ADAPTIVE BUILDING

ENVELOPE SYSTEMS

MAY 6TH, 2021

MASSIMO STICCA & VICTORIA FIOCCO

PRESENTED TO JEFFREY JOHNSTON

BUILDING ENVELOPE (221-430-VA)

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 2

ADAPTIVE BUILDING ENVELOPE SYSTEMS……………………………………………...1 TABLE OF CONTENTS…………………………………………………………………………2 INTRODUCTION………………………………………………………………………………..3 WHY CHANGE WHAT WORKS?.............................................................................. 3-4 WHAT ARE ADAPTIVE BUILDING ENVELOPE SYSTEMS………………………5 THREE TYPES OF ADAPTIVE BUILDING ENVELOPE SYSTEMS………………………..6 SMART MATERIALS………………………………………………………………….6-7 INTELLIGENT BUILDING SKIN………………………………………………………8 RESPONSIVE FACADE SYSTEM………………………………………………………9 CASE STUDY #1………………………………………………………………………………...10 AL BAHAR TOWERS.………………………………………………………………10-11 CASE STUDY #2……………………………………………………………………….………..12 BARCELONA MEDIA-ICT BUILDING…………………………………………...12-13 CONCLUSION…………………………………………………………………………………..13

TABLE OF CONTENTS

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 3

INTRODUCTION

WHY CHANGE WHAT WORKS?

Throughout history Architects have struggled with balancing form and function when designing buildings. While aesthetics plays a huge role in making a building look nice, the function of these beautiful materials and systems could come at a cost. Adaptive building envelope systems aim to solve what seems like an everlasting issue among design teams around the world as it combines both beautiful aesthetics and functional options in respect to climate, energy consumption and occupant comfort. While some might say that the AEC industry is tried and true, new technologies have and continue to test the real-life conditions that buildings around the world undergo. This has put into question the priorities in early design stages as they have shifted from a traditional form and function method to an adaptive and high-performance outlook.

TRADITIONNAL

CONSTRUCTION

FUTURE OF

CONSTRUCITON

INTRODUCTION

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 4

As discussions about climate change and global warming are arising, designers have realized that their buildings have a significant impact on the future of our planet. According to the United Nations Environment Program: “Buildings and their construction together account for 36% of global energy use and 39% of energy-related carbon dioxide emissions annually.” 1

Building design is coming to a turning point as buildings are being designed to adapt and react to its environment all while creating a space that people occupy. The shift to greener and adaptive solutions is one that is inevitable as traditional buildings require way too much maintenance and up keeping which is very costly. New solutions such as adaptive building envelope systems allow for the use of natural resources found in proximity of the building to improve and maintain occupant health and comfort.

FUN FACT

“According to the Intergovernmental

Panel on Climate Change (IPCC) the

energy consumptions in building are

larger than the consumption for both

the transport and the industrial sector,

but they have also pointed it out to be

the sector in which the largest energy

savings can be done to the lowest cost.

Improvements in insulation materials

and mechanical system have

contributed to increased energy

efficiency but there are still

opportunities to further enhancements

when considering the entire building.

The building envelope is one of the

building elements where there are

room for improvements.”2

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 5

WHAT ARE ADAPTIVE BUILDING ENVELOPE SYSTEMS?

Adaptive building envelope systems are part of the building skin. They change and

adapt in response to the environment around them such as sun, wind, rain, etc. to

provide better indoor living conditions and reduce costs for artificial heating, cooling

and ventilation.

Traditionally, building envelopes were only used as enclosures to separate indoor

and outdoor spaces. However, these new systems are vital in reacting to the

buildings surrounding environment. This is achieved through adaptive changes in

the skin of the building: “The alteration could be achieved in various ways, by

moving components, by the introduction of airflows or by a chemical change in a

material.”3

These systems come in a wide variety of options. Some have electronics, sensors and

microprocessors and other use basic science to react to different climactic conditions.

(i.e. a certain material expanding under

heat and contracting when cooled).

The goal in adaptive building envelope

systems is to improve occupants’ comfort

and reduce maintenance costs. Many

types of systems exist to achieve this

goal. What are they? How do they work?

WHAT ARE ADAPTIVE BUILDING ENVELOPE SYSTEMS?

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 6

Smart materials can be defined whereby the characteristics and properties of this element

can be altered by an exterior stimulus like temperature, magnetic or electric fields.

Aesthetic is an important deciding factor in choosing cladding and envelope materials.

This becomes a very interesting topic as these smart materials can change and adapt in

color, form and function depending on elements such as heat and/or light exposure.

Some might say that color changing paint on the facade of a building from blue to red as

the sun hits its walls is an interesting effect, it is not very practical nor efficient. In

reality, it would not be limited to aesthetic reasons as it could take on a very efficient and

functional role. Color changing paint that would go from black (a color that absorbs heat)

to white (one that reflects it) as the sun hits the facade would greatly reduce interior

HVAC system costs and keep the interior occupants comfortable without artificially

cooling the building.

There are many readily available smart materials that are being used on existing

buildings, such as aerogel, which is applied in window glazing, thermochromics

polymer films, and structure integrated

photovoltaics.

In fact, Doris Sung from the University of

Southern California was inspired by the

emergence of these new materials and

conducted a research program on self-

ventilating skins.

THREE TYPES OF ADAPTIVE

BUILDING ENVELOPE SYSTEMS

Smart Materials

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 7

The study is conducted on the use of thermobimetals as structurally independent building envelope systems which expands, and contracts based on external temperature

changes.

The science behind the self-ventilating material is a combination of different types of metallic alloys meshed together whereby the adjoining pieces have opposing coefficients of expansion. As the heat warms the metal, it curls and creates tension with its counterpart and allows for the flow and movement of air in between the gaps. Inversely, as the metal cools, it flattens to its initial form and prevents air from passing through the surface.

“We have to rethink the way we build and

what we build with. If we don’t, our problems

will only get worse,” Sung said. “Being a

researcher in smart materials and architecture

right now is tremendously exciting. This is the

time we’re going to change our future.”- Sung 4

BLOOM INSTALLATION

Proof of concept by Sung (Free-standing prototype with the use of thermobimetals)

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 8

While smart materials can be very interesting, they remain materials which must be integrated in a system to be considered part of a well-designed building envelope. The intelligent building skin solves this problem by maximizing the system operations of a building regarding occupant comfort, climate, and energy consumption. At a very basic level, intelligent building skins could be an assembly of smart materials that form a building envelope system. At a more advanced level, we could consider physically adaptive systems such as operable windows, sunshades and even louvers. The components themselves become automated and can be installed on the building facade and collect information that is registered and accurate to be viewed later. The information gathered by these intelligent building skins can then be used by technicians to rebalance the systems in place and modify internal conditions and external performance.

Intelligent Building Skin

QUICK CASE STUDY!!

Jean Nouvels Islamic Center uses an adaptive building envelope system that mimics camera aperture lenses to control the amount of sunlight that enters the interior of the building. There are 240 photo-sensitive motor-controlled apertures on the south wall of the building controlling the amount of solar and heat gain entering the building. While this mechanism mimics traditionally Arabic architecture (as it is a learning center for Middle Eastern Architecture) all while filtering light through the building, the mechanisms themselves failed over the years through lack of maintenance and poor construction regarding durability. As the system relies on the movement of mechanical and electronic devices, the gears themselves rusted over time and ceased to work properly.

PAGE 8

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 9

While the lines between intelligent building skins and responsive facade systems are skewed, there is one main difference to take note of. The responsive facade systems can gather important climactic information and adapt to it as a whole system whereby the internal HVAC system and external building envelope system work in harmony as one. These systems are as advanced and developed as it gets as they have

properties that can change and adapt, systems that work together to form assemblies and technology built in that interacts with exterior environments in real time. All this while providing this information back to users and using AI to learn patterns and sequences to better itself in the future. Smart technology within these adaptive building envelope systems includes “real-time sensing, kinetic climate-adaptive components, smart materials, automation and the occupant ability to make adjustment.” 3 They are systems that work together to render the building more efficient and provide comfort for its occupants. These systems are superior to intelligent building skins as they intertwine with other electronic and mechanical systems making them perform at a high efficiency level all while ensuring long-term improvement and adaptability, something intelligent building skins lack. We see the birth of not only a material or assembly but a marriage between science and technology as these systems have: “encapsulated computing system that is situated in some environment and is capable of flexible, autonomous actions in order to meet its design objectives (…) takes sensory input from the environment and produces output actions that affect it. (…) [This system only gets more powerful and smarter over time as it] provides a steady and reliable responsive system. (…) 6

Responsive facade system

“A building exterior that can change in response to its surrounding environment to maximise its performance” – Design Buildings UK 5

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 10

The Al Bahar Tower present a perfect case study as the building constraints and conditions are very stringent. The blazing heat in the Abu Dhabi desert presents a huge problem as interior solar heat gain and glare will inevitably cause issues and compromise occupant comfort. Therefore, designers must come up with solutions that are cost effective and do not compromise the desired aesthetic. The answer is a responsive façade system made from 2 098 coated fiberglass shading panels strategically spread across the facade of the two 145-meter towers. “The geometry of the shading screen folds and unfolds in response to the movement of the sun, reducing solar gain by up to 50%, whilst simultaneously improving admission of natural diffused light into the towers and improving visibility.”7 While providing a solution to control solar glare and heat gain inside the building, these high-tech panels also have structural characteristics. As sand is omnipresent in locations such as Abu Dhabi, these panels serve as deflecting shields that protect the building from sandstorms that would normally compromise the structural integrity of the towers. These panels act as a curtain wall and sit approximately 2 meters away from the building face. They work in unison as one element as they track and follow the suns path and react (opening and closing) accordingly. During the night, these panels close as designers wanted to show off the building facade with lights. The next morning, during sunrise,

CASE STUDY #1

Al Bahar Towers

Location: Abu Dhabi,UAE Architect: AHR (Aedas)

Completion Date: June 2012 Building Type: Office Building

Adaptive System Responsive Facade System

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 11

the curtain wall of panels will adapt to the intensity and direction of the sun, repeating this process over and over.

As well as structural and functional properties, these panels allow the use of a wider variety of material options for architects. For example, the panels allow for the use of naturally tinted glass which lets in a larger quantity of light and provides better panoramic views for occupants. All this while reducing the need for artificial light sources which saves on electrical bills.

FUN FACT

“For the project’s sustainable

engineering and sensitive cultural and

urban approach, the towers were

awarded the 2012 Tall Building

Innovation Award by the Council of

Tall Buildings and Urban Habitat.”3

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 12

The Media-ICT building in Barcelona, Spain uses a smart material to improve its efficiency and occupant comfort levels. The south-east facade is covered in a cladding system made up of a polymer Ethylene tetrafluoroethylene (ETFE) cladding which serves as a thermal insulator, shading device, and solar filter. Three layers of plastic are stretched across one triangular metal frame while creating bubbles that fill the entirety of the south-east wall which receives 6 hours of sunlight a day. This system replaces traditional glass and hard plastic as building envelopes. This ingenuity behind this marvelous product is quite simple. It uses ETFE polymer that uses pneumatic mechanisms to inflate the interior layers and is automatically triggered by light sensors. As the first layer of plastic inflates it creates a cloud-like bubble that is used as a thermal barrier to keep heat out of the building. Furthermore, the other two layers change from

CASE STUDY #2

Barcelona Media-ICT Building

Completion Date: 2011 Building Type: Cultural Center

Location: Barcelona Architect: Enric Ruiz Geli

Adaptive System

Smart Material

GLASS VS. ETFE

“In comparison to glass, ETFE (1)

permit more sunlight; (2) greater

insulation; (3) costs 24 percent to 70

percent less to construct; (4) weigh

1/100 the weight of glass; and (5) has

characteristics that makes it more

flexible as a construction material.”3

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 13

translucent to opaque depending on the expansion or contraction of the ETFE polymer turning the building’s facade into a large shading device controlling and regulating the amount of sunlight that enters the building. One main distinction with this system is unlike the adaptive system on Al Bahar towers, this one does allow for adjustments within the system by the user. In other words, they are long term investments that require little to no maintenance and have long life spans. In summary, after extensive research on adaptive building envelope systems, we have concluded that they are more efficient and will be the future of building envelopes. As there are many varieties of systems out there composed of different assemblies, it is important to note that on a grand scale they are favorable however we do understand that some might be less economical and have greater environmental impacts as they use materials that do not conform to green building practices. These adaptive building envelope systems provide functional, economical, and aesthetic advantages for designers to create and think outside the box on how to improve and maintain occupant comfort within our building in the future. Like any new technology, the barrier to entry and the emergence of experimental products will always be high at the beginning. However, it is important to not shy away from these new possibilities as they present more energy efficient options that outperform their predecessors. “Tried and true” methods are being proven to be inefficient and outdated more and more as we see technological advancements and manufacturing costs being reduced. We, as designers and builders, have a role and responsibility to ensure safety all while providing spaces for people to gather and enjoy life. It is important to question traditional practices and improve on building methods for the future of our planet and the health of its occupants.

CONCLUSION

ADAPTIVE BUILDING ENVELOPE SYSTEMS

PAGE 14

1 https://archive.curbed.com/2019/9/19/20874234/buildings-carbon-emissions-climate-change 2 https://publications.lib.chalmers.se/records/fulltext/214574/214574.pdf 3 https://www.sciencedirect.com/science/article/pii/S1110016818302230 4 https://news.usc.edu/27789/it-s-the-smart-thing-to-do/ 5 https://www.designingbuildings.co.uk/wiki/Dynamic_fa%C3%A7ade 6 http://papers.cumincad.org/data/works/att/caadria2013_217.content.pdf 7 https://www.ahr-global.com/Al-Bahr-Towers

WORKS CITED