Master's Thesis : Sustainable facade design

Master’s Thesis July 2018 Written By Moemen Omara Thesis Advisor Prof. Enric Llorach Under Supervision of Prof. Eduard Bru / Prof. Aquiles Gonzalez

Universitat Politecnica de Catalunya Escola tècnica superior d'arquitectura

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UNIVERSITAT POLITECNICA DE CATALUNYA [UPC] ESCOLA TÈCNICA SUPERIOR D'ARQUITECTURA [ETSAB] CONTEMPORARY PROJECT PROGRAM MASTER'S THESIS FIRST PUBLISHED ON JULY 2018 BARCELONA, SPAIN

BY MOEMEN OMARA EMAIL: MOAMEN333@YAHOO.COM ALL RIGHTS RESERVED. THIS BOOK OR ANY PORTION MAY NOT BE REPRODUCED OR USED IN ANY MANNER WITHOUT THE EXPRESS WRITTEN PERMISSION OF THE PUBLISHER EXCEPT FOR THE USE OF BRIEF QUOTATIONS IN A BOOK REVIEW. PRINTED IN BARCELONA, SPAIN

BY MOEMEN OMARA 2018 © COPYRIGHT

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Sustainable façade design in Eixample : A Barcelona case

ACKNOWLEDGMENTS

I would first like to thank my thesis advisor Prof. Enric Llorah of ETSAB, Universitat Politecnica de Catalunya [UPC].And under the supervision of Prof. Eduard Bru and Prof. Aquiles Gonzalez. They helped me with the great knowledge they have got and their continuous guidance steered me in the right the direction whenever they thought I needed it.

I would also like to thank my great friends and colleagues that I was honored to have them during my master’s thesis studies in Universitat Politecnica de Catalunya .They made the period of my stay in Barcelona remarkable and we shared together a lot of knowledge and experience which added more value to my research. At the same time, I have to mention my dear friends of Cairo, Egypt for their continuous support wherever I am.

Finally, I must express my very profound gratitude to my parents [Emad Emara, Dalia ElZemeity, Omar Emara] for providing me with support and continuous encouragement throughout my period of study and through the process of researching and writing this thesis.

This accomplishment would not have been possible without everyone mentioned above.

Thank you,

Moemen Omara

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Sustainable faรงade design in Eixample : A Barcelona case

INDEX Abstract

07

Chapter 1 : Eixample District

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1. Introduction : Overview and History 2. Cerda Block 2.1 Ildefons Cerda 2.2 Cerda block design 2.3 The Evolution of Cerda blocks 2.4 Cerda blocks typologies and drawings 2.5 Cerda blocks Sustainability potentials 3. Understanding the Facades of Eixample 3.1 Street view façade 3.2 Courtyard façade 4. Case Studies : Selected projects in Barcelona Chapter 2 : Sustainable Façade design strategies

09 13 14 16 18 21 25 29 33 45

1. Sustainable facade introduction 2. Passive Solar Design Strategies 2.1 Heating 2.2 Cooling 3. Façade Elements 3.1 Glazing 3.2 Shading devices 3.3 Photovoltaics

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Chapter 3 : Sustainable Façade design Project

67

1. Project Introduction 1.1 Site Selection - Paula Montal Block 1.2 Paula Montal block Energy Performance 2. Project design 2.1 Design concept and analysis 2.2 Traditional Façade 2.3 Sustainable Façade design

46 55 57 62 65

67 68 69 71 79 83

Conclusion

97

Bibliography

98

List of Figures

99

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ABSTRACT

The design of a Contemporary building Façade is a reflection to the surrounding environmental and spatial conditions. As well as following the regulations and design style of a city or a district. One of these cases are the Cerda blocks in Eixample district, Barcelona .Cerda Blocks are one of the hugest modular urban projects in the world. It has faced a lot of progress in terms of form and shape throughout the years in reflect to the evolution in population and design strategies. But at the our current time Sustainability is the approach that the world need in terms of improving quality of life for residents and decreasing the energy demand. One of the main elements to achieve sustainability of building is its façade.

This thesis aims to design a Contemporary Sustainable façade in Eixample district of Barcelona in terms of getting advantage of the environmental and spatial conditions to generate power and save energy consumption .Applying this approach on 520 Eixmaple’s Cerda blocks through renovation or new construction will result in huge drop in Barcelona’s Energy consumption.

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Sustainable façade design in Eixample : A Barcelona case

The design of the façade comes after studying and analyzing the facades of Eixample district in terms of environmental impact, elements and materials. The target of the sustainable facade design is to get the advantage of solar energy to generate power, maximize use of natural light, improve natural ventilation, conduct and store heat in the space reducing heating energy. In addition to these aspects is following the regulations and design style in a historic district like Eixmaple.

“Facades must solve many tasks at once. Not only do they give buildings a face and character, they must assert themselves in the cityscape and fit into the surroundings.

They keep out rain, wind and cold, while protecting against heat and direct sun. The outer shell is also decisive for interiors. It contributes to a pleasant indoor climate, directs our gaze outwards through its openings, controls the entry of natural light, and contributes to our well-ventilated wellbeing with a balcony, terrace or loggia” Sandra Hofmeister, 2018

Figure 1 Eixample Facades, Javier castilla, catalogación y levantamiento gráfico de fachadas de las manzanas del eixample,upc

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CHAPTER 1

EIXAMPLE DISTRICT

1. Introduction: Overview and History The modern Barcelona was born in the Eixample, designed by the famous urban planner Ildefons CerdĂ who owes its unique and magical drawings .The district is defined as the engine of contemporary Catalonia and breaks down with the medieval past demolishing the walls.The Eixample was built in the years of industrialization of Catalonia, in the late nineteenth and early twentieth centuries.

Figure 2 Eixample District Aerial view , Gelio , www.Gelio.livejournal.com,2014

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Sustainable façade design in Eixample : A Barcelona case

The district cover an area of 7.48 km2 with a population of 266.416 (January 2017, Departament d'Estadística i Difusió de Dades. Ajuntament de Barcelona).

The number of Cerda blocks enclosed in Eixample district is around 520 blocks.

Eixample is the district that concentrates the highest number of inhabitants of the city, 16.4% of the population of Barcelona, with a density above the average.

It is one of the districts of the city that is more conditioned by the urban mobility. The daily circulation of vehicles through its streets demonstrates its role in the transversal connection of the city, to the detriment of the quality of life of its inhabitants in terms of health and habitability.

Density of population: 711 hab./ha (data of 2016) Green spaces by inhabitant: 1.9 m 2 per inhabitant (data of 2015) Area of areas with pedestrian priority: 7.8 ha (data of 2015) (Source: Ajuntament de Barcelona) There are six administrative neighborhoods: L'Antiga Esquerra de l'Eixample La Nova Esquerra de l'Eixample Dreta de l'Eixample Fort Pienc Sagrada Família Sant Antoni

Figure 3 Administrative neighborhoods of Eixample , Cerda”urbs I territory”,una visio de future.

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2.1 ILDEFONS CERDÀ

Cerdà was born in Centelles, Catalonia, Spain, in 1815. He originally trained as a civil engineer at the Escuela de Ingenieros de Caminos, Canales y Puertos, in Madrid. He joined the Corps of Engineers and lived in various cities in Spain before settling in Barcelona in 1848 .Cerdà became interested in politics and the study of urban planning.

When the government of the time finally gave in to public pressure and allowed Barcelona's city walls to be torn down, he realized the need to plan the city's expansion so that the new extension would become an efficient and livable place, unlike the congested old town within the walls. When he failed to find suitable reference works, he undertook the task of writing one from scratch while designing what he called the Ensanche or Eixample, borrowing a few technological ideas from his contemporaries to create a unique, thoroughly modern integrated concept that was carefully considered rather than whimsically designed1.

Figure 4 Ildefons Cerdà ,www.Ub.edu

Source : Wikipedia, Ildefons Cerdà, https://en.wikipedia.org/wiki/Ildefons_Cerd%C3%A0

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Sustainable façade design in Eixample : A Barcelona case

2.2 CERDA BLOCKS

The Ajuntament (Council) held a competition for projects in 1859. They actually preferred one by Antoni Rovira i Trias, for long straight streets radiating out fan-like from Plaça Catalunya. For reasons that have never been explained, orders came from Madrid that the plan to be adopted was that of another Catalan engineer, Ildefons Cerdà .(1815-1875) The Ajuntament had disliked Cerdà's scheme because it ignored the old centre of the city.

Cerdà had surveyed and drawn the city's first accurate plans in 1855. He was also influenced by the problems of El Raval, concerned with the cramped and unhealthy conditions of workers' housing and the high death rate and crime that he saw resulted from this.

Cerdà loved straight lines, and his idea was to place two of the Eixample's main avenues along a geographic parallel split by roads crossing perpendicularly. His central aim was to overcome social problems by using quadrangular blocks of a standard size, with strict building controls to ensure that they were built up on only two sides, to a limited height, leaving a shady square or garden in between. This recreational open space with open sides to the blocks was to guarantee the houses the maximum amount of sun, light and ventilation.

Figure 5 Cerda plan dimensions , http://www.fespm.es/CIUDAD/ciudad_ortogonal.htm

The sides of the blocks measured 113.3 metres and covered 12,370 square metres, of which at least 800 square metres were to be gardens. The regular streets were built 20 metres wide. Gran Via was 50 metres wide and Passeig de Gracia was as much as 60 metres wide. For Cerdà ,the function of the street was for communication and the movement of traffic.

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The most characteristic feature of Cerdà's plan is the 45º angled corner of each block .The idea behind this was to ensure more fluid traffic in all directions, above all for public transport: it was mainly the steam tram that Cerdà had in mind, and it was its long turning radius which determined the angle of the corners of the buildings.

Figure 6 Eixample’s Cerda Block Top View , L'Eixample i els interiors d'illa, Enric Pericas

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Sustainable façade design in Eixample : A Barcelona case

2.3 THE EVOLUTION OF CERDA BLOCKS The plan of Cerda block has faced many levels of development through time due to the increase in the population and the economic need of the residents of Barcelona.

Economic pressures persuaded public officials to loosen the regulations on public space encroaching into the green-space until public access was no longer possible.

The infilling of Cerda’s block increased from 67,200 square meters in the Plan Cerda in 1959 to nearly 295,000 square meters in 1972.

Figure 7 Cerda Block Evolution, Cerda and the Barcelona of the future (reality versus project), Joan Busquets, 2010

Despite the huge changes in regulations and laws but the facades of the Eixample are built and renovated in the same style and same proportions. On the other hand, inner courtyard facades weren’t given much importance as they were enclosed only for public users. In addition the a great variations in the heights of buildings that was generated due to continuous change in laws and regulations which affected the solar exposure of lower floor levels of the buildings in the block.

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The Evolution of the Eixample by law

1859 – Ground + 3 Floors (Max Height 16m) 1860 – Ground + Mezzanine + 5 floors (Max Height 20.5m) o Maximum Built Depth is 28m 1991 – Ground + Mezzanine + 5 floors + 1 Pent House (Max Height 20.5m) o Use of Inner court and extra inner Terrace 1932 – Ground + Mezzanine + 6 floors + 2 Pent House (Max Height 23.5m) o Use of Inner court basement and extra outer Terrace 1976 (Recovery Period) – Ground + Mezzanine + 5 Floors + 2 Basements (Max Height 20.5m) o Use of Inner court 2nd Basement and Cancelation of outer terrace o Party wall design, where two adjacent building share the same wall.2

Figure 8 Current Eixample Building Regulations

The 520 Cerda square blocks or 'manzanas' went up to much more than the planned heights, and in practice all the blocks have been enclosed, with very few inner gardens surviving. Today, most of the inner courtyards are occupied by car parks, workshops and shopping centres.

While Cerdà's more visionary ideas were largely lost over time, the construction of the Eixample did see the development of a specific type of building: the quality apartment block, with large flats on the lower Principal floor, often with glassed-in galleries for the drawing-room. The top floors contained apartments with roof gardens.

Source: La Rehabilitacio De L’Example , Ajuntament de Barcelona (1991)

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Sustainable façade design in Eixample : A Barcelona case

2.4 Cerda Blocks Typologies and Drawings

Figure 9 Block Candida Perez , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991)

Figure 10 Block de Les Aigues , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991)

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Figure 11 Block typologies , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991)

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Sustainable façade design in Eixample : A Barcelona case

Figure 12 Eixample Height variation , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991)

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2.5 Cerda Sustainability potentials Cerda blocks have been design to have the maximum solar energy through its orientation and it maximum built height. But through time this potential wasnot used so the buildings in the blocks were consuming energy having a negative impact instead of getting the positive advantages of sun exposure of the facades.

Barcelona’s Eixample can be considered the largest solar-planned neighbourhood in existence. Moreover, its history exemplifies the tension between solar access and developmental needs.

Figure 13 Cerda block solar Axis And Sun angle

CerdĂ intended to maximize solar access (and ventilation) to every apartment in four ways. Firstly, he limited building height to 16 metres ,for streets 20 metres wide. In addition , all blocks were oriented on NW-SE axis for maximize sun exposure time through out the day. Furthermore, he mandated that city blocks could only be built up on two instead of four sides, either parallel to each other or in the form of an L . This enabled the creation of large interior spaces and introduced sunlight and fresh air at both sides of each building.

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Sustainable façade design in Eixample : A Barcelona case

The buildings were supposed to be as tall as 16 meters in height as to not block the sunlight for other buildings.Originally, buildings were supposed to be constructed until the height of the yellow square as shown above. The sunlight would be penetrate all the buildings, including the bottom floor.

In addition all city blocks have chamfered corners, further improving solar access.

Lastly, he decided not to lay the street grid on the cardinal points, but diagonal to it.

Which gave all apartments access to sunlight during the day, while offering all streets shadow throughout the day.

Figure 14 Shadows on different street width , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991)

Only the chamfered corners and the orientation of the streets survived one hundred and fifty years of history. CerdĂ 's plan received much criticism at the time. The main reproach was that the design wasted too much valuable building space and thus money.

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Figure 15 Cerda block comparison between North-South and Northwest-southwest axis

You can see rotated blocks (NW-SE) on the right side get more sunlight than on the left-hand images, where the intersections lie north-south.The benefits earned in the winter are more light for daily activities and insulation of buildings, which means energy savings. In the summer, shadows are cast into all the streets, cooling down the city.3 The grid layout best suited for both maximum solar access and maximum building density is one with rectangular blocks running long in the east-west direction.

The buildings are faced in a way to get excellent exposure from of the sun. Below, the images in the two columns on the right represent street intersections in the winter and summer and how the sun hits the buildings.

Source: Kris De Decker, Lowtec magazine (2012), http://www.lowtechmagazine.com/2012/03/solar-oriented-cities-2solar-access-in-19th-century-cities.html

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Sustainable faรงade design in Eixample : A Barcelona case

Figure 16 La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991)

Figure 17 La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991)

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3. Understanding the Facades of Eixample The Eixample District has the unique Cerda’s urban plan and in the same manner it has a unique façade designs.And due to each Cerda block is divided into smaller adjacent land plots so most of the buildings in Eixample have party walls thus has just two facades :The Street view façade and Inner courtyard façade.

3.1 Street View Façade

The Eixample’s street facades are characterized by a modernism style with vertically proportioned balconies that are typically around 250mm height and 140mm width .The cladding and decorations differs from one building to another varying from normal plaster to luxury stone decorative cladding.

Figure 18 Sant Antoni Maria Claret, 30 . Jordi Sagalés Architects

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Sustainable façade design in Eixample : A Barcelona case

Balconies are the most important unit in an Eixample faรงade design, despite they not used often by users due to noise in the street side or sometimes lack of privacy. The balconies are very simple, with wrought iron railings little worked and some vegetation in most of time. The glass panels of balconies allow natural light most of the day with traditional wooden panels to control light interference.

The facades are also characterized by Grid and repetition. The Grids are one of the most commonly applied devices in international modern architecture .it provides organizing and ordering of the structure. The grid could be perpendicular, inclined or radial. Using this power of repetition gives the faรงade its own identity.

Figure 19 Eixample Street facades, Pin interest, https://www.pinterest.es/pin/519391769502720498/

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Figure 20 Street facades of Blames and Mallorca street

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Figure 21 Street facades of Valencia and Granados street

Source: Catalogación Y Levantamiento De Una Manzana Del Ensanche, José Juan Gómez Ramírez, Upc (2010)

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Sustainable façade design in Eixample : A Barcelona case

Figure 22 Street facades of Valencia and Balmes street

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Figure 23 Street facades of Granados and Mallorca street

Source: Catalogación Y Levantamiento De Una Manzana Del Ensanche, José Juan Gómez Ramírez, Upc (2010)

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3.2 Courtyard Façade

The Inner courtyard façade in the Cerda block has a great importance although its not used in the right manner .By analyzing and getting through current situation we may find some differences between each façade and the other where each façade has its own design , materials and shading devices .The current situation makes it a great priority to achieve a contemporary sustainable façade that get use of the great advantages of the inner facade in terms of collecting energy from the solar energy as well as passive strategies for ventilation , cooling and heating as well as getting use of the maximum possible natural light to reduce the Energy consumption in the indoors.

Figure 24 Eixample's courtyard Facade,L'Eixample i els interiors d'illa, Enric Pericas

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Sustainable façade design in Eixample : A Barcelona case

Figure 25 La Casa por el Tejado, Miba Arquitects, Joan ArtĂŠs

Figure 26 Eixample's courtyard Facade,L'Eixample i els interiors d'illa, Enric Pericas

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Courtyard Faรงade Analysis

A. Layers

The Gallery is a main feature of the inner courtyard faรงade, it consists of different layers which need to be improved in terms of their efficiency and performance. A single glazed windows acts as solar collector getting heat into the inner space which is absorbed and stored in a thick thermal mass wall that has some openings. This stored heat is released at night in winter time to keep the indoor warm. But the contrary happens in summer, Excessive heat is absorbed in the space which needs shading and cooling equipments which consumes energy instead of getting advantage of this solar exposure.

1- Thermal Mass wall 2- Single Glass panels 3- Roller Shading device 4- Iron Handrail

Figure 27 Eixample courtyard facade analysis

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Sustainable faรงade design in Eixample : A Barcelona case

B. Passive design strategy

The gallery of the back faรงade implements a passive solar design strategy where it works as a sun room employing a combination of direct gain and indirect gain system features. Sunlight entering the sunroom is retained in the thermal mass and air of the room. Sunlight is brought into the house by means of conduction through a shared mass wall in the rear of the sunroom, or by openings that permit the air between the sunroom and living space to be exchanged by convection.

Figure 28 Day and Night Operation of a Sunroom Isolated Gain System

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4. Case Studies 1. Low Energy MZ House

Architect: Calderon Folch Studio Location: Barcelona, Spain Year finished: 2012 Type: Residential

Figure 29 Energy consumption comparison, Calderon Folch studio webiste

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Sustainable faรงade design in Eixample : A Barcelona case

First Spanish Rehabilitated Building with a Passive House Standard.

A centenary house with the maximum comfort and minimum energy cost The challenge was to refurbish a house built in 1918 maintaining both the original volume and facade whilst improving the thermal and acoustic comfort.

The construction systems and materials used have made possible not only to achieve the goal but also to lower the energy demand from 171 kWh/m2 to 17 kWh/m2 annual.Its Considered“ One of the Most Remarkable Energy Efficiency Renovation Projects in Europe ,2013 �by Isover

Figure 30 MZ house's facade, Arch daily,2012.www.archdaily.com

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2. Edificio de Viviendas ,CASP 74 Architect: Bach Architects Location: Barcelona, Spain Year finished: 2009 Area : 3965.95 m2 Type: Residential

Figure 31 Street view facade, Jose Hevia, Arch daily (2013)

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Sustainable faรงade design in Eixample : A Barcelona case

Designing a residential building in the middle of the Eixample de Barcelona 150 years after the implementation of the Cerdรก Plan requires an extreme reflection on those aspects of the project that most move away from the Eixample stereotype. Among them, and one of the most relevant, is the function and the role of the faรงade, since the trace of changes in society.

Figure 32 Courtyard facade, Jose Hevia, Arch daily (2013)

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On the roof of the building, solar collectors for hot sanitary water are installed, connected to the air conditioning system of homes to reduce energy consumption. This fact, combined with the cross ventilation of all the houses through generous interior patios and the passive solar protection that composes the facades, makes the building work with a minimum contribution of the active means of air conditioning.

Figure 33 Interior of the gallery, Jose Hevia, Arch daily

All this, without renouncing subtle formal contributions. As an example, in some cases, the levitation of the mesh that composes all the ground floors in the main faรงade, on the ground floor, separated from the attics by the glazing, or its extension towards both medians by "disappearance" of the gables ; and in others, as in the rear faรงade, the idea of completing the landscape of galleries of a relatively well-preserved apple interior. In both facades it is a matter of reinterpreting the balcony, the booklet blinds, the imposts and the cornices to achieve a building that is integrated into the landscape built with a clearly contemporary language.6 Source: Edificio de Viviendas, Bach architects(2013), https://www.plataformaarquitectura.cl/cl/02-231232/edificio-deviviendas-casp-74-bach-arquitectes/5105fe90b3fc4b7992000331-apartment-building-casp-74-bach-arquitectes-photo

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Sustainable faรงade design in Eixample : A Barcelona case

Adapting the facade to new needs and maintaining respect and dialogue with so many years of history has been the will to project the Casp 74 building; using a contemporary language that interprets some of the solutions of the prototypical facades of Eixample (underlying idea in the regulations).

Figure 34 Street Faรงade Elevation, Bach architects (2013)

The program of the building consists of 27 homes distributed in PB + 5, and two commercial premises with loft facing Casp Street. The type floor houses five houses of one and two bedrooms, and the upper floor two houses of two rooms and two of a room, while on the ground floor, three duplex houses with their own garden are distributed in the interior facade of the block, time that two stores face the street. The facade to the street is solved through fixed panels formed by special pieces of stoneware in a vertical position framed by a thin steel frame, as well as aluminum sliding shutters that give the privacy and light control necessary to their large glazed sheets. The facade of the courtyard of the block is resolved with a steel grid that frames the large windows of the houses. Sun protection and privacy are resolved here with retractable lacquered aluminum blinds that will create a changing faรงade moving from the outside.

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3. Edificio Balmes

Architect: Carlos Ferrater Location: Carrer de Balmes ,145 (Barcelona, Spain) Year finished: 2003 Type: Offices (OAB , office of architecture in Barcelona)

Figure 35 Edificio Balmes street facade, Technal

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Sustainable faรงade design in Eixample : A Barcelona case

This mixed-use building connects with the historic architecture of the Eixample, maintaining the balance of hollows and massifs and using materials similar to the surrounding facades. In the flat faรงade the dynamism is given by the superposition of fixed and mobile layers, which contrast with the transparency of the ground floor.

The system developed by Technal (Barcelona based office) allows to create a faรงade formed by superimposed layers that can be added at any time, without the need to demolish the pre-existing structures. Therefore, in rehabilitation projects, the exterior image of a building could be updated or the acoustic performance of a facade exposed to an increase in external noise could be improved.

Figure 36 Edificio Balme Facade louvers, Technal

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4. Balmes Office Building

Architect: Xmas Arquitectura Location: CARRER DE BALMES 112 (Barcelona, Spain) Year finished: 2011 Type: Offices

Figure 37 Office building Renovation , Calle de balmes , Barcelona , Xmas Arquitectura

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Sustainable faรงade design in Eixample : A Barcelona case

Total emptying of the building while preserving the cataloged faรงade for its later rehabilitation. Building construction adapted to new technologies and needs.

Lighting of the facade with LED RGB luminaires creating decorative effects and different sequences in the balconies of the building. In addition to Recovery of the original coating of the facade.

Figure 38 Street Facade rennovation , Calle de balmes , Barcelona , Xmas Arquitectura

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5. Hotel OMM Barcelona Architect: Capella GarcĂ­a Arquitectura Location: Barcelona, Spain Year finished: 2003 Type: Hotel

Figure 39 Hotel OMM Barcelona , Javier (2010) , https://www.flickr.com/photos/javier1949/5015380521/in/photostream/

The building was created by the architect Juli Capella to integrate with a contemporary personality in the widening of Barcelona. The facade is characterized by gaps that open on the skin of the building in a totally unexpected way, as if it were a living surface that instinctively seeks sunlight. Such composition responds, in addition to an aesthetic concept, to the demanding functional program of an avant-garde urban hotel that proposes to combine large openings, natural light and pleasant views, with the timely privacy of its guests, in addition to guaranteeing maximum comfort through a correct soundproofing.

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Sustainable façade design in Eixample : A Barcelona case

The facade is resolved with a double skin: the exterior determines the image of the building using white limestone supported by a hidden structure of steel anchored in the floors;The interior ensures insulation through a hollow brick wall coated with projected polyurethane foam.

Figure 40 Hotel OMM Facade Skin, Javier (2010) , https://www.flickr.com/photos/javier1949/5015380521/in/photostream/

The practicable solution, using aluminum profiles with breakage of the thermal bridge and a double glazing of 6/8/5 + 4 mm, was preferable to the initial approach based on sliding to ensure a greater sound reduction and thus neutralize outside noise.7

Source: Hotel Omm, Technal website, https://www.technal.com/es/es/profesional/Descripcionreferencias/Hoteles/Hotel-OMM/

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CHAPTER 2

SUSTAINABLE FAÇADE DESIGN STRATEGIES

1. Introduction

The design of a sustainable façade aims to decrease the Energy demand of building and improve the quality of the indoor and outdoor environment through selecting appropriate materials and façade elements that could go along with applying passive design strategies.

In this chapter we will get close into façade design strategies, elements and materials that could naturally heat or cool the indoors without using artificial appliances and consumption of energy.

The continuous increase in energy consumption makes it a priority to go into sustainable design.In 2008, Barcelona energy consumption is distributed as follows: tertiary sector 29.9%, residential 27.9%, transports 24.1%, industry 17.2%.

Electricity is the primary energy consumption source and represents 44.3% of total.

The consumption ratio per inhabitant was 10.52 MWh/inhabit.

Since the end of 2004 to the end of 2008, solar photovoltaic (PV) capacity increased six fold to more than 16GW, wind power capacity increased 250% to 121GW and world‘s total power capacity from new renewables increased 75% to 250GW. Solar energy has been advocated for building applications for many years.

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Sustainable façade design in Eixample : A Barcelona case

2. Passive Solar design Passive solar design is one of several design approaches that when combined properly, these strategies can contribute to the heating, cooling, and daylighting of the indoors of buildings. In passive solar building design, windows, walls, and floors are made to collect, store, reflect, and distribute solar energy in the form of heat in the winter and reject solar heat in the summer.

The key to design a passive solar building is to design a façade that takes advantage of the local climate performing an accurate site analysis. Elements to be considered include window placement and size, and glazing type, thermal insulation, thermal mass, and shading devices.

The passive solar design is divided into passive solar heating which contributes in heating by storing heat gained from solar power or passive solar cooling through ventilation of the space.

A. Passive solar Heating

There are three approaches to passive systems: direct gain, indirect gain, and isolated gain. The goal of all passive solar heating systems is to capture the sun’s heat within the building’s elements and release that heat during periods when the sun is not shining. At the same time that the building’s elements or materials is absorbing heat for later use, solar heat is available for keeping the space comfortable .

Design recommendations x x x

The building’s south face should receive sunlight between the hours of 9:00 A.M. and 3:00 P.M. (sun time) during the heating season.

Interior spaces requiring the most light and heating and cooling should be along the south face of the building. Less used spaces should be located on the north.

Elements to help control under and overheating of a passive solar heating system include shading devices and roof overhangs.8

Source: Whole building design guide, National Institute of building science (2016), https://www.wbdg.org/resources/passive-solar-heating

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1. Direct Gain

In this system, the actual living space is a solar collector, heat absorber and distribution system. South facing glass admits solar energy into the house where it strikes directly and indirectly thermal mass materials in the house such as masonry floors and walls.

The direct gain system will utilize 60 – 75% of the sun’s energy striking the windows.

Figure 41 Thermal mass in the interior absorbs the sunlight and radiates the heat at night.

In a direct gain system, the thermal mass floors and walls are functional parts of the house. The thermal mass will temper the intensity of the heat during the day by absorbing the heat. At night, the thermal mass radiates heat into the living space.

Design recommendations x x x x

Do not exceed 6 inches of thickness in thermal mass materials.

Use a medium dark color for masonry floors; use light colors for other lightweight walls; thermal mass walls can be any color.

The surface area of mass exposed to direct sunlight should be 9 times the area of the glazing.

Sun tempering is the use of direct gain without added thermal mass. For most homes, multiply the house square footage by 0.08 to determine the amount of south facing glass for sun tempering.9

Source: Passive Solar design, Sustainable sources website, http://passivesolar.sustainablesources.com/#guidelines

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Sustainable façade design in Eixample : A Barcelona case

2. Indirect Gain

In an indirect gain system, thermal mass is located between the sun and the living space. The thermal mass absorbs the sunlight that strikes it and transfers it to the living space by conduction. A main application on indirect gain system is Thermal storage wall systems (Trombe Walls) The indirect gain system will utilize 30 – 45% of the sun’s energy striking the glass adjoining the thermal mass.

Figure 42 Thermal Mass Wall or Trombe Wall Day and Night Operation

Thermal storage wall systems (Trombe Walls) The thermal mass is located immediately behind south facing glass in this system.

Operable vents at the top and bottom of a thermal storage wall permit heat convection between the wall and the glass into the living space. When the vents are closed at night radiant heat from the wall heats the living space.

Trombe wall is a system for indirect solar heat gain and it is a good example of thermal mass, solar gain, and glazing properties used together to achieve human comfort goals passively.It consists of a dark colored wall of high thermal mass facing the sun, with glazing spaced in front to leave a small air space. The glazing traps solar radiation like a small greenhouse.

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Trombe walls are a very useful passive heating system.They require little or no effort to operate, and are ideal for spaces where silence and privacy are desirable. A successful Trombe wall optimizes heat gain and minimizes heat loss during cold times, and avoids excess heat gain in hot times.

Figure 43 Trombe wall mechanism through day and night

Design recommendations

A typical Trombe wall consists of a 20 - 40cm thick masonry wall painted a dark, heat-absorbing color and faced with a single or double layer of glass.

The glass is placed between 2 – 15 cm away from the masonry wall to create a small airspace. Heat from sunlight passing through the glass is absorbed by the dark surface, stored in the wall, and conducted slowly through the masonry.

The glass prevents the escape of radiant heat from the warm surface of the storage wall. The heat radiated by the wall is therefore trapped within the air gap, further heating the wall surface.

For a 40cm thick Trombe wall, heat will take about 8 to 10 hours to reach the interior of the building. This means that the room behind remains comfortable through the day and receives slow heating for many hours after the sun sets.10

Source: Autodesk knowledge Network, Sustainability workshop, https://sustainabilityworkshop.autodesk.com/buildings/passive-heating

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Sustainable façade design in Eixample : A Barcelona case

Thermal mass

Its one of the most important elements to implement a passive solar design strategy .Its the ability of the Wall to absorb and store heat during the day and release it gradually during night. Without thermal mass, heat that has entered a space will simply re-radiate back out quickly, making the space overly hot with sunlight and overly cold without.

Design recommendations

Choose the right amount of mass. This is determined by how much heat energy the space requires .In general, comfort and performance increase with increase of thermal mass.

Large surface areas of thermal mass, with sufficient solar exposure. A rule of thumb is a mass surface-to-glass area ratio is 6:1.

In direct gain storage, thin mass is more effective than thick mass. The most effective thickness in masonry materials is the first 100mm. Thicknesses beyond 150mm are usually unhelpful as the heat is simply carried away from the surface and lost. The most effective thickness in wood is the first 25mm.

Insulating the thermal storage from exterior climate conditions, so that they do not add or remove too much heat.

It is important to locate as much thermal mass in direct sunlight as possible.

However, the mass that is located out of the direct sunlight .

Thermal mass storage is as much as four times more effective when the mass is both heated directly by the sun and is subject to convective heating from warmed air, compared to being only heated by convection.

Locating thermal mass in interior partitions is more effective than external walls.

Assuming they both have equal solar access, the internal wall heat will transfer heat out of both surfaces whereas the external wall will often lose half to the outside.

The most effective internal storage wall masses are those located between two direct gain spaces.

Thermal mass can be combined with glazing to form "Trombe walls".11

Source: Autodesk knowledge Network, Sustainability workshop, https://sustainabilityworkshop.autodesk.com/buildings/passive-heating

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Thermal mass - Drywall boards

Using a more technological thermal mass is by putting drywall boards in the sun exposed façade. The idea is that warmth from the sun during the day will be stored in the wallboard, and then released at night to keep the space warm. It will both help prevent overheating during the day and help reduce heating costs during the evening hours. In essence, it's a high-tech form of thermal-mass materials that are typically used in passive solar design Drywall boards (also known as gypsum boards) which use pure plaster, paraffin microcapsules constitute almost half of the plaster mixture used in the new boards.

When its exposed to sunlight ,the heat cause the temperature within a building to rise, that paraffin turns to a liquid state. In doing so, it absorbs some of the ambient heat, causing the building to cool down. that can reduce a building’s energy consumption by up to 40 percent.

Figure 44 Dry wall prototype, Universidad Politécnica de Madrid

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Sustainable façade design in Eixample : A Barcelona case

Phase change materials are a relatively new class of materials, which are used to add thermal mass without adding weight or bulk. They may replace standard wall board, or may be an additional layer in walls or floors. They are relatively rare but quickly increasing in popularity as technologies improve and prices drop.

These materials store heat by using the material's change of phase, usually from solid to liquid and back. It takes a large amount of heat to turn a solid into a liquid, or a liquid into a gas, even without changing the temperature. For instance, it requires 100 calories of energy to heat a gram of water from 0째C to 100째C; however, it takes 539 calories to turn a gram of water at 100째C into a gram of steam at 100째C. When the steam turns back into water, all that heat energy is released.

Because of the large amounts of energy needed for phase changes, these materials can radically increase their thermal mass without adding weight or size. For instance, a (1cm) thick sheet of phase-change drywall could have the thermal mass of several inches of concrete.

Figure 45 Phase changing materials cycle

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3. Isolated Gain

An isolated gain system has its integral parts separate from the main living area of a house. Examples are a sunroom. The ability to isolate the system from the primary living areas is the point of distinction for this type of system.

The isolated gain system will utilize 15 – 30% of the sunlight striking the glazing toward heating the adjoining living areas. Solar energy is also retained in the sunroom itself.

Sunrooms Sunrooms (or solar greenhouses) employ a combination of direct gain and indirect gain system features. Sunlight entering the sunroom is retained in the thermal mass and air of the room. Sunlight is brought into the house by means of conduction through a shared mass wall in the rear of the sunroom, or by vents that permit the air between the sunroom and living space to be exchanged by convection.

Figure 46 Day and Night Operation of a Sunroom Isolated Gain System

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Sustainable façade design in Eixample : A Barcelona case

Design recommendations

Use a dark color for the thermal wall in a sunspace.

The thickness of the thermal wall should be 8-12 inches for adobe or earth materials, 10-14 inches for brick, 12-18 inches for concrete.

Withdraw excess heat in the sunroom until the room reaches 45 degrees and put the excess heat into thermal mass materials in other parts of the house.

For a sunroom with a masonry thermal wall, use 0.30 square feet of south glazing for each square foot of living space floor area. If a water wall is used between the sunroom and living space instead of masonry, use 0.20 square feet of south facing glass for each square foot of living area.

Have a ventilation system for summer months.12

The sunroom has some advantages as an isolated gain approach in that it can provide additional usable space to the house and plants can be grown in it quite effectively.

Sunspaces are equally simple and silent, and can allow views. Rooms heated by a Trombe wall or sunspace often feel more comfortable than those heated by forced-air systems, even at lower air temperatures.

Figure 47 A Trombe wall (left) and attached sunspace (right)

Source: Passive Solar design, Sustainable sources website, http://passivesolar.sustainablesources.com/#guidelines

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B. Passive Solar Cooling A primary strategy for cooling buildings without mechanical assistance in hot humid climates is to employ natural ventilation.

1. Ventilation & Operable Windows A primary strategy for cooling buildings without mechanical assistance (passive cooling) in hot humid climates is to employ natural ventilation

2. Wing Walls Wing walls are vertical solid panels placed alongside of windows perpendicular to the wall on the windward side of the house. Wing walls will accelerate the natural wind speed due to pressure differences created by the wing wall.13

Figure 48 Top View of Wing Walls Airflow Pattern, House-energy.com

Source: Wing walls mechanism, House Energy website, http://www.house-energy.com/Cooling/VentilationBreezes.html

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Sustainable faรงade design in Eixample : A Barcelona case

3. Thermal Chimney

A thermal chimney employs convective currents to draw air out of a building. By creating a warm or hot zone with an exterior exhaust outlet, air can be drawn into the house ventilating the structure.

Thermal chimneys can be constructed in a narrow configuration with an easily heated black metal absorber on the inside behind a glazed front that can reach high temperatures and be insulated from the house. The chimney must terminate above the roof level. A rotating metal scoop at the top which opens opposite the wind will allow heated air to exhaust without being overcome by the prevailing wind.14

Figure 49 Thermal Chimney mechanism, bigladdersoftware.com

Source: Passive Solar design, Sustainable sources website, http://passivesolar.sustainablesources.com/#guidelines

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3. Faรงade Elements

3.1 Glazing The choice of glazing type in a faรงade is very critical decision that could help the faรงade to do its function and be adaptive to the surrounding environment .The great technology in that field made a variety that could help the architect to choose what is suitable to the faรงade strategy .Upon the U and G value you control insulation or heat transmittance .New types include noise reduction and solar control glass.

G value The g-value is a measure of how much solar heat (infrared radiation) is allowed in through a particular part of a building. A low g-value indicates that a window lets through a low percentage of the solar heat. The g-value can be improved by having the outer glass pane coated with an IR-reflecting surface which reflects some of the radiant heat. The aim of this is partly to reduce the costs of cooling the property, and partly to improve the indoor environment in properties without comfort cooling.

Untreated insulating glass has a g-value of approximately 1.3 U-value The U-value is a measure of how much heat escapes via the windows, walls and roof for example. The U-value is often measured for the whole window structure with the combination of glass, frame and sash. The lower the U-value, the better the insulating capacity of the window.

15

Source: Hammer Glass company, https://www.hammerglass.com/faq/u-value-g-value/

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Sustainable faรงade design in Eixample : A Barcelona case

Solar Control glass

Glass manages solar heat radiation by three mechanisms: reflectance, transmittance and absorptance.

These are defined as follows: 1. Reflectance – the proportion of solar radiation reflected back into the atmosphere 2. Direct transmittance – the proportion of solar radiation transmitted directly through the glass 3. Absorptance – the proportion of solar radiation absorbed by the glass.

Figure 50 Solar control glass , Pilkington

In hot conditions or for building with high internal loads, solar control glass is used to minimize solar heat gain. It allows sunlight to pass through a window or façade while radiating and reflecting away a large degree of the sun's heat.In more temperate conditions, it can be used to balance solar control with high levels of natural light.

Solar control glass is not necessarily colored or mirrored glass, although such finishes can be applied for aesthetic purposes if desired. It incorporates invisible layers of special materials on the glass which have the dual effect of allowing sunlight in, while repelling solar heat. Solar control glass units are typically double glazed, which means they also insulate well. 16

Source: Pilkington Glass industry, https://www.pilkington.com/en-gb/uk/architects/types-of-glass/solar-controlglass/how-it-works

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Noise reduction glass

Insulating building interiors against noise has now become a major design criterion, due to the rapid increase in road and air traffic and the development of the urban motorways.

Nosie reduction glass industry has developed in past year to provide more sound insulated indoor and one of its products is Pilkington Optiphon which is a high quality acoustic laminated glass that offers excellent noise reduction without compromising on light transmittance or impact performance.

Pilkington Optiphon offers the opportunity to achieve specific noise reduction requirements. Pilkington Optiphon can be combined with other Pilkington products for a multi-functional noise-reduction monolithic glass or a multi-functional noisereduction Insulating Glass Unit providing additional benefits, such as thermal insulation, solar control or self-cleaning.

Provides a range of noise control levels Can be combined with other products in the Pilkington to achieve other benefits Available in five standard thicknesses

Figure 51 Optiphop noise reduction glass

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17

Figure 52 Table of Nosie reduction glass products

Source: Pilkington Glass industry, http://www.pilkington.com/en-gb/uk/products/product-categories/noisecontrol/pilkington-optiphon#brochures

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Thermal Insulated Glass

Glass can also control heat access through indoor By replacing single glazed window glass with thermally insulated windows with a product like Pilkington energiKare double glazing units, the amount of energy lost can be reduced by up to 75% and heating bills can be lowered by up to 20% each year.

Thermal transmittance calculator: https://www.onyxsolar.com/u-termical

Figure 53 Upper floor shows thermally insulated glass while lower floor is normal

Figure 54 Table of solar glass products

Source: Pilkington Glass industry, http://www.pilkington.com/en-gb/uk/products/product-categories/thermalinsulation

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Sustainable faรงade design in Eixample : A Barcelona case

3.2 Shading devices

The shading devices are very important façade element to control the façade and its performance. Placing Horizontal or vertical louvers affect the heat gain, daylighting and glare. In addition it gives the user to control the privacy in the indoor space.

Advantages Louver windows provide free passage of air and sufficient light.

Louvers afford sufficient privacy and also provide protection against excessive daylight and glare inside buildings without in any way affecting ventilation.

Louver is energy efficient as it uses the natural ventilation to reduce your heating and cooling cost.

The design of effective shading devices will depend on the solar orientation of a particular building facade. For example, simple fixed overhangs are very effective at shading south-facing windows in the summer when sun angles are high. However, the same horizontal device is ineffective at blocking low afternoon sun from entering west-facing windows during peak heat gain periods in the summer.

A wide range of adjustable shading products is commercially available from canvas awnings to solar screens, roll-down blinds, shutters, and vertical louvers. 19

Figure 55 Plans and sections of shading devices

Source: Whole building design guide (2016), https://www.wbdg.org/resources/sun-control-and-shading-devices

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Vertical Operable Louvers

Figure 56 Vertical Louver , Locarno Louvers

Figure 57 Villa vertical louvers, Auckland, https://www.eboss.co.nz/library/locarno/operable-vertical-louvres

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Sustainable faรงade design in Eixample : A Barcelona case

Horizontal Operable Louvers

Figure 58 Horizontal Louvers, Locarno Louvers

Figure 59 Remuera House , Auckland,https://www.eboss.co.nz/library/locarno/operable-horizontal-louvres

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3.3 Photovoltaic Cells Building Integrated Photovoltaics

(BIPV) are photovoltaic materials Used to replace conventional building materials in parts of the building façades or skylight. PV panel is sandwiched between two thin

panels of glass which allows natural light interference in addition to collecting energy from solar power. They could also be adapted in size on the building.

The power generated from BIPV on a façade is nearly 25% power generated from a standard PV cells placed on roof.20 There are four main types of BIPV products

Crystalline silicon solar panels for ground-based and rooftop power plant

Amorphous crystalline silicon thin film solar pv modules which could be hollow, light, red blue yellow, as glass curtain wall and transparent skylight

CIGS-based (Copper Indium Gallium Selenide) thin film cells on flexible modules laminated to the building envelope element or the CIGS cells are mounted directly onto the building envelope substrate

Double glass solar panels with square cells inside.

BIPV Cells module60 Figure

Source: IEA ,International energy agency

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Sustainable façade design in Eixample : A Barcelona case

Photovoltaic Panels

Photovoltaic Panels are the most effective solutions to generate energy and its becoming widely used in all building parts not only the roof.so placing a panel on the faรงade would add extra energy to the building. PV panels comes in standard sizes which could be customized in some cases .The concept is that these dark crystalline silicon points are connected together through wires collecting energy all sun exposure time and transferring this energy to solar collector.

Average energy generation per 1 square meter is equal to 15 watts.21

Figure 61 Pv cells output Power calculations

Figure 62 PV Panel Module

Source: Pv cells Power calculations, https://www.onyxsolar.com/photovoltaic-estimation-tool

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CHAPTER 3

SUSTAINABLE FAÇADE DESIGN PROJECT

INTRODUCTION The project aims to Construct a Residential Building with a Sustainable Façade Design in a Cerda Block .The new design will be designed to acquire the maximum possible passive design strategies which will be integrated with Sustainable façade elements and plug-ins.In addition the new design will consider design style and regulations of Eixample district.

The target of the project to promote sustainable design approach in the element of the façade along with the plan of Barcelona Municipality which encourage user to construct or renovate with sustainable design that will lead to minimizing energy consumption.

Objectives : x x x x x

Not less than 80% reduction of the energy demand than similar land plots Improvement of the indoor and outdoor environment quality Increase of property value Achieve a contemporary façade design Reduction of Global warming and CO2 Emissions

The facade design comes after studying possible the site environmental and spatial conditions, passive design solutions, Sustainable façade elements and materials.in which all these aspects are integrated when designing the façade and getting the design into a cycle of optimization until reaching highest façade performance.

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Sustainable façade design in Eixample : A Barcelona case

1.1 SITE SELECTION The Eixample’s Cerda block gives the project a great advantage for being a prototype for sustainable facades in the whole district. All Cerda blocks have save orientation ,Same geometry but with quite differences in building heights due to change in the regulations through time. Further more, some of Blocks have inner courtyard garden and some has building. The site selected is an empty land plot in Paula Montal Block.

Figure 63 Paula Montal block Site Analysis

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1.2 Paula Montal block Energy Performance

An Energy Study was implemented on Paula Montal block to measure Energy consumption and solar energy generation possibilities of the Block by22(A. Behfar, M. M. Riyahi Alam, R. Shahmoradi, M. Tadi, S. Vahabzadeh, INTERNATIONAL JOURNAL of ENERGY and ENVIRONMENT)

Energy Consumption per block is 1900 MWH/YEAR Total energy production is 562.09 Energy Efficiency is 30%

Since blocks have the same dimensions and orientation, and also, the neighborhood is favoring a regular grid pattern all around it, therefore, a comprehensive solar access analysis on one of the blocks could be a reliable representation for the others. The solar radiation of the block was calculated to be 730 KWh/m2/year, which with a 15% efficient PV cell, it produces about 110 KWh/m2/year.

Figure 64 Solar average daily radiation in Wh/m2 of roof top and envelopes in the Paula Montal (south façades)

Source: Issue 2, Volume 7, 2013, Optimizing energy performance of a neighborhood via IMM® methodology: Case Study of Barcelona, A. Behfar, M. M. Riyahi Alam, R. Shahmoradi, M. Tadi, S. Vahabzadeh, INTERNATIONAL JOURNAL of ENERGY and ENVIRONMENT.

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Sustainable façade design in Eixample : A Barcelona case

Current studies indicate that the 30% up to 50% of energy consumption is covered by means of solar collectors and PV Panels and the local region temperature could be reduced by proposed vegetation which could further decrease buildings‘ cooling loads in summer and improve the thermal environment of the city at local scale.

It is obvious that roof top and upper levels of envelope receive more solar radiation than the lower levels. This amount varies between 1500 Wh/m2/day and 2400 Wh/m2/day on south facing envelopes and between 150 Wh/m2/day and 900 Wh/m2/day on north facing facades. Roof top shows the maximum solar radiation of more than 3500 Wh/m2/day and could be identified as the best surface for solar power installations.

It is true that roof top has the maximum incident radiation flux, but some potential areas on façade could also be identified which have high solar radiation. Depending on the desired efficiency for the whole block, this location proves suitable for electricity production of 22 MWh per year (110 KWh/m2/year * 200m2).23

Figure 65 Solar average daily radiation in Wh/m2 of roof top and envelopes in the Paula Montal (north façades)

Source: Issue 2, Volume 7, 2013, Optimizing energy performance of a neighborhood via IMM® methodology: Case Study of Barcelona, A. Behfar, M. M. Riyahi Alam, R. Shahmoradi, M. Tadi, S. Vahabzadeh, INTERNATIONAL JOURNAL of ENERGY and ENVIRONMENT.

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2.1 Design Concept The project aims to design a Contemporary sustainable façade responsive to surrounding environment and Following district style and regulations.

Design Methodology A. Site Analysis B. Ecotect analysis for street façade and courtyard facade C. Analysis of a traditional façade module D. Design optimization E. Designing Sustainable façade module F. Merging modules to generate a complete façade design

Site Analysis The Selected Land plot is situated in the center of Eixample district. In addition, the site gains huge importance because the new building will be the entrance to the inner court garden of Paula Montal block. So the new sustainable façade design will be the gate of the public to get into the garden increasing their awareness with sustainability approaches undertaken worldwide reduce energy consumption.

Figure 66 Paula Montal block site plan

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Figure 67 Selected land plot site plan

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Figure 68 Paula montal street faรงade

Figure 69 Paula montal Courtyard facade

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Sustainable faรงade design in Eixample : A Barcelona case

Figure 70 Paula Montal block street facades

Figure 71 Paula Montal block courtyard facades

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ECOTECT ANALYSIS Ecotect analysis of the block shows 50% of the faรงades has direct sun exposure throughout the day.

Figure 72 Facades which is not oriented on solar access

Figure 73 Facades which are oriented on solar access

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Sustainable faรงade design in Eixample : A Barcelona case

Figure 74 Facades which are oriented on solar access

Figure 75 Facades which are oriented on solar access

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DESIGN OPTIMIZATION To optimize the PV cells orientation and shading devices it’s essential to analyze sun angle in winter and summer, which will result in different setup for the fixtures.24 Winter analysis: 21st of December at 15:00

WINTER

Figure 76 Winter sun path analysis

Source: Sun Angle calculation, http://solarelectricityhandbook.com/solar-angle-calculator.html

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Sustainable façade design in Eixample : A Barcelona case

Ecotect analysis on the land plot shows the solar axis is facing the courtyard façade side so it’s obvious that the low angle of winter sun on the courtyard façade, while high angle during summer, which will affect our façade design strategy.

Summer analysis: 21st of June at 15:00

SUMMER

Figure 77 Summer sun path analysis

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2.2 TRADITIONAL EIXAMPLE FAÇADE STREET SIDE FAÇADE WINTER

Traditional street façade has balcony which is not used by users due to noise and lack of privacy.In addition they use wooden panels to control light interference through the interior space.

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Sustainable façade design in Eixample : A Barcelona case

SUMMER

In summer, the wooden panels are closed to keep out heat and allow some ventilation through the openings.

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2.2 TRADITIONAL EIXAMPLE FAÇADE COURTYARD FAÇADE WINTER

In winter, The gallery works as a sunspace collecting sun rays through the glass panels and storing it in the thick thermal mass wall during the day.At night this heat is released to the inner living space.

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SUMMER

In summer, The shading devices play important role to protect from sunrays and overheating through the space, with possibilities to tilt its angle for better shading and allowing air ventilation.

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2.3 SUSTAINABLE EIXAMPLE FAÇADE STREET SIDE FAÇADE

WINTER/SUMMER

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Sustainable façade design in Eixample : A Barcelona case

The new sustainable module works to give the users the ability to control natural light and ventilation through winter and summer through operable vents and louvers. The new design uses wing walls that maximize the ventilation coming from wind direction to the street faรงade. The design uses timber lovers and timber cladding which adds the value of using renewable resources.

VERTICAL LOUVERS

VENTIALTION INLETS

Wing wall accelerates the interference of natural ventilation from north direction through low height placed inlets and doing a circulation in the indoor then getting out through high placed openings.

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2.3 SUSTAINABLE EIXAMPLE FAÇADE COURTYARD FAÇADE WINTER

The new sustainable module of courtyard façade aims to collect solar energy through PV cells which are tilted to the sun angle. In addition, it consists of operable vertical louvers and solar control glass to generate an effective sunspace in the behind the glass. The heat collected in the sunspace is absorbed by thin thermal drywall boards.

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Sustainable façade design in Eixample : A Barcelona case

SUMMER

In summer, the louvers are closed to block sun heat .In addition, the PV cells are tilted to the high summer angle.as well as allowing ventilation from low inlets situated below the shaded PV cells.

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COURTYARD FAร ADE SECTION

WINTER

Winter sun

Rotating thermal mass wall

During winter the PV cells are tilted on an angle of 26 to allow more sun exposure. In addition, the drywall boards (thermal mass walls) are closed to make the sun space more effective.

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Sustainable faรงade design in Eixample : A Barcelona case

SUMMER

Summer sun

During summer the PV cells are tilted on an angle of 72 to allow more sun exposure and to act as an overhang to make shadows for lower levels. In addition, the drywall boards (thermal mass walls) are opened to add more space to the indoor area.

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STREET SIDE FAÇADE DESIGN TRADITIONAL FAÇADE

Combining the traditional modules creates a typical Eixample façade which lakes to the aspects that make a positive contribution on improving the residents’ indoor comfort and energy consumption in general.

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Sustainable façade design in Eixample : A Barcelona case

STREET SIDE FAÇADE DESIGN SUSTAINABLE FAÇADE

The new sustainable façade design which merges all effective ventilation strategies and operable louvers to control natural light with timber cladding all over the façade gives a new theme for the Paula Montal block. In addition to having a welcoming entrance to the garden in the center which attracts visitors and promoting sustainability goals.

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COURTYARD FAÇADE DESIGN TRADITIONAL FAÇADE

The traditional courtyard façade also doesn’t work on the most effective way to get advantage of the environmental conditions as well as it lakes to energy generation fixtures and plug-ins.

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Sustainable façade design in Eixample : A Barcelona case

COURTYARD FAÇADE DESIGN SUSTAINABLE FAÇADE

The new sustainable design of the courtyard façade maximized getting the advantage of the sun all over the day to heat the interior spaces through an improved sunspace as well as locating a movable PV cells to collect energy all over the year.

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CONCLUSION A building facade is not just a shell for a building, it’s the most important element that must be integrated with the surrounding context. So after applying analysis on the traditional facades of Eixample district many negative aspects were noticed concerning energy consumption, resident's comfort, natural heating and cooling.

These strategies ranging materials, passive design strategies and facade elements.

According to Eixample district’s design style of grid and repetition which consisted of a repeated facade module so the design methodology was to optimize this module to achieve a contemporary sustainable one. The new design achieves maximum use of natural ventilation, natural light, solar energy collection, passive heating, noise reduction and operable shading.

As a sequence, by applying the new sustainable module on the two facade sides of Eixample district ( street side and courtyard side ) and repeating it on the big number of Cerda blocks of Eixample which share nearly same conditions, we will achieve a huge drop in the energy use of Barcelona and improving the quality of living in the indoors. This strategy will go along with the vision of Barcelona Municipality to achieve a more sustainable city through grants they offer for building owners for using PV cells to generate energy or improving facade efficiency.

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BIBLIOGRAPHY

Francesc Magriya, Fernando Marza, 2009. Cerda 150 years of Modernity.

Barcelona: Fundacio Agbar.

Joan Busquets,Miquel Ayala, 2010. Cerdà and the Barcelona of the future: reality versus project. s.l.:Diputació de Barcelona.

Municipality, B., 1993. La rehabilitació de l'Eixample, 1987-1991. Barcelona: Regidoria d'Edicions i Publicacions.

Territorials, I. d., 1994. Cerdà, urbs i territori: una visio de future. Barcelona: Fundacio catalana per a la recerca.

Trubiano, F., 2013. Design and construction of high performance homes: building envelopes, renewable energies, and integrated practice. s.l.:Routledge.

Zhang, W., 2011. Sustainable renovation projects of residential buildings: 5 examples in Austria. s.l.: Chalmers tekniska högsk..

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LIST OF FIGURES Figure 1 Eixample Facades, Javier castilla, catalogación y levantamiento gráfico de fachadas de las manzanas del eixample,upc 8 Figure 2 Eixample District Aerial view , Gelio , www.Gelio.livejournal.com,2014 9 Figure 3 Administrative neighborhoods of Eixample , Cerda”urbs I territory”,una visio de future.

10 Figure 4 Ildefons Cerdà ,www.Ub.edu 13 Figure 5 Cerda plan dimensions , http://www.fespm.es/CIUDAD/ciudad_ortogonal.htm 14 Figure 6 Eixample’s Cerda Block Top View , L'Eixample i els interiors d'illa, Enric Pericas 15 Figure 7 Cerda Block Evolution, Cerda and the Barcelona of the future (reality versus project), Joan Busquets, 2010 16 Figure 8 Current Eixample Building Regulations 17 Figure 9 Block Candida Perez , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991) 18 Figure 10 Block de Les Aigues , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991) 18 Figure 11 Block typologies , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991) 19 Figure 12 Eixample Height variation , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991) 20 Figure 13 Cerda block solar Axis And Sun angle 21 Figure 14 Shadows on different street width , La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991) 22 Figure 15 Cerda block comparison between North-South and Northwest-southwest axis 23 Figure 16 La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991) 24 Figure 17 La Rehabilitacio De L’EIxample , Ajuntament de Barcelona (1991) 24 Figure 18 Sant Antoni Maria Claret, 30 . Jordi Sagalés Architects 25 Figure 19 Eixample Street facades, Pin interest, https://www.pinterest.es/pin/519391769502720498/ 26 Figure 20 Street facades of Blames and Mallorca street 27 Figure 21 Street facades of Valencia and Granados street 27 Figure 22 Street facades of Valencia and Balmes street 28 Figure 23 Street facades of Granados and Mallorca street 28 Figure 24 Eixample's courtyard Facade,L'Eixample i els interiors d'illa, Enric Pericas 29 Figure 25 La Casa por el Tejado, Miba Arquitects, Joan Artés 30 Figure 26 Eixample's courtyard Facade,L'Eixample i els interiors d'illa, Enric Pericas 30 Figure 27 Eixample courtyard facade analysis 31 Figure 28 Day and Night Operation of a Sunroom Isolated Gain System 32 Figure 29 Energy consumption comparison, Calderon Folch studio webiste 33 Figure 30 MZ house's facade, Arch daily,2012.www.archdaily.com 34 Figure 31 Street view facade, Jose Hevia, Arch daily (2013) 35 Figure 32 Courtyard facade, Jose Hevia, Arch daily (2013) 36 Figure 33 Interior of the gallery, Jose Hevia, Arch daily 37 Figure 34 Street Façade Elevation, Bach architects (2013) 38

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Sustainable façade design in Eixample : A Barcelona case

Figure 35 Edificio Balmes street facade, Technal 39 Figure 36 Edificio Balme Facade louvers, Technal 40 Figure 37 Office building Renovation , Calle de balmes , Barcelona , Xmas Arquitectura 41 Figure 38 Street Facade rennovation , Calle de balmes , Barcelona , Xmas Arquitectura 42 Figure 39 Hotel OMM Barcelona , Javier (2010) , https://www.flickr.com/photos/javier1949/5015380521/in/photostream/ 43 Figure 40 Hotel OMM Facade Skin, Javier (2010) , https://www.flickr.com/photos/javier1949/5015380521/in/photostream/ 44 Figure 41 Thermal mass in the interior absorbs the sunlight and radiates the heat at night. 47 Figure 42 Thermal Mass Wall or Trombe Wall Day and Night Operation 48 Figure 43 Trombe wall mechanism through day and night 49 Figure 44 Dry wall prototype, Universidad Politécnica de Madrid 51 Figure 45 Phase changing materials cycle 52 Figure 46 Day and Night Operation of a Sunroom Isolated Gain System 53 Figure 47 A Trombe wall (left) and attached sunspace (right) 54 Figure 48 Top View of Wing Walls Airflow Pattern, House-energy.com 55 Figure 49 Thermal Chimney mechanism, bigladdersoftware.com 56 Figure 50 Solar control glass , Pilkington 58 Figure 51 Optiphop noise reduction glass 59 Figure 52 Table of Nosie reduction glass products 60 Figure 53 Upper floor shows thermally insulated glass while lower floor is normal 61 Figure 54 Table of solar glass products 61 Figure 55 Plans and sections of shading devices 62 Figure 56 Vertical Louver , Locarno Louvers 63 Figure 57 Villa vertical louvers, Auckland, https://www.eboss.co.nz/library/locarno/operablevertical-louvres 63 Figure 58 Horizontal Louvers, Locarno Louvers 64 Figure 59 Remuera House , Auckland,https://www.eboss.co.nz/library/locarno/operablehorizontal-louvres 64 Figure60 BIPV Cells module 65 Figure 61 Pv cells output Power calculations 66 Figure 62 PV Panel Module 66 Figure 63 Paula Montal block Site Analysis 68 Figure 64 Solar average daily radiation in Wh/m2 of roof top and envelopes in the Paula Montal (south façades) 69 Figure 65 Solar average daily radiation in Wh/m2 of roof top and envelopes in the Paula Montal (north façades) 70 Figure 66 Paula Montal block site plan 71 Figure 67 Selected land plot site plan 72 Figure 68 Paula montal street façade 73 Figure 69 Paula montal Courtyard facade 73 Figure 70 Paula Montal block street facades 74 Figure 71 Paula Montal block courtyard facades 74 Figure 72 Facades which is not oriented on solar access 75 Figure 73 Facades which are oriented on solar access 75 Figure 74 Facades which are oriented on solar access 76 Figure 75 Facades which are oriented on solar access 76 Figure 76 Winter sun path analysis 77 Figure 77 Summer sun path analysis 78

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