Windows: "history of struggle"
The transparency of the outer shells of buildings, which we previously wrote about, in particular in the article "Post-privacy and uber-transparency. Trends That Changed Modern Architecture' not only opened new possibilities and allowed a person to enjoy the scenery while staying in a protected space, but also created a number of user problems, which, however, are successfully solved thanks to modern technologies.
"The history of architecture is the history of the struggle for the window," declared in 1929 the founder of modernism, Charles-Edouard Jeanneret-Grey, better known to the world as Le Corbusier. Strapping buildings with ribbon windows, Corbusier was guided by the desire to let the maximum amount of light into the house throughout the daylight hours.
An example of the use of Schüco AB ZDS (Aluminum Blind ZIP Design Screen) — an external textile system of wind-resistant roller blinds. Image source: schueco.com
Over the millennia, the window evolved from a tiny opening through which precious heat escaped to panoramic glazing systems with five-meter remote-controlled sliders. Modern technologies of external sun protection allow people to feel like magicians: even with the maximum adjustable shading from the outside, the windows remain transparent from the inside, which allows maintaining the connection between the internal space and the surrounding world. Protecting yourself from the sun, you don't have to sacrifice a beautiful view. This possibility is especially important when it comes to panoramic windows on high floors. The view outside the window is important, developers and architects are sure.
Glazing is a contemporary of our era. At the end of the first century, Roman glassblowers discovered that adding manganese oxide to a molten mixture of sand, lime, and soda allowed them to create transparent glass. Sizes, parameters of the frame, accessories and sun protection - different countries have their own options for designing window openings, which also depend on the climate and cultural traditions.
For centuries, windows have been a symbol of luxury. In England in 1696 they even introduced a tax on windows. Houses that had more than 10 windows (and later - 7) were taxed. This law hit the health of the nation hard—for the next 200 years, residents of poor tenement slums, where windows were boarded up and bricked up for reasons of economy, suffered from a lack of insolation and ventilation, and died by the hundreds from typhus, smallpox, cholera, and other diseases. The tax was abolished only in 1851. But this story may well explain the fact that in the New World (and not only there) glass skyscrapers still remain a symbol of prestige and prosperity.
If in ancient times the window was the most vulnerable element of the building's thermal envelope, today, when modern windows compete with insulated walls for their protective qualities, they are the main tool for managing the internal microclimate.
How to define comfort?
A comfortable indoor microclimate is a subjective concept, since each person has an individual mode of activity and thermoregulation of the body. Physical characteristics such as height, weight, age are important. The difference in sensations can be significant: someone is hot at +18°, someone is cold at +26°. Air flows and the temperature difference between the air and the surrounding surfaces (external walls, ceiling, floor or window) play a role - it should not be more than 4,2 degrees. On average, a comfortable temperature for people is from 22° C to 27° C and air humidity from 40% to 60%.
Schüco AB ZDS solar protection system integrated into Schüco facade systems. Image source: schueco.com
In Ukraine, the microclimate in residential, educational and working spaces is regulated by a series of state standards, in particular DBN B.2.5-67:2013 "Heating, ventilation and air conditioning" and DSTU B EN 15251:2011 for various types of premises in the range from 18 to 27 degrees.
Sanitary and building regulations are not constant and can be edited depending on current state policy and economic conditions. Last winter, taking into account the Russian attacks on Ukrainian infrastructure and the shortage of energy resources, the Cabinet of Ministers of Ukraine lowered the minimum temperature standards in residential premises from 18 to 16 degrees Celsius.
The natural desire to create an optimal thermal environment in houses according to the individual needs of residents contributes to the demand for autonomous heating systems and modernization of buildings with the aim of warming them.
In the article "A higher level of freedom for an architect. Schüco: those who know how" we have already described the history of the company - a market leader in the field of development and production of system solutions for windows, doors, facades, security technologies, sliding and sun protection systems. Now let's focus on practical ways to create an optimal microclimate for home and office.
Oleksiy Sverchkov, commercial director of Schüco Ukraine
Oleksiy Sverchkov, commercial director of Schüco Ukraine: "It is important to understand that achieving energy savings is possible only if all the component parts of the facades meet high requirements. The use of a highly insulated aluminum system without a suitable double-glazed unit or saving on the elements of connecting the translucent structure to the building brings all efforts to naught. In the early 2000s, Schüco specialists foresaw the energy-saving trend and began a huge effort to develop new systems. Moreover, this is not the modernization of the existing ones, but the creation of completely new platforms.
Achieving energy savings is possible only if all the component parts of the facades meet high requirements
The new systems had to not only meet the highest requirements for insulation, but also make it possible to install double-glazed windows of an unprecedented thickness of 50 mm and above, weighing from 500 kg. Today, you won't surprise anyone with energy-efficient double-glazed windows of a panoramic format with an area of more than 10 square meters. m and weighing more than 1 ton. At the same time, their thickness reaches 70 mm.
We have come a long way to implement such projects, it is not only the development and launch of a series of new products and their testing, but also thousands of implemented objects in all corners of the globe. This invaluable experience enables us to look to the future with confidence. We perform calculations using specialized software, study heat flows, temperatures on the surface of various materials under different regimes (temperature, humidity), the flow of isotherms, the position of the dew point, and much more. These calculations provide information for making very important decisions, on which the performance of the entire structure depends in the future."
The right windows for a passive house
The pursuit of energy efficiency motivates customers and designers to turn to progressive concepts, in particular the passive house concept, which is the leading construction standard in Europe.
The design of a passive house is aimed at minimizing and ideally reducing to zero the use of energy-consuming active heating and cooling systems. Compared to the average new building, passive houses consume 75% less energy. They are sealed, and in this design the window itself is the most effective tool. With the help of the window, the light level, air quality, temperature and noise are controlled. At the same time, the windows must meet the general requirements of the passive standard.
Schueco FWS-35‑PD panoramic facade, officially certified by the Passivhaus Institute. Image source: schueco.com
The growing interest in the construction of passive buildings is noted in various countries, but Germany is the unequivocal leader in the field of standardization and certification. Since 1996, the Passivhaus Institute in Darmstadt (Germany) has developed design strategies for different types of climates, as well as "passive house comfort criteria" for different climate zones. According to strict regulations introduced in June 2022, doors and windows must have a heat transfer coefficient of no more than 0,8 W/m2ˣС.
Schüco has in its range a complete set of Passivhaus products, including hinged element facades, windows and doors, which are available even for Ukrainian customers. Their use is possible not only in new construction. Replacing old windows with a certified Passivhaus product in houses of the 60s and 80s will help reduce energy consumption by more than 20%.
Oleksiy Sverchkov: "Unfortunately, today, among the requirements of Ukrainian customers, compliance with passive house standards does not happen so often. There are several reasons and many explanations for this. First of all, there is a lack of visibility of this definition and a lack of understanding of why it is needed. Everyone understands that it is necessary to build energy efficiently, but many of our processes have not yet been formalized and have not been built into a single policy. It is very important to popularize this issue, as well as to encourage developers to meet these standards. The situation will definitely change.
With the help of the window, the level of illumination, air quality, temperature and noise are controlled. Windows must meet the requirements of the passive standard
Here is just one example: even 15 years ago, the use of double-glazed windows was a luxury that only a few could afford. Today, single-chamber glazing for enclosing structures is simply a taboo. Moreover, in all regions of Ukraine, regardless of the climate. On the other hand, energy efficiency standards are getting stronger every year and will eventually be harmonized with European standards. This gives hope that when choosing certain materials for construction, preference will be given to those that meet the criteria of a passive house. Today, the customer is satisfied with what is regulated by DBN. It is also important that all components of the future building meet passive house standards, and this is already a special design approach.
Even at the stage of the sketch project, fundamental criteria are established: the location of the premises according to the cardinal directions, lighting, the influence of natural factors (rain, wind, sun, etc.). In private construction, the situation is somewhat different, where the customer is interested in indicators and is ready to go for higher standards for his own home. He does not consider it an unnecessary overpayment."
Smart glass as household magic
If we have already mentioned Le Corbusier, it is worth noting that the apologist of tape glazing systems was not a prisoner of the idea of radical maximization of insolation, but primarily focused on common sense and climatic features of the area, designing spaces that are illuminated, but at the same time protected from overheating.
Examples of the use of SageGlass® dynamically tinted glass in Schüco window, door and facade systems. Image source: schueco.com
Bringing back from half-forgotten the idea of solar panels on the facades, the architect made the multi-colored brise-soleil a feature of the Unité d'habitation residential buildings in Marseille and Berlin. The almost blank brick facade of the Indian Museum in Ahmadabad is in keeping with India's hot climate. The insolation of the building is solved here due to the first floor, raised on pylons, and an internal patio. Today, the museum could look a bit different, maybe it would be more open. In the same way that pharmacists improve sun protection products for the skin, technological engineers improve the quality of window systems, endowing them with new characteristics, including protective ones.
In recent years, the climate of Ukraine has been changing quite rapidly from moderately continental to sharply continental. The difference between summer highs and winter lows is 70-80 degrees. The number of days with extremely high temperatures, so-called "heat waves", when the daytime air temperature exceeds 30-35 ° C, has increased significantly. In the south and east of the country, the number of hot days without rain can reach 70 in a row! A warm summer does not exclude abnormal frosts in winter. In such conditions, the topic of climate architecture should be at the top of discussions.
Examples of the use of SageGlass® dynamically tinted glass in Schüco window, door and facade systems. Image source: schueco.com
In summer, there is a need to shade a large area of glazing and ventilate. In a word, competent management of thermal energy is necessary
Increasingly, the projects of Ukrainian architects include winter gardens, which are not only an extension of the living space, but also act as a heat accumulator on sunny winter days. But in the summer there is a need to shade a large area of glazing and ventilate. In a word, competent management of thermal energy is necessary.
Oleksiy Sverchkov: "Energy efficiency is not only a story about saving heat. It is important to create comfortable conditions for living or working even in the hot season. It has long been estimated that cooling a room to a comfortable level in the heat is three times more expensive than heating it in the winter. Although double-glazed windows are not our specialty, here we still offer our customers comprehensive solutions. We are talking about the so-called smart glass, or double-glazed windows with variable transparency. This is a cooperation with the famous glass manufacturer Saint-Gobain. The product is called SageGlass® and is a dynamically tinted glass for Schüco windows and facades. Glass changes its color when a small electric charge is applied by activating electrochemical processes.
The degree of light transmission of electrochromic glass can be adjusted in the range from 1% to 60%. Image source: schueco.com
Three different toning zones can be created with the LightZone® function. For example, in the upper part of the double-glazed window in high sunlight, it is darker, and in the middle and below it is more transparent for visual contact with the environment. A gradual toning transition is also possible using the Harmony™ function. Features can be controlled automatically, at the touch of a button, or through the SageGlass® mobile app.
Four colors of double-glazed windows are available as standard, other colors are available upon request. This is an excellent solution for vertical structures, and above all for roof lights, for winter gardens.
An example of the use of the SageGlass® solar protection system: the administration building of HeKa Herzog GmbH in Graben-Neudorf, Germany. Image source: schueco.com
The costs of cooling the premises will lead us to the point where external solar protection systems will become simply irreplaceable
In general, sun protection is the most important parameter for a person's comfortable stay in a building. External sun protection is the most effective means against overheating. But, unfortunately, these are additional costs during the arrangement of the facade of the building. Customers are reluctant to go for it, since these costs are added to the cost of construction. But I'm sure that over time, the installation of external units of air conditioners on the facades of buildings will be prohibited, and the costs of cooling the premises will lead us to the point where external solar protection systems will simply become irreplaceable. And if it is fixed at the level of building regulations, then we will feel how much more comfortable and convenient our buildings have become."
An example of using the VentoTherm Twist ventilation system in school spaces. Image source: schueco.com
Ventilation and elegance
To let light in, to protect from light. What else? Of course, the window is a source of natural fresh air. 20 years ago, when Ukrainians began to use almost hermetic double-glazed windows en masse, they faced such unpleasant problems as suffocation, condensation and mold. The old wooden windows provided air exchange in the premises so successfully that many residents of "Khrushchev" even closed the ventilation grilles of the house, not seeing any sense in them. Well, they had to be opened.
Weak fittings of plastic economy windows were expensive and not very reliable - they quickly failed. "Deaf" double-glazed windows were popular. However, the user experience quickly showed the harmfulness of such savings not only for people's health, but also for the health of buildings.
Schüco has super-technological solutions for ventilation, in particular for projects of particularly sensitive spaces - medical clinics, schools, as well as for customers demanding the aesthetics of an architectural object.
The concept of decentralized ventilation makes it possible to improve the air quality in the room many times and reduce costs if the room is not in use
Oleksiy Sverchkov: "We need to clearly divide ventilation into natural - with the help of elements that open, and forced ventilation, when different equipment is used for air flow. Schüco can offer a large number of solutions for both the first and the second case. If we start with natural ventilation, I would like to point out that the topic of elements that open is one of the central ones for the Schüco company. All of our facade systems have the possibility of incorporating many options of sashes, moreover, for different types of opening, dimensions, types of control, and at the same time meet the highest design requirements.
We pay attention not only to safety, comfort of management, but also to what the opening sash looks like from the facade. Do not the intersections of the profiles stand out too much, creating a dissonance with the facade? Our latest developments offer opening elements completely hidden in the plane of the facade. A demanding designer will ask: what about the inside? We will answer that our windows perfectly complement the design of the room. This is, of course, thanks to completely concealed hardware and exquisite handles that have received the most prestigious design awards, including the Red Dot Award.
But that's not all: we went further and thought about how attractive the end of our window looks in the open position. I want to tell you, it looks as wonderful as, for example, the space under the hood of a prestigious car. All mechanisms are hidden, technological nodes are covered with overlays made of quality materials. And to top it all off are Co-Brand Clips, a joint logo of the window manufacturer (or customer) with Schüco on a special metal plate. This is just an example of our love for details.
An example of using the VentoTherm Twist ventilation system in school spaces. Image source: schueco.com
Of course, in recent years we have been actively developing the topic of mechatronic opening control. All our systems can be motorized and controlled both by computer and through special mobile applications. As in the case of mechanical accessories, all electrical components are hidden in the profiles, and the window does not differ from the usual one.
By the way, these solutions are often used in hospitals and schools, where it is necessary to provide ventilation without human intervention (for example, students or patients). Usually, to save space in a classroom or in a hospital ward, opening transoms are installed high up in a hard-to-reach place, so remote opening at a scheduled time is an ideal solution in such a case. Natural opening is the easiest option to provide the room with fresh air in a short period of time. But only when there is really fresh air outside the window, and through the open window you cannot hear the tremendous noise of the street. For such cases, we have a whole range of solutions — various forced ventilation devices, equipped with filters and air recovery systems. These can be small panels, those that are built into the window, and more serious devices that are placed in the parapet space and are fully responsible for a comfortable climate in the room. This is the concept of decentralized ventilation, which makes it possible to improve the air quality in the room many times and reduce costs if the room is not in use (if a person is on vacation, on a business trip, etc.).
One of the novelties of this direction is the Schüco VentoTherm Twist ventilation unit. The principle of its operation is as follows: with the help of a pair of fans, a continuous supply of fresh air is ensured in the room with the simultaneous removal of exhaust air. The room is constantly supplied with fresh air with the help of two ventilation modules that work symmetrically. The air coming from the outside passes through the needle heat accumulator, heats up and is then fed into the room through the filter. At the same time, the used air is removed from the room through the same accumulator, heating it. According to this principle of ventilation, we use up to 80% of the air heated in the room to heat the cold streams coming from the street. This unit has an elegant appearance, very similar to a window frame. It can be mounted both above or below the window, and from the sides. It is practically invisible from the outside of the building, but from the inside it fits perfectly into the design of the window. Control of the VentoTherm Twist unit is carried out using the remote control according to pre-programmed modes. Automatic ventilation can be set when a critical CO level is reached2. A built-in sensor will monitor this."
When the noise doesn't bother you
Acoustic comfort, unfortunately, often finds itself in the lowest position of the customer's and designers' priorities. Sometimes an architect ignores the soundscape or makes the unfortunate mistake of designing deep balconies that catch and amplify even minor noise. Multi-chamber packages effectively cut off external noise, but while the window is closed. However, Schüco has an answer to such a request: at the company's exhibition stand at BAU 2023 in Munich, a window with a silicone seal and a special profile was presented, thanks to which noise is cut off in the ventilation mode.
Schüco AWS 90 AC.SI is a window with a silicone seal and a special profile, thanks to which noise is cut off in ventilation mode. Photo: Schüco Deutschland
Oleksiy Sverchkov: "Sound insulation is very important, especially when it comes to buildings located near busy highways, railways or the airport. Urban noise is not only an inconvenience, but also impairs the quality of life and, if you are constantly exposed to it, can lead to diseases. The WHO (World Health Organization) document on noise pollution states that it is one of the most important environmental hazards for the physical and mental health of the population. While we do not pay due attention to this problem, noise pollution maps are already being created in many world capitals. Combating noise is a complex task: on the one hand, it is necessary to eliminate its sources, and where this is no longer possible, to use means and methods of combating its consequences.
This is a constant dilemma: close the windows for soundproofing or open them for ventilation?
A constant dilemma: close the windows for soundproofing or open them for ventilation? Our company presented a solution: it is an acoustic window AWS 90 AC.SI, which can be opened for ventilation, leaving the annoying traffic noise outside. Schüco AWS 90 AC.SI is the optimal solution for buildings in noisy environments.
Particularly sensitive rooms like bedrooms and children's rooms located on the exterior side of the facade can be naturally ventilated with this window system and there is no need to worry about traffic noise.”
A combined sun protection system is implemented on the facade of the Schüco One office building, designed by 3XN studio. Image source: schueco.com
Schüco One as a manifesto and embodiment of virtues
Climatology in architecture is an important cross-disciplinary field, but relatively new. You can count on your fingers the examples when all innovations are implemented together in one facility. The new Schüco headquarters building on the Bielefeld campus, opened in autumn 2022, will be the first building in the world to receive three sustainability certificates: LEED, BREEAM and DGNB (Deutsche Gesellschaft für Nachhaltiges Bauen - the German national certification system). The use of recyclable materials and package sustainable solutions, as well as the implementation of the "New work" concept, have turned Schüco One into a symbol of innovative orientation.
The pleated design of the facade prevents overheating of internal spaces by reflecting direct sunlight
The credo of the authors of the architectural project, the Danish bureau 3XN Copenhagen, sounds like Architecture shapes behavior — "Architecture shapes behavior", so the starting points of the design were the comfort of employees and the corporate principles of the client company.
The organic form of the seven-story building with alternating transparent and opaque blocks is dictated by the desire to create an expressive individual image, but not only that. The pleated design of the facade prevents overheating of internal spaces by reflecting direct sunlight.
Open workspaces lead to a central atrium that rises to the full height of the building. The skylight uses SageGlass® electrochromic dynamic tinted glass, which darkens on bright sunny days, preventing the sun's heat energy from entering, but allowing light to pass through.
The lobby of the Schüco headquarters in Bielefeld, Germany.
The complex undulating shape of the balconies opening into the atrium and the noise-absorbing surface treatment dampen sounds and allow you to create acoustic comfort, which is usually a problem for open offices.
Sun protection on the windows is provided by the built-in Schüco Integralmaster electrically controlled internal roller blinds and the Schüco CSB front sun screen integrated into the facade from the 1st to the 6th floor. This allows for coolness and guarantees no glare on workplaces and computer screens, but preserves the transparency of the windows.
The lobby of the Schüco headquarters in Bielefeld, Germany. Photo: Frank Peterschröder
Despite the fact that, according to European standards and definitions, the microclimate is considered favorable if it suits 80% of the people in the building, the designers decided to abandon completely centralized management and give employees the possibility of individual control and regulation. Schüco One implements a flexible hybrid microclimate control system. Sun protection, lighting, heating and ventilation are controlled centrally with the help of artificial intelligence, which chooses the optimal scenario taking into account the time of day and the weather. At the same time, employees can independently manually open windows for ventilation, raise and lower blinds in each of the workspaces, depending on personal preferences. On the third, fifth and sixth floors of the building, as well as on the roof, there are open terraces where employees can work or relax in the fresh air.
A visit to Schüco One, which set a new quality bar for an office building in Europe, made us think about how scrupulously and attentively the architects and the customer approached the concept of "comfortable microclimate", creating an architectural object that can be considered a kind of manifesto of a responsible and sensitive attitude to users. Continuing the series of materials in partnership with Schüco, in the next article we will touch on an even more sensitive topic and talk about new technologies in the field of barrier-free solutions.
Schüco representative office in Ukraine
Kyiv, str. 15 A, Leipsizka (2nd floor)
tel. + 38 044 490 68 37
www.facebook.com/schueco.ukraine
