Evaluating The Environmental Performance Of Stick Curtain Wall Systems

A Comparative Life Cycle Assessment Approach Applied on an Office Building in Munich



The construction industry is one of the greatest sources of pollution, where 39% of global energy-related carbon emissions are attributed to buildings’ direct and indirect emissions (UNEP-SBCI 2017). Facades have a high influence on energy consumption during the building life cycle and, consequently, contribute to buildings' CO2 equivalent emissions (CO2e). This paper examines the influence of varying design parameters to enhance the environmental performance of stick curtain wall systems. The environmental performance is determined by measuring the curtain wall system's contribution to the building's operational energy consumption and assessing its global warming potential throughout its whole life cycle. The curtain wall contribution to building operational energy consumption in terms of heating and cooling demands (kWh/year) was calculated through an energetic analysis using EVEBI Pro software. A whole life cycle assessment (WLCA) from cradle to cradle was carried out to define the global warming potential (KgCO2e) using OneClick LCA software. The first design parameter is the glass type and thickness, including the existing 56mm TGU and three other variants, 44mm TGU, 27mm DGU, and 24mm DGU. The second design parameter is the profile material and system, including the existing profile VISS 60 steel and two variants, FWS 60 aluminium and AOC 60 timber. The results indicate that reducing the curtain wall glass thickness from 56mm to 44mm would reduce the embodied carbon emissions almost by half and slightly impact the operational energy consumption related to heating and cooling demands. Also, using 27mm DGU instead of 24mm DGU would significantly reduce the curtain wall’s WLCA. Regarding the other parameter, the comparison shows that the baseline VISS 60 steel profile system has the lowest global warming potential, followed by the AOC 60 timber and FWS 60 Alu systems.


Photo of Dima Othman

Dima Othman

B.A.Ing., M.Eng., LEED AP

Hochschule Ostwestfalen-Lippe


Photo of Daniel Arztmann

Daniel Arztmann

Dipl.-Ing., M.Eng., EFN, FTI Professor for Façade Construction, Technische Hochschule Ostwestfalen Lippe (TH-OWL) Head of Building Physics,

Schüco International KG




The earth's average temperature has increased about 2 degrees Fahrenheit during the 20th century (Jackson 2021). Immediate actions are necessary to limit the effects of global warming. The construction sector is a significant contributor to earth's problems, emitting 38% of global energy‑related CO2 emissions (UNEP-SBCI 2017). The operational emissions from energy use account for 28% and 11% of the embodied carbon associated with material production and construction (WGBC 2021).

Facades play a major role in buildings energy consumption as they are the interface between the building and its environment and controlling the interaction between them (I. Lee and Tiong 2007). They contribute at least by 16% to the total building embodied carbon emissions (Climate Emergency Design Guide 2020). To reduce both building’s energy consumption and carbon emissions, it is fundamental to

introduce a design approach based on circularity considering every stage of their life. In specific, developing practical assessment tools to measure the circularity potential of building components. (Heesbeen, Zabek, and Hildebrand, n.d.).

Background: LCA Application on Building Envelopes

A Life Cycle Assessment (LCA) approach has been used to assess the environmental performance of various industrial products, but there are a limited number of studies that focus on curtain

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Method: Whole Life Cycle Carbon Assessment

An integrated approach was introduced to evaluate the influence of varying design parameters on the environmental performances of a curtain wall system. The environmental performance is determined first, by measuring

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Data and Results

The LCA results illustrated in (Table.14) and (Table.15), indicate that using the baseline curtain wall VISS 60 steel profile system achieves the lowest carbon emissions from cradle to cradle among

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Explanation and Interpretation

The following section summarizes and analyzes the achieved results in the LCIA phase to aid decision making with addressing recommendations and research limitations. To achieve this, the contributions of each

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Conclusion and Future Work

An approach to analyze the influence of varying design parameters on the environmental performances of a curtain wall system was defined, first by measuring the curtain wall contribution into building

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The authors would like to thank all the academic faculty from the TH-Owl and the industrial professionals from ARUP. Special thanks to Laura Craft, a senior façade engineer in ARUP Berlin who supported this work through constant guidance and practical recommendations in façade engineering and its environmental performance.

**“All photos and diagrams by the author.
**The number of words is 3754 excluding tables and references.

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