## 2 Overview  
### Origami on AEC Sector  
The Architecture, Engineering, and Construction (AEC) sector must adapt to meet this challenge. In order to do so, new opportunities are opening through innovation, such as the use of Building Information Modelling (BIM) together with digitalisation and Internet of Things (IoT) [8; 9; 10], the use of metamaterials [11; 12], and the use of programmable origami-based properties that allow mechanical unfolding. In this regard, the use of these singular elements is no longer only applied to achieve an impressive geometry in roof elements, mobility and automatization for energetic and functional purposes are also considered [13]. Therefore, the new design concepts tend to focus on adapting to the environmental climatic conditions and their changes, obtaining more competitive advantages. Energy efficiency becomes a key factor at the design phase. Wind and solar radiation are some examples of meteorological conditions that may rethink the projects to be designed and built in the following years. On the one hand, there are the high winds that carry sand from the desert. This causes a number of catastrophes in Arab countries, such as the covering of railway tracks, roads, or impact against building fronts. On the other hand, solar radiation can cause temperatures in buildings to rise up to alarming and sometimes unfeasible levels, e.g., curtain walls can reach temperatures of up to 80 \({}^{\circ}\)C, forcing to the use of indoor air cooling [14]. Therefore, this possibility represents a great opportunity to reduce CO2 emissions into the atmosphere. The use of facade elements that fold or unfold depending on the project location and the season of the year can reduce energy consumption as has been shown in previous published research [1; 2; 3]. Considering a folded position, an improvement of natural light usage instead of artificial lighting is possible. Moreover, half-folded or totally unfolded important heat transfer is reached allowing to decrease the use of air conditioning. There are examples of buildings with adaptable building facades in the world [15], or Origami implementations for shape optimization considering structural performance [16]. Figure 1 shows some of the most prominent applications in this field [17]. These projects were characterised by a dynamic adaptation of facade elements to external conditions. An example is the Kiefer technic Showroom built in 2007, with a fully automated facade control system. Each user has control over the facade element which affects only to the internal user space. Syddansk Universitet in Denmark holds a system that regulates the interior temperature according to the external climatic conditions. The One Ocean in South Korea uses natural materials that are susceptible to deformation depending on external conditions. Lastly, the Al Bahr Tower was built between 2009 and 2012 in Abu Dhabi, reaching 147 metres high. This building, due to its height and the important sun radiation along the day, was designed with intelligent facade based on origami techniques. This concept allows to each facade element to modify its geometry according to the sun position, reducing carbon dioxide emissions in the order of 1750 tonnes per year [18]. However, obtaining all information regarding temperature, humidity, ventilation, lighting, or even occupant behaviour is not so simple. There are discrepancies between simulation predictions and real energy use [19]. Designing efficient energy buildings with good indoor environment involves elements of expertise derived from multiple disciplines such as architects, civil, mechanical, and electrical engineers. Consequently, BIM is being increasingly used to design buildings. The integration of design and management in a single tool allows a faster and more flexible design process, enabling and easing the production of multiple alternatives that also consider the conservation and operation of  
Figure 1: Origami applications on the AEC sector. the building, in both construction aspects and energy savings [20; 21].