During its anniversary year, the windows and facades industry takes up new tasks
The world is in a state of transition – increasing energy and electricity prices as well as the intensive discussions on solutions for climate change and the energy strategy demonstrate this. The windows and facades industry is in the limelight of this development and in the focus of builders, who wish to optimise their real estate properties and/or build or refurbish them in a manner which enables value growth. On October 11th and 12th, technologies and explanations on this topic again brought almost 1,000 experts from 27 countries to the International Rosenheim Window & Facade Conference, the largest trade congress of the industry across Europe. The conference proceedings including more than 170 pages and 700 lecture slides on CD-ROM may be ordered online.
“We must introduce the age of regenerative energy recovery to our industry as well, and to achieve this, we must develop further leaps in technology”. With these words, the director of the Institute, Professor Ulrich Sieberath, on whom the title of honorary professor was conferred by the University of Applied Sciences Rosenheim during this festive evening, put the task of the industry in a nutshell. It is essential to demonstrate to consumers and politicians that windows and facades with a gross solar efficiency level of more than 60 % are an indispensable building element for the energy plus buildings required. He requested the industry to move away from the U value Olympics towards a holistic planning, consulting and product development for windows and facades.
This also includes the active and competent handling of subjects such as ventilation, shading, daylight supply, photovoltaics, building automation and comfort of living. Constructing buildings so that they are sustainable and capable of adapting to demographic change also plays an increasingly important role. Adapted to demographic change not only means that buildings and construction elements are energy efficient and gain more energy, but also that they may be used easily, safely and comfortably by the young and the old as well as by persons with and without handicap alike – it is only this that assures real estate with value growth, which may be used reasonably or sold even 20 years from now. “We have reached the limits on thermal insulation and we need innovations and real technological leaps, since the optimisation of our constructions today cannot bring us forward”, explains Ulrich Sieberath. Vacuum glazing, the development of temporary components for heat protection and the storage of excessive solar energy recovery in the construction component or in the building provide some approaches for this purpose. Windows and facades must have a modular construction for their design and manufacture, so that the constantly rising demands on construction components do not lead to over-priced products that cannot be sold. This also includes the development of appropriate installation designs, with which the efficiency, quality, and technology, too, can be significantly improved. However, this is nothing new in this industry – as a short review of the topics and lectures of the past 40 years of the International Rosenheim Window & Facade Conferences demonstrated.
In the group of topics, Refurbishment and Modernisation, the participants were waiting excitedly for the lecture of Peter Rathert, the Head of Division of the BMVBS, (Bundesministerium für Verkehr, Bau- und Stadtentwicklung, Federal Ministry of Transport, Building and Urban Affairs) who introduced the cornerstones of the EnEV 2013. Based on the efficiency principle, the revision will be very moderate overall, but shall be made more stringent in two stages (2014 and 2016) and again provides for a step-by-step decrease of 12.5% in 2014 and again 12.5% in 2016 of the permitted annual primary energy demand QpH for new buildings. The other constraints about the transmission heat loss H´T shall be decreased in two stages of about 10% each on an average; varying however, according to building type. In concrete terms, this means stringency between 5 % and 30 %. The summer heat insulation of buildings is explicitly included in the EneV – not only as a reference to DIN 4108-2. This will lead to stringency of summer heat insulation of buildings according to Peter Rathert. The EnEV shall be introduced in the policy-making committees together with the changes of the EnEV and will become applicable with effect from the 4th quarter of 2013.
The topic Window Ventilation has established itself as a permanent topic. This is why Norbert Sack of ift Rosenheim, as the Project Manager of the associated research project, presented the options on how a window builder can make the ventilation planning required by the building law simple and safe. Two ift guidelines, one online tool as well as appropriate seminars are available for this purpose.
The group of topics, Universal Design (UD), demonstrated very emphatically the enhanced significance associated with sustainable planning and product development not only for entrepreneurs but also for builders. Thomas Bade, co-founder of Universal Design e.V., coined the term “demographiefest” (demography-proof or capable of adapting to demographic change), which means that the usage of buildings, construction elements and products for all kinds of user groups is easy, safe and comfortable, that is, even as the residents of a building grow older. This already has a direct impact today for the preservation of value (sustainability) and the financing of real estate property. For buildings that are not energy efficient or barrier-free or prepared for demographic change, not easily adapted to changing demands and residential requirements, cannot be easily sold and even today are financed by banks with higher interest rates. Ulrike Rau of the architecture offices raumkonzepte translated the philosophy of Universal Design into practical use and emphasised the importance of the design and implementation of barrier-free buildings. It is not only the consideration for the elderly and the handicapped but living in general becomes more comfortable and safer for all. DIN 18040, barrier-free building has been introduced and clear requirements have been formulated, even if they still are not adhered to, such as the omission of thresholds. For windows and doors, this primarily concerns operating elements, for example, handles, which can be reached and operated easily, which is why the operating force must be limited to a maximum of 25 N. But even the design of construction components including the operating elements according to the two-sense principle means e.g. being able to see and feel functional parts or to see and hear them respectively. Did Susanne Gosztonyi of the Austrian Institute of Technology finally carried off the audience to a distance or nearby(?) future of a bionic building shell, copied from Nature and in an ideal way adaptive, sustainable and energy-efficient. There are numerous models in Nature pertaining to this. It is not only the lotus flower or the gecko that we can learn from. Not only was the transfer method of the analogous search in biological databases presented, with the help of which 240 biological models were identified for facades, but also 28 concrete bionic draft approaches for innovative facades such as a two-dimensional distribution of light or fibres which conduct light, as they are being used by the Venus' Flower Basket (Euplectella aspergillum), which exists in the Western Pacific.
In the group of topics, Business Practices and Management, concepts were introduced on how approaches to improve the quality change in enterprises as well as on site. Josef Steretzeder of the Institute for sustainability, environmental and energy management reported on a test that has been completed to fathom the CO2 neutral production at an industrial site in Germany. The analysis of the material consumed resulted in a reduction potential of 17%. In connection with the use of regenerative energy the maximum amount of CO2 reduction is 50%. The rest is possible only with compensatory measures and the associated reduction of CO2, for example, reforestation programmes. Professor Andreas Fuchs of the University of Applied Sciences RheinMain, dedicated his lecture to new concepts for the refurbishment of facades in non-residential construction, which many businesses and property owners shy away from not only on account of the high costs but also because of the non-availability for use. Here, it is often overlooked that modern facades can improve the working conditions considerably, especially with respect to thermal comfort, options for natural ventilation, sound protection and daylight supply. Prof. Fuchs introduced construction and process principles of modernisation facades. With a high degree of pre-fabrication, where complete facade segments are put in front of the old building shell, the impact is reduced to the installation of load anchors, sealing with the help of films and the interior fittings facing the room. The non-availability of the rooms or floors is thus limited to a few days. The overall cost calculation shows that the additional expenses for planning and pre-fabrication can easily be compensated by the costs incurred in the event of any non-availability. However, the lopsided fixation on building costs undermines an increased willingness for refurbishment. The windows and facade constructions that have become more complex, the division of labour for production and usage of the most diverse semi-finished products require the suppliers‘ parts to be inspected. Hence, the quality control required by building law and the traceability of the production conditions can only rarely be achieved by lists and specific measures even in the windows segment. Christian Kehrer, head of the certification body at ift Rosenheim, demonstrated how an integrated management system can decrease the operating expenses and improve the quality. With the intelligent combination of management systems for quality, environment, energy and occupational safety, significant synergies can be used. Data does not need to be acquired multiple times, for example, and interactions are recognised, for example, with the handling of hazardous materials and emissions, which concern the environment, the product and occupational safety alike. Special attention needs to be given to document control and archiving, since the new Construction Products Regulation stipulates the retention of documents over a period of 10 years with effect from July 2013.
The group of topics, Control and Construction, is the historic central theme of the International Rosenheim Window & Facade Conference and concerns itself with new constructions. As the Business Division Manager at ift Rosenheim, Jörn P. Lass presented how you can achieve a larger product portfolio with lower cost and effort even in window construction with the help of modular construction principles. The competence lies less in the development of individual modules having characteristic properties, but rather in the definition and design of the interfaces, with the help of which the modules become a whole. In the windows segment, too, there are definitely modules that may be replaced easily, for example, insulated glazing units with different thicknesses or features and fittings. However, the functional dependencies must be known and taken into account, for example, if the thermal insulation deteriorates by improving burglar-proof characteristics, since steel reinforcements are deployed. Overall, there is still a large need for development, which, however, is addressed by only a handful of manufacturers. Large “construction sites” continue to be the installation and connection to the building structure as well as the development of interfaces for the integration of automatic and electronically controlled construction elements in the building services engineering. The lecture by Professor Michael Krödel, who teaches Building Services Engineering at the University of Applied Sciences Rosenheim, was a seamless continuation of this topic. With the words “Mechatronics and Electronics in window construction are like the puzzle of Dalli Dalli (common German TV show in the mid 1970s)”, he got to the heart of the present situation. As a matter of fact, the industry knows that significant improvements are achieved with respect to living and operating comfort, freedom from barriers, safety and security, and energy conservation by using electronically controlled systems, but there is no progress in this direction. The involvement of various subsystems, ambiguous specifications by the designers and missing interfaces, often enough continue to lead to highly cumbersome individual planning, production and installation processes accompanied with the associated risk of failure. Hence, the most important task is the development of uniform interfaces and standardised processes. The research project, “Development of fundamentals for the integration of electronic systems in the construction of windows facades and doors" has created the associated basis for this purpose. Practical recommendations have been formulated in the ift guideline, EL-01/1 “Electronics in windows, doors and facades”. Further work and studies are being conducted with individual manufacturers based on this. The grouping of activities in another related R&D project would be one option for working out practical solutions for the existing problems and issues. With the help of fibre-reinforced concrete parts, new formwork techniques and the design and planning using 3-D software, buildings today may be constructed with bizarre free-style areas, which also place totally new requirements on the design, planning, manufacture and installation of facades. Dr.-Ing. Steffen Feirabend, presents two current projects with the “King’s Cross” railway station in London and the Art Museum, “The Board” in Los Angeles, in which concrete or steel constructions and building with glass produce an ideal synthesis. The requirements presented that are made on the facade demonstrated impressionably that each and every detail is critical and only accurate and meticulous design and planning of all installation processes, connections to the building structure and bonding agents facilitate successful realisation.
The Generic Subject of Modern Glazing Technology is dedicated to current topics on glass and glazing that the manufacturers of windows and facades must be aware of. Karin Lieb made the beginning, who, as the Business Division Manager for glass and building materials at ift Rosenheim, demonstrated the limits and deployment options of triple-layer glazing. Triple-layer glazing units have become standard glazing as a result of the enhanced energy-related requirements and are used in the most diverse applications. However, owing to the larger edge seal and the greater total thickness as well as the increased weight of the glass, there are also other stresses and limitations on the applications, which the window and facade builder should know in order to avoid loss or damage. The increased climatic loads form another critical case and in the case of smaller formats of the glass panes, these loads may lead to enhanced stress and premature failure of the edge seal – the consequence is the ingress of moisture, which is also called a “dummy” pane. This is why ift Rosenheim is working out application diagrams in a research project, with the help of which the critical dimensions can be determined. Professor Benno Eierle from the University of Applied Sciences Rosenheim and Harald Krewinkel from ift Rosenheim presented new options for the verification of safety barrier glazing that are possible with the help of the new DIN EN 18008-4. Apart from the popular pendulum impact test, a simpler form of verification is also possible using tables. What has been added recently is the verification with the help of simulation calculations using FEM (Finite Element Method) software. However, the method places high demands on the software requirements and on the engineers who use it. At present, ift Rosenheim is working out the basis for the validation of software products in a research project. In the process, ideally speaking, ift can fall back on the comparison of the results of the calculations with the test results. Professor Franz Feldmeier from the University of Applied Sciences Rosenheim dealt with the subject of Evolution of Multiple Skin Facades, which form one approach towards the solution of undertaking advanced technological development for windows, facades and glazing units. The constructive solutions of windows & facades and insulated glazing are coming increasingly closer to one another, (just think of tripe-layer glazing with sunshade elements in the intermediate space between the layers). A technical hurdle still present so far is the increase in the climatic loads resulting from the larger intermediate space between the layers, and which may quickly lead to an edge seal having leaks and thus, to a defective insulated glass unit. If this problem gets resolved, it would be possible to introduce a genuine functional layer in insulated glass. With this, applications such as sunshade, light deflection or even media functions could be realised. These glass units are also referred to as closed-cavity facade and can easily be integrated in window and facade systems. This is why a research project has also just been kicked off at ift Rosenheim on the development of pressure released insulated glass units.
The group of topics, Market & Trends, has been a highly popular one since a few years, primarily with strategically and commercially motivated participants, since significant trends and market opportunities are presented here. Professor Christian Niemöller presented the impact of the Construction Products Directive (BauPV, Bauproduktenverordnung), on the CE marking, the factory’s internal production control and other adaptation processes necessary for a company, such as, for example, document control. In particular, the introduction of the “Performance Declaration” is a central aspect since new and far-reaching liability risks come up. The performance declaration is not only a mandatory prerequisite for the CE mark, but also a binding description of the characteristics or properties assured. Even the rules and regulations on the CE mark get amended and are an element of the unique identification of the manufacturer on the product, as well as the traceability of the product characteristics including the associated verifications for a period of 10 years. Especially in commercial construction, the demand for sustainability certification according to LEED, BREEAM, DGNB and BNB is growing to identify and utilise both the corporate image and the potential for optimisation. Apart from minimising operational costs, even the intrinsic value and sustainability of the real estate property form the decision-making criteria for the pros and cons of certification. Dr. Birgit Memminger-Rieve is conversant and well-versed with all certification systems and presented the evaluation criteria as well as the market significance of the certification systems prevalent in the market. The systems are undergoing advanced development; thus, the English BREEAM has become more technical and is gaining in international significance, since it takes reference to the minimum national requirements. In contrast to this, LEED refers to US requirements. At present, BREEAM is an effective certification system for the refurbishment segment, since certain criteria, which cannot be changed in an existing building, may be excluded, for example, the connection to public means of transport.
In his lecture on Premiumbauen 2012 (Premium Construction 2012), Martin Langen from B+L Marktdaten, reveals what is behind this phenomenon. He quantified the segment in Germany for 2014 at 27,000 residential units, with the segment being characterised by substantially better construction quality. Building owners in the age group of 55 plus, and having a high level of purchasing power are behind this segment, as well as childless couples (DINKs = Double Income No Kids) and they would like to refurbish their real estate property. Both target groups will grow in the years to come and will thus be an increasing and structural trend for the next 10-15 years. However, what needs to be noted is that these customers work intensively to get acquainted with the subjects pertaining to construction and have a high level of interest in matters of windows and facades. What is interesting is that these building owners prefer to have construction work executed by qualified companies employing craftsmen: hence, this is an important sales channel for the manufacturers. This is primarily true of wooden and wood-aluminium windows, which are the largest frame material group in this segment enjoying a market share of over 50 %.
The group of topics, Identify and Prevent Loss or Damage, in the meantime, has developed into a fixed parameter for the pragmatists, since the most frequently occurring damage to windows and glazing units including the associated causes are analysed here. Werner Stiell, Manager of the ift Expert Centre, began with the presentation of typical errors based on several examples, and with tips on how these need to be avoided. Example 1 illustrated the problems faced in sealing off penetrations into windows, facades and conservatories. Since penetrations into the level of protection against bad weather can be sealed off permanently only with great difficulty, these should basically be prevented, or design-based drainage of the water that penetrates must be planned. Another example was concerned with the compatibility of materials. With the so-called base sealing of windows, in which the glass rebate inside is sealed off using a sealing agent, in addition to the glazing bead, there are reactions that take place time and again with the outer or external seal of the edge seal of the insulated glazing. The sealing agent dissolves and runs down visibly on the inside of the insulated glazing. To prevent this, the manufacturer of the sealing agent must verify its material compatibility with the sealing agent used in the edge seal, for example, in accordance with the ift Guideline DI-01/1, “Specified use of sealing agents”. Based on pictures and photographs, other typical instances of damage were presented, as well as problems of dew point performance with all-glass corners that are almost avoidable with double layer glazing. As the author of the RAL Installation Guide, Wolfgang Jehl delved into the problems and tasks associated with the installation of windows in external thermal insulation composite systems, ETICS (WDVS, Wärmedämm-Verbundsysteme). Special attention must be paid if the window needs to lie in front of the external wall for architectural reasons, for example, to be able to install larger windows. In this case, anchorage and load transmission of self-weight and live loads must be planned by making use of adequately dimensioned fixing material and brackets or butt straps. The second group of problems pertains to permanently sealed connection to the ETICS, which needs to be designed with suitable systems and materials. Verification in accordance with the ift Guideline MO-01/1 “Connection of windows to walls”, provides the assurance that the materials and the design details are effective as a system. The design in the region of the external window sills must be implemented with special care and diligence.
In the group of topics, Energy Efficiency, the topics of energy conservation and energy recovery were addressed. The ift building physicist, Manuel Demel made a detailed presentation of the different parameters on the energy balance of windows in his lecture. With the computational determination of the thermal insulation properties, you should also pay attention to the addition of the permissible tolerances and errors in rounding, so that you do not get very optimistic results while determining the total value, which, then, could never be achieved when conducting tests on the construction. As a result of the predominant focus on the U value at present, it is often overlooked that the energy recovery via windows facing the south, west and east is far higher than the losses and the windows, hence, need to be perceived also as regenerative energy producers. To do justice to this complex interaction between energy gains / losses, the overall system should be considered instead of focussing on individual parameters. This is why ift Rosenheim has also developed an energy label for windows, with which the windows may be evaluated independently of the climate, and, as a result of which, are suitable for the whole of Europe. Christian Stolte from the German Energy Agency, dena, steered the view from the details to the large whole and drew reference to the gigantic need for refurbishment in the existing buildings in Germany. If maintenance work is necessary anyway, for example, coating the facade, energy-related refurbishment always pays off. However, even refurbishment motivated from the energy perspective pays off with self-use in many cases; this is demonstrated by an analysis of building refurbishments carried out to the standard of the efficiency house 70. With the price rise expected, the investment is constantly becoming more economical. Nonetheless, the refurbishment of energy-related construction elements, particularly those of poor quality, makes sense even without this reason. This includes windows with single glazing units and old insulated glass units without coating – these make up approximately 312 million windows in Germany anyway. Apart from the energy conservation, energy-efficient buildings, in addition, are more comfortable, better to lease and more sustainable – in other words, an investment in the future for the owner and the society. Kurt Emil Eriksen from the Active House Alliance spoke on enhancing the living comfort that may be obtained by refurbishing the building – not quite insignificant, since most human beings, 90% and more, spend their lives in buildings. In the process, more comfort and less energy consumption is not a contradiction. The core requirement of active houses is that living health, comfort and covering the energy requirement by renewable energy sources are combined. Large-area windows have special importance since they assure adequate supply of daylight, utilise solar energy free of charge and permit natural ventilation and cooling down at night in the summer months.
The highlights at the end were the plenary lectures by Prof. Dr.-Ing. Ulrich Knaack from the Delft University of Technology and Prof. Dr.-Ing. Klaus Sedlbauer as the Head (Dean) of the Fraunhofer Institute for Building Physics, IBP. In his lecture, Prof. Knaack introduced “The building shell of tomorrow – Roadmap 2050”, a look into the large time spans in which path-breaking innovations have been developed by technical evolution, for example, insulated glass. Another example is the impact of the oil crisis in 1973 on the development of facades right up to the double facades and component facades of today. Components, thereby, are ventilation, air-conditioning and heating technology. In the process, he considers the development lines as the roadmap and illustrated how these have begun or may begin. What is particularly interesting, of course, is the way in which the journey progresses. Prof. Knaack sees the future of the building shell in adaptive systems, which integrate other functions and features, can respond to the influences of the environment and users and can improve energy efficiency and living comfort even further. In the transparent facade, on the one hand, this is the advanced development of the component concept, but even completely new approaches such as facade segments filled with water that are transparent, provide insulation and store heat. In the opaque region, innovative projects track the development of a concrete that gives static support, insulates and stores heat at the same time. What is interesting is also the development of Living Envelopes, behind which there is a bionic approach – in other words, learning from Nature and using natural materials that are integrated again completely into the biological circulation system. In his lecture, Prof. Dr.-Ing. Klaus Sedlbauer addressed the basic issue of what buildings and facades need to look like for the City of Tomorrow, in order to confront the continued onslaught of population growth and the global trend of urbanisation. The central focus of all considerations is the issue of how you need to build and live in the future in order to limit the consumption of resources and energy so that the consequences of climate change do not destroy our present civilisation. Resource-conserving materials, construction methods, buildings and cities must be developed for this purpose so that they generate more energy than what they consume. The enhancement of energy efficiency in the energy plus building is obtained by consistent insulation as in the case of the passive house, by system technology and the utilisation of solar energy. In the process, resource consumption gains greater weight as a result of high energy efficiency in operation, and, in fact, when other efficiency gains are over-compensated by greater use of resources. “The demand is for recycling-friendly constructions and no dismantling with the demolition ball. We need then a sustainability pass apart from the energy pass,” according to Prof. Sedlbauer. Energy storage facilities also need to be developed, with the help of which the erratic energy generation at different times of the day and seasons of the year may be buffered. This will also support further automation of the buildings and the facades. Moreover, he also stressed emphatically that we need to plan for entire cities and regions in order to utilise solar energy optimally. The balance sheet for energy and resources should then be compiled no longer at the building level, but must be prepared for entire cities. The techniques and constructions are, of course, very different depending on the climate. In cold climate regions, this is the minimisation of the need for heating energy and in hot regions with high levels of solar radiation this is the minimisation or prevention of the need for cooling energy.
The documentation volume describes the trends for 2013 in the fields of technology, science and standardisation on over 170 pages. The 27 lectures held in all at the International Rosenheim Window & Facade Conference illustrate technical solutions, market opportunities and the “Homework” necessary for the manufacturers, planners and designers, and scientists for this purpose. The conference proceedings also include a CD-ROM containing over 600 presentation slides of the lecturers. In this way, windows and facade experts who could not make it to the event, have the opportunity of being able to use and utilise this information.
Excerpts from the conference proceedings and selected slides can be found at
They are also available on an image file.
Source: ift Rosenheim GmbH