Elena Seghezzi. Façade optimization is a promising approach to reduce cost and improve production control in the building sector, especially considering complex buildings. In many cases, this optimization is focusing on energy and comfort aspects, with the goal of improving daylight quality and reducing energy consumption. These approaches represent a valuable support to façade design and engineering. However they lack consideration of construction and production related issues. The goal of this paper is providing a methodology properly supporting façade optimization in a DfMA (Design for Manufacturing and Assembly) perspective. DfMA has proven to facilitate offsite manufacturing, lowering costs and improving speed and quality of construction, especially combined with BIM strategies. A BIM-based methodology can help in setting parameters for the proper optimization of the façade, balancing production related needs and design requirements. The proposed method allows the exploration of alternatives (known as Design Optioneering) to optimize the choice of façade elements. This method is based on a mathematical algorithm and script including parameters related to geometry, production waste management and designer’s needs. The proposed methodology has been tested on a newly built school in Northern Italy.

1. A BIM-based approach to façade
optimization: geometrical, economic, and
production control in a DfMA perspective
Politecnico di Milano
Department of Architecture, Built environment and Construction engineering (ABC)
Politecnico di Torino
Department of Structural, Geotechnical and Building Engineering (DISEG)
Giuseppe Martino Di Giuda, Gabriele Masera, Valentina Villa, Elena
Seghezzi, Paolo Ettore Giana
DEEC – 9th November 2017 – Cagliari

2. Problem setting
provide an optimization of
geometry, cost and production
control of façades

3. Optimization
Achieving the best measurable performance under
given constraints, based on design variables
Contour lines of objective function
Infeasible domain Design variable 2
Design variable 1

4. Current approaches
Structural optimization
Efficient use of materials, light structures

5. Current approaches
Energy optimization
Transparency
Thermal
requirements
Indoor comfort
Solar shading

6. Problem setting
Design requirements
energy related
architecture related
comfort related
Construction requirements
cost related
production related
waste related

7. Innovation: a DfMA perspective
Design for Manufacturing and Assembly
Design for Manufacture
Estimation model of production
cost and sensitivity analysis
related to the variation of design
and process parameters
Design for Assembly
Structural models for the estimation
of the efficiency of assembly
processes and possible
improvements

8. Innovation: a DfMA perspective
Simpler solutions
Higher quality
Costs decrease
Less labour on site
Easier
communications
Quantitative method

9. Design optioneering

10. Case study: the school of Melzo (Italy)

11. Case study: the school of Melzo (Italy) t=0d
t=180d

12. Parameters setting
α + β + γ + δshape cost waste
number of
modules

13. Algorithm setting

14. Rainscreen façade design optioneering
Base perimeter
Family of the module
RGB colors
Module width

15. Algorithm setting

16. Rainscreen façade design optioneering
White panel
Black panel
RGB panels

17. Data coherence

18. Rainscreen façade design optioneering
80 %
70%
75%
90%
Technology, design and production related requirements 1
2
3

19. Rainscreen façade design optioneering

20. Conclusions
Flexible approach
Comparative evaluation on a
quantitative base
Traceability of decision process
Iterative process
Tailored solution

21. thank you
Politecnico di Milano
Politecnico di Torino
giuseppe.digiuda@polimi.it
gabriele.masera@polimi.it
valentina.villa@polito.it
elena.seghezzi@polimi.it
paoloettore.giana@polimi.it