Table of contents:
- You can calculate how much your new window will cost here
- Exchange desired: Modern windows have a lot of potential
- Thermal insulation - a particular strength of modern windows
- The construction of modern thermal insulation windows
- U value provides information about the quality of the insulation
- The frame materials of modern windows
- Ventilation is becoming more important in modern windows
- Expert installation is very important
Video: Modern windows top insulated best view
Modern windows have more to offer than glazing from earlier decades, and they have to: The requirements in terms of energy saving and thermal insulation have increased significantly, and besides, custom-made products are now the norm. People want bright, light-flooded living spaces. All this is possible, the windows are now high-tech products. We show you what makes modern windows.
Windows belong to every house like the walls, the roof or the door. However, a modern window must be able to do a lot, more than the other elements of a house. It connects the inside with the outside, brings light and air inside, but also has to protect against heat and cold, unwanted insights or intruders. The path from the light openings of Neolithic houses to today's double or triple-glazed windows (with their increasing requirements for energy efficiency and protection) is full of further developments and innovations. Today glass and frame have learned the perfect sealing. Current window designs bring intelligent ventilation solutions with them to prevent moisture damage.
You can calculate how much your new window will cost here
Exchange desired: Modern windows have a lot of potential
Around 17 million windows in Germany are still made of inefficient single glass. Through these leaky openings with simple glazing, valuable and expensive heating energy disappears outside. Anyone who replaces them cuts the heating costs by an average of 500 euros - every year. In addition, a good 1.9 million tons of CO 2 could be saved. Tip: KfW supports individual measures of energy renovation (such as the replacement of windows or front doors) with a loan: Energy efficient renovation (program 151).
Nowadays there is no avoiding the effective saving of energy. One reason for this is the steadily rising energy costs, but the legislator is also making more specifications than before in the context of the Energy Saving Ordinance (EnEv) when building and modernizing. That is why thermal insulation plays a key role in modern construction, and in addition to walls and roofs, window glasses and frames also play a key role.
Thermal insulation - a particular strength of modern windows
Interconnected: plastic window, with the clipped-on aluminum shell, the profile reaches a depth of 85 mm. Coated in different colors. “Aluskin” from Aluplast.
Thermal protection glass has been installed since the mid-1990s. Less than 40 percent of German windows are equipped with this. It has more than twice the insulation power of the first insulating glass that has been around since the 1970s. 3-pane thermal insulation glass is even more effective - it only loses around a tenth of the heat that escapes through single glass. Leaky old windows are constantly ventilating, new ones are tight. So the residents have to ventilate consciously to improve the indoor climate and to prevent mold. Central ventilation systems, elements integrated into the window such as window rebate ventilation or ventilation flaps take care of the exchange discreetly. It is worth installing noise protection windows on noisy streets.
The construction of modern thermal insulation windows
The window manufacturers are working on the constant improvement of their products. Modern thermal insulation windows have two or three glass panes.
The spaces between the panes are filled with an inert gas, for example argon or the even higher quality krypton. In addition, the panes on the room side are vapor-coated with metal. In this way, heat rays are reflected and can no longer escape.
Modern windows with vacuum glazing offer even better insulation. These enable even lower window thicknesses in a two-pane system with a very small space between the panes and at the same time insulation values that can keep up with triple thermal insulation glazing in the passive house. This makes the structure leaner and the weight of the windows lower. Another future technology are so-called "switchable glasses", whose panes with special micro and nanostructures can regulate light and energy flows without mechanical shading elements.
U value provides information about the quality of the insulation
Not only for windows, but generally for components, the so-called U-value or heat transfer coefficient is an indicator of the insulation properties. The value indicates how much energy flows in watts (W) per square meter (m²) and Kelvin (K) temperature difference between inside and outside - that is, how much heat is lost to the outside. The lower the U-value, the better the insulation properties.
For windows, the U-value is made up of the U-value of the glazing Ug (glazing) and the U-value of the window frame Uf (frame). Together, the value Uw (window) results for the entire window. Particularly efficient insulating panes of passive house windows can reach values of 0.5 W / W / m²K. The Energy Saving Ordinance (EnEV) 2014 stipulates a Uw value of 1.3 W / m²K in old and new buildings (1.4 W / m²K for skylights).
If you look at the U-values of past years and decades, you can see the progress made in glazing:
- Old windows with single glazing still have values of around 5 W / m²K.
- Wooden composite windows, installed until the early 1980s, have U-values of around 2.8 W / m²K.
- The U-values of the first insulating glass windows, which were installed until the 1990s, are hardly any better.
- Double-glazed windows achieve a U-value of 1.5 to 1.1 W / m²K.
- Good triple-glazed windows create a U-value of 0.9 to 0.5 W / m²K.
The g-value or total energy transmittance gives further information about the properties of windows. It relates to the sun protection effect of the pane. The total energy is added up from the solar energy that enters the room directly through the pane and the heat that glass emits to the interior after it has warmed up. The g-value takes values between 0 and 1. A g value of 0.7 indicates that 70 percent of the incident energy is transmitted. Glass with a small g-value protects better against overheating in summer. In the heating season, on the other hand, a high g-value and a low U-value are more clever.
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8 Show all Modern windows do a lot
Large format: slim and stable mullion-transom construction, adaptable to (almost) any installation situation. Aluminum shell on the outside protects wood from the weather. “FineLine” facade system from Unilux.
Simple: Makes renovating old buildings easier. Handmade according to historical models. Wooden windows with extra narrow profiles and glass rebates, treated with natural colors. "Krefeld window, " Frovin.
Supported: If the power fails, the automatic roller shutter also stops working. With emergency operation, the protective shield can still be opened and closed.
Modern: frameless wings let in more daylight. Each window is made individually. Hidden fittings make levering out difficult. Clara window.
Photo: Clara Fenster
Conversely: the windows and patio doors open outwards. If the wind blows, they close even closer. Bonus: Never clear the windowsill again! Customizable system from Velfac.
Coated: highly weather-resistant powder coating in Bauhaus-compatible colors. For a harmonious overall picture with windows, doors and facades from the "Les Couleurs Le Corbusier" color collection by Heroal.
Steered: The lower slats close completely, the upper slats can be adjusted at different angles up to 30 degrees. The effect: more daylight. Flexalum.
Adapted: The aluminum grille is installed like a glass pane: This also enables safe night-time ventilation. Up to 6 m 2 ventilation grille "424", Renson.
The frame materials of modern windows
For historical reasons, wood is certainly the classic frame material. However, plastic is by far the leading frame material for modern windows. According to industry information, the share of plastic frames in the German window market is more than half. This is followed by metal windows (especially aluminum) with a market share of around 18 percent and wooden windows with around 15 percent. Combinations are also increasingly coming onto the market, for example plastic-wood, aluminum-plastic or wood-plastic composite materials (WPC) with aluminum facing. However, the classic four are dominant:
- Plastic frame: They mostly consist of hard PVC, are light-resistant and resistant to wind and weather. There are models in all imaginable colors, lacquered or with colored aluminum shell, or also coated with colored acrylic glass. One disadvantage is that plastic frames get dirty easily; on the other hand, they are usually easy to clean. They are often made up of several chambers with layers of air and are therefore somewhat larger than frames made of other materials. The multi-chamber systems increase the insulation performance.
- Aluminum frame: They can be anodized, i.e. covered with metal, or they are given a colored powder coating. With such weatherproof coatings, aluminum frames can withstand extreme loads. In addition, they have very good static properties, which is why large window areas can be manufactured with very thin frames. Other advantages: aluminum frames are easy to clean and very durable. One disadvantage is that metal is a good heat conductor, which means that aluminum frames generally have poor insulation properties. However, the industry has recently been able to improve the values here through better designs.
- Wooden frame: They are made from pine, oak and spruce, among others. The advantages: As a renewable raw material, wood is environmentally friendly, it naturally has good thermal insulation properties, and old wooden frames often do not have to be recycled or disposed of. One disadvantage is that wooden frames have to be painted with paint or glaze on a regular basis, even if modern manufacturing and treatment processes extend the painting intervals. Chemical, thermal or mechanical processes are used to improve the properties of the wood so that it becomes more weather-resistant and better tolerates temperature fluctuations.
- Wood-aluminum windows: This combination of materials combines the advantages of wood and aluminum and is therefore becoming increasingly important. On the inside, the wood creates a good living atmosphere, on the outside, aluminum cladding improves weather protection. This is how wood-aluminum windows look good even after many years.
Ventilation is becoming more important in modern windows
Ventilated: Air exchange is possible even with the sash closed: with a window vent. Different levels of action. “Ventra” from Hautau.
Leaky old windows almost always aired. Modern windows keep tight, which means that residents have to deliberately ventilate to improve the indoor climate and prevent mold. In this case, central ventilation systems (or elements integrated in the window such as window rebate ventilation and ventilation flaps) take over the air exchange. In the case of subsequent automation, you have to plan the power supply.
Expert installation is very important
As described, modern windows have very good thermal protection properties. But these can only have an effect if the windows are also installed professionally. This means, for example, that they have to be connected to the walls without thermal bridges. At the same time, the joint sealing must be carried out professionally to ensure windproofness and protection against moisture. In addition, shutters or blinds should be included in the window planning. They can further reduce heat losses and protect them from the sun in summer.