulation glazing, but still do not reach satisfactory levels, you will have to look elsewhere for the cause. Until a few years ago shutters offered an effective thermal insulation effect. But the efficiency of modern thermal insulation glazings neutralizes this effect in the meantime. On the contrary, the roller shutters are inside, and also by the belt guide (with external shutters), you lose a lot of energy.

To do this you must remove the roller shutter and seal the roller shutter box accordingly. Under no circumstances may you use PU foam (construction foam). It is thermally insulating, but not airtight. This would create cold spots here, because cold air can be transported and condensation would occur, which in turn would lead to mold.

Video Board: How To Add Insulation Around Windows