Collaborative Methodology for Fastracking Challenging Facade Concepts





The goal is to explore the role and methodology employed between the architect and engineer as they look to resolve the opposing demands of design aesthetics and performance. The challenge under review is to resolve the architectural requirement for transparency with the demand for an efficient and effective means of controlling the climatic extremes typical to the projects location in the Qujiang New District of Xian, PRC.

Through the early use of conceptual 3D energy modeling techniques and direct feedback the design team could quickly confirm their initial concept and from there determine the appropriate selection of façade materials and natural ventilation controls. This can be further tested and tuned throughout the design process to match the technical, economic and schedule restraints common to Chinese construction methods and building code demands.

The resulting multi skin façade solution can be fully modeled and its performance calculated in order to fix the building energy loads, prove the efficiency of the system while maintaining the visual requirements. The early integration of design and engineering through a series of energy modeling scenarios can be demonstrated to effectively resolve what initially may be seen as an irrational and irreconcilable concept.

The Challenge

Figure 1: Cinema lobby above the entrance to the South Parcel mall of Honey City.

The client’s requirements for the Cinema Glass Box raised several challenging issues. These were defined by

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Initial Response

The client was reticent to appoint a specialist directly so the design team (GBD + BSA) had to agree to an initial study with very clearly defined aims:

Early feedback to

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Further Investigation

The expression ‘multiple skin façade’ (MSF) covers a whole myriad of façade typologies, however we will restrict this to the following description:

‘A multiple skin façade is a building envelope construction

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Glazing and Facade Analysis

Commercial buildings with high performance façades are very energy efficient buildings. The challenge in designing a building with such a unique enclosure is to fully understand the physics of the

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Calculations to Determine the Optimal Ventilation Opening

Multiple skin facades provide a good example of the occurrence of pressure differences. As a result of insolation, the air in the cavity between the two skins becomes warmer than

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Figure 7: Results for the month of July. The MSF has a 96 kW LED installed in the cavity.

The temperatures in the cavity are important as the MSF absorbs a

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Energy Load Calculations

The aim of a well-designed MSF is to reduce the energy consumption of the space it encompasses. This MSF was designed to reduce the energy consumption of the lobby, which

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The energy modelling proves the performance benefits of the MSF over a standard façade approach:

The MSF allows the use of ultra-clear external glass to maximize views of the LED

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Preema Modi for all her graphical work.

Rights and Permissions

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