Auf dem Foto sind mehrere Fensterelemente in der Freibewitterung zu sehen.

ift Rosenheim – 50 years of service to the industry

Part 10 (time slot 2011 - 2015): Sustainability and environmental impacts of construction elements

Reading time: 1 minute

In 2016, the Insitut für Fenstertechnik e.V. (ift Rosenheim) is celebrating its 50th anniversary. According to the motto ‘ift Rosenheim – 50 years of service to the industry’, the technical development is presented in a ten-part series of articles. The individual articles are reflecting timeframes of 5 years from founding of the institute. They enable a short glance at the events at that time, take up as a key aspect a pioneering research project at that time, summarize goals, contents as well as results, then illustrate the further development as well as the impact thereof on the industry, and the current state of the art.

Sustainable use of resources and environmental control


Further basic requirements such as recyclability of building material as well as the evaluation of environmental impacts of buildings came along with the new Construction Products Regulation. Therefore, the research work of ift Rosenheim focused on the environmental impacts of construction elements and sustainability assessments:

  • Emissions of windows and internal doors
  • Erosions of building elements
  • Environmental Product Declaration for transparent construction elements
  • Recycling concepts for wooden windows

Many sustainability certification systems for buildings such as LEED, BREEAM, BNB and DGNB demand from the manufacturers product information describing important criteria of sustainability for the entire product life cycle.

The determination of the environmental impacts is made within an Environmental Product Declaration (EPD) according to DIN ISO 14025 and EN 15804. Therefore, a Product Category Rule (PCR) is necessary that determines reasonable boundary conditions and methods for the product groups.

Research project

Product category rules and environmental product declarations (EPDs) are issued in the project “EPDs for transparent building components” [1]. Previous environmental product declarations cover only a part of the life cycle, mostly the “cradle to gate”, i.e. from the cradle to the factory gate. Aim of the research project was to depict the complete life cycle “cradle to grave”. Furthermore, ift Rosenheim examined and evaluated the emission potentials of windows [2] and internal doors [3].

The inspections for the research project “Erosions of building elements” [4] was made in natural weathering test (image 1) at a representative selection of complete window elements. The analysis of the rainwater running off was made regarding various chemical test parameters. In addition, representativ single components made of wood, plastic, metal and glass were examined in the laboratory.

Auf dem Foto sind mehrere Fensterelemente in der Freibewitterung zu sehen.
Bild 1: Fensterelemente in der Freibewitterung

Realization in the industry

Life cycle assessments and sample EPDs were issued for the complete life cycle of windows as well as glass products. Within the project, PCRs are developed for windows and doors as well as for flat glass in construction engineering and released by IBU committee of experts.

The PCR provides general rules for the compilation of Environmental Product Declarations. The PCR have the same structure as a regulation or a guideline. Within an EPD, mandatory statements are only required for the production.

Furthermore, representative scenarios of windows and doors were created over the complete life cycle. The life cycle of the building can be rated with the obtained data.

Auf dem Schaubild ist erklärt, welche drei Dinge es braucht, damit ein Gebäude zertifiziert ist. Nähere Informationen zur Darstellung erhalten Sie auf Anfrage unter +49 8031 216-2150.
Bild 3: Ablauf Gebäudezertifizierung

Also the suspicion has grown that windows and doors are jointly responsible for health problems due to emissions. In future, an evidence for all possible emissions relevant for indoor air has to be given for products subject to CE marking.

No European harmonized method of evaluation is available for their evaluation. In addition to the private identification systems, some European states have their own regulations and methods of evaluation that are not part of the CE marking. However, if products are put on the relevant markets, national requirements have to be fulfilled.

Measurable erosions could be determined. Except for biocide propiconazole and phenol index, the determined eluate concentractions were mainly in the area of background values or below the determination limits of analytical measurement methods.

An evaluation of a possible risk potential is not possible due to not (yet) defined assessment models. In any case, the industry can use the research work to question the respective product portfolio regarding the erosion potential.

Sustainable building

Sustainable use of natural resources

Most of the actors saw the UN climate conference COP 21 in Paris as a breakthrough in climate policy with the aim of reducing greenhouse gas emissions. One way of doing that is intelligent product design and a new thinking regarding the product life cycle. Furthermore, the 3 Rs of the COP 21 are:

  • Reduce (reduction of the resource consumption)
  • Reuse (reuse of products)
  • Recycle (recycling)

At the building level, sustainability regarding ecology, economy, sociocultural as well as technical quality is considered the complete life cycle. In Germany, the idea of sustainable building was already pursued in the 90s. As a result, the guideline sustainable building with instructions for sustainable evaluation of buildings considering the complete life cycle was written.

Hygiene, health and environmental protection

“Hygiene, health and environmental protection” are defined as basic specifications of building elements by the Construction Products Regulation. The main focus is on two different types of release of materials.

The release of volatile organic compounds (VOC), which come off construction products into the room air and can be absorbed through breathing, is considered as “emissions in the room air”. The assessment of this topic is extremely complex. The aim is to ideally exclude the consequences on health and well-being of the occupant.

The release of hazardous substances, which dissolve from the construction elements under the influence of UV radiation with rainwater running off and can enter in layers of earth and waters, is considered as “erosions in soil and groundwater”. The aim is to save the soil and the groundwater from these influences.

State of the art

Sustainable use of natural resources

Due to sustainability assessments of buildings and their components, not only single values for thermal insulation, air tightness, etc. specify the product, but the questions to the complete life cycle of

  • Material usage (production, energy consumptions during transportation,...)
  • Production (water consumption, carbon emissions,...)
  • Use (maintenance cost, service life,...) and
  • Exploitation (disassembly, recycling,...)

In addition to the technical characteristics, sociocultural factors extend the range of assessment such as design, comfort (thermal comfort in summer and winter), convertibility and accessibility.

Hygiene, health and environmental protection

The European harmonised standard specifies regarding the emissions of construction elements how to treat construction elements in general. The actual test methods have been standardized for years. So far, product-specific specifications for sampling or design of test specimen.

However, an European harmonised method of evaluation is being prepared at high pressure. An agreement and thus a basis for the declaration within the CE marking can be expected soon.

Methods for testing have been developed on European level regarding the erosions of construction elements. It is still open how these methods can be used for windows, facades, gates, etc.

An evaluation of the erosions is still not possible. There are different specifications that have to be consulted for the quality of groundwater. However, these limits cannot be used for the point of appearance at the building corner and/or in the laboratory.

Die Tabelle zeigt und beschreibt zehn Nachhaltigkeitsindikatoren. Nähere Informationen zur Darstellung erhalten Sie auf Anfrage unter +49 8031 216-2150.
Tabelle 2: Nachhaltigkeitsindikatoren [2]


Sustainable building is practiced more often and also the community would prefer more transparency in the purchase of new products. Terms like EPD, VOC, cradle to cradle are no longer foreign words in the industry, as many manufacturers of building components think about the impact of their products on the environment. Furthermore, the sustainability is moving into focus of the consumers, whereby all products have to be transparent and assessable.

For emissions as well as erosions, there could not be given one hundred percent all-clear signal for the tested construction elements. The detected quantities of hazardous substances were very low, but still traceable. An assessment criterion is still discussed on European level. It is still not clear whether further evidences are necessary for windows, doors and facades. Further research needs and need for optimisation is given, in any case.


  1. von Houwald, B.; Wortner, P.; Kreißig, J.; Peters, H.:
    EPDs for transparent construction elements

    Research report of ift Rosenheim, 2011
  2. Bliemetsrieder, B.; Wensing, M.:
    VOC emissions of wooden windows
    Research report of ift Rosenheim and WKI, Braunschweig, 2013
  3. Bliemetsrieder, B.; Wensing, M.:
    VOC emissions of internal doors
    Research report of ift Rosenheim and WKI, Braunschweig, 2011
  4. Bliemetsrieder, B.; Kaube, M.:
    Erosions of building elements
    Research report of ift Rosenheim and Fraunhofer-IBP Holzkirchen, 2016
  5. ift-Guideline NA-01/3
    General guideline for preparation of Type III Environmental Product Declarations
    ift Rosenheim, August 2014

Gabriele Tengler

ift Rosenheim

Dipl.-Ing. (FH) Gabriele Tengler as assistant head of PR & Communication and employee at ift Rosenheim since 1978. In addition, responsible for many years for the Technical Hotline and for more than 20 years for the organisation of the Rosenheim Window and Façade Conference. For more than 35 years now, she takes care of the public relations at ift to process the compiled knowledge target-specificly and to provide it to the industry.

Benno Bliemetsrieder

ift Rosenheim

MBA, Dipl.-Ing. (FH) Benno Bliemetsrieder is working since 2007 at ift Rosenheim. In the area Research & Development, he was entrusted with the management and processing of various research projects (surface treatment technology, window constructions, VOC emissions, erosions). Since 2015, he is working as project coordinator of the management of ift Rosenheim.

Solutions related to this topics

Articles related to this topics