An approach to urban micro space sustainability. Sustainable assessment instrument

Transcription

1 An approach to urban micro space sustainability. Sustainable assessment instrument Gómez Nersa 1 ; Higueras Ester 2 ; Ferrer Mercees 3 1 Instituto e Investigaciones, Faculta e Arquitectura Universia el Zulia - LUZ, Maracaibo Venezuela 2 Departamento e Urbanística, Escuela e Arquitectura Universia Politécnica e Mari UPM, Mari España 3 Instituto e Investigaciones, Faculta e Arquitectura Universia el Zulia - LUZ, Maracaibo Venezuela Abstract. The bet on new urban growth emans sustainable assessment instruments to keep coherence among the components that intervene in the urban ecosystem an environment, which supports them. This focus of this work is centere in the micro urban scale an the main purpose is to move forwar an instrument guie of plan assessment from the bioclimatic perspective an to propose sustainability strategies to be use in ecision making in orer to evaluate an esign the micro space among builings. This work proposes: (1) literature review about assessment systems, analysis scenarios an experiences achieve at an international level about key components of micro climatic scenarios of construction; (2) urban an environmental variables an inicators selection accoring to local micro urban reality, urban morphology an micro climate; an (3) a systemic proposal an key elements that act as control guies an sustainable esign of urban micro space. Key, wors, urban sustainability, urban micro space, assessment guie, variables, parameters-inicators of sustainability. Introuction One of the actual great challenges is the promotion of more sustainable urban moels with a more efficient use of resources (Ruea S, 2004). This manifests the nee to act at ifferent scales of public space by implementing new an innovative strategies that promote the use an appropriation of space an encourage sustainable changes in the urban fiel as well as to assume the objective of maintaining coherence among the components that intervene in the urban ecosystem along with the environment that supports them (Nikolopoulo et. al, 2003). Therefore, the approach of the work points towar the establishment of an instrument guie that states micro climatic scenarios as a tool of assessment an sustainable esign supporte by the microclimatic, morphotypological characteristics an its interconnection in the scale of urban micro space. 1

2 The particular interest of the work is to pose how to improve relationships an conitions of micro space from a systemic integral vision that combine the urban an environmental variable in supporting the social element in a balance way. This position ientifies with current urban purposes (sustainable evelopment, social cohesion, quality of life) that pose the incorporation of new strategies to join in planning techniques to move towars a sustainable relationship (European Union, 1996). The efinition of a systemic an comprehensive strategy for aequacy an control of intervening variables may act as a toolguie of control an esign in the urban micro scale. So, consiering this purpose a literature review on sustainable measures, assessment systems, variables an key components in the construction of micro climatic scenarios is state in the first place. Seconly, imensions of urban fiel, environmental an urban variables an inicators consistent with local micro urban reality. Thir, a proposal of scenarios an ifferent situations moeling as well as interrelationship of eterminant key variables, analysis control guie an micro space esigning. 1. Literature Review Current outlook shows a great quantity of approximations an the concurrence of many sustainable parameters that have been shown as a stanar tool since its incorporation in Local Agenas 21. Besies the recognition of their importance, agree strategies relate to sustainability that allow knowing the main problems consiere an use strategies are state in publishe literature that irectly iscusses the role in sustainable evelopment. Investigations have centere their efforts in measurements an sustainable assessment systems in orer to guie urban, environmental an social issues. Stuies mostly focus on objectives, analysis scenarios, ata availability, acting scales, selection, assessment an variables an inicators structure to promote urban sustainability. Likewise, they offer information on urban fiel imension specifically about physical an environmental imension linke to the social element. On the other han, these stuies highlight that physical structure confers an orer that gives a series of time-spatial benchmarks that supports the esire social moel, an manifest in the organization an istribution of elements in orer to provie the scenario for orinary activities. It is consiere that the mixture an interaction of typologies can remarkably improve socialspatial cohesion an act as a mechanism to establish corrections in orer to allow the ientification with the constructe environment. For this reason, space must be thought as a unit where climatic an physical components organize in a comprehensive vision that conitions the built environment an confers living character an social relationship. Stuies aress men-means-environment relationship that eals with the materialization of urban form an intervening elements within the aequate treatment an esign to place. Builing heights, ensity, compactness, insulation, vegetation, sun exposure, win exposure, shaows, istances, sizes, superficial materials an pavements are state as intervening elements 2

3 (Olgyay, 1968). All of these are recognize as intervening factors in thermal quality of environment among builings. Bustos Romero (1988) consiers factors such as localization, ventilation, win spee as well as orientation an insulation. He also highlights as intervening elements morphology, open, close, isperse, compact form, ensity, separation among builings, builing heights, barriers of win conuction, solar raiation exposure, nature of superficial elements an climate balance. In terms of the builing site, orientation, imensions, form, occupation, alignment, closures an superficial materials as well as vegetation, ventilation, shaows, presence of water, humiity an lightning are unerline. In the mentione stuies, there are coinciences of some constants such as intervening elements, which are groupe in three categories (Table 1). The categories an associate variables constitute the key elementscomponents that characterize the comprehensiveness of micro space an conform multiple imensions consiere in the construction of micro climatic scenarios of the micro space (Gomez, 2010). Climatic mean Urban morphology builing Solar raiation shaows Orientation Wins lightning Vegetation Structure an urban morphology Urban net Orientation Occupation ensity Builing heights Localization of builing site Size, geometry an lan surface Enveloping characteristics Builing elements Structural characteristics Materials /Finishes Color Pavements an walls Table 1. Categories of constant intervening variables in outer space In the propose systemic an moele statement, it was necessary to combine the relevant key elements consiering the three components-elements ientifie as: Environment, Base an Limit surface; these correspon to space, physical enveloping an the micro climate. The Environment involves climate conitions of such micro space; the Base correspons to space where micro space settles; the Limit surface refers to the limit or the frame of space that surroun us (Imagen 1). The elements that comprise this boy represent the synthesis an fit in the parts that interact an form the scenarios to be propose. 3

4 Environment Win Raiation Limit surface Base Vegetation Imagen 1. Components-elements of micro space The first component comprises the access to environmental elements such as: sun, temperature, humiity, sun raiation, shaes, wins, conuction an canalization of wins an vegetation. The secon component inclues the morphotypological factors of space locate in the base plan such as: occupation, builing typology, builing heights, localization an istribution in the lot, size, geometry an surface of the lot, pavements, walls an covers. While the thir component eals with the elements of the builing an the quality of the enveloping: surface area, openings, materials, finishes an color. These components act systematically in the micro space an must be treate simultaneously an interrelate linking the morphotypological an builing components with the micro climatic environment. In the stuy on sustainability, Kees (2006) proposes using the term situation to escribe the conition of micro space in its whole complexity. It refers to the capacity to keep elements together which are often heterogeneous by common situations, as well as giving them a common meaning. The term situation (taken from strategic planning) is useful, because it is about recognizing a moment within the continuous process of spatial, time an social transformation in which space is involve an it correspons to a comprehensive approach with a simultaneous strategic vision instea of a linear plan of following phases. Simultaneity an approach ensity revolve aroun a net capable of capturing the complexity of ifferent elements; it is a metho that allow facing the complexity, recognition, vision an comprehensive solution of the urban micro space. 1. Systemic strategy From the relationship system suggeste, it is propose the micro climatic scenario moeling as well as the main referents supporte in the review that combine parameters an highlighte intervening variables abroa. The heuristic approach, iterative among the key variables that efine the environmental behavior in orer to formulate micro climatic strategies in current urban evelopments were privilege (Gómez, 2010). This strategy 4

5 intens to meet comprehensive solutions from the sustainable esign principles. In orer to apply it, it is necessary to previously take a comprehensive evaluation of the micro space to etermine the place of the elements or conitionings of the polyvalent comprehensive conception; that is to say, the space in its three imensions. This analysis contributes to the efinition of esigning parameters incorporate to the materialization process of urban form. The strategy propose consists of the three (3) imensions of the stuy: the Environment, the Spatial Coorinate eals with the environmental conitions; the Base an Limit Surface, the Urban-Builing Coorinate inclues the morphotypological characteristics an builing an material characteristics; Time Coorinate, the use an scheule. These three coorinates form the System of Relationship or Strategy to buil micro climatic scenarios in the micro urban scale. The interconnection of components-elements an the comparison-synthesis of the system of relationships allow establishing an characterizing the constant within the micro space configuration. The main iea is to create a Strategic Guie for urbanenvironmental planning an esigning whereby the micro space has to have a efinite, esigne an built shape with as much intention as architecture. It is about the architectural conception of public space. Moeling: moeling comprehens spatial an environmental elements constant in public space an comprises the following phases: A. Selection of stuy areas accoring to propose criteria. B. Recors of ifferent situations of relationship among the components-elements: Environment, Base an Limit Surface accoring to the morph-urban conition (istances, orientation, surfaces), volumetric configuration (heights, imensions, elements) an pavements (types an properties) (Imagen 2) N Situation 1 V1 V2 Micro space Situation 2 V1 V2 h Micro space N 5

6 N Situation 3 V1 Elevation V2 h Micro space Plan view Imagen 2. Recor of ifferent situations of the components-elements C. Determination of scenarios for each registere situation through the interaction-contrast of components-elements for each spatial establishe unit. The system of relationships rules over the interaction of variables, which constantly intervene in the micro space an efine the three propose coorinates: spatial, time an urban-environmental. The purpose is to etermine the effects an strategies of thermal control. C.1 Environment an Base Relationship. Variables of components-elements interconnect to achieve strategies that guarantee exterior comfort. In orer to obtain Solar Block, orientation, localization of elements, ensity an istance among builings are interrelate, which contributes to guarantee permanent shaow in the micro space (Table 2). The greater the ensity is, the greater is the possibility of shaow accoring to the cast shaow. Likewise, the isposition an iscrepancy of builings promote the prouction of cast shaows towars the surrouning environment. The correlation between orientation an imensions of the lot allow controlling the angle of exterior solar obstruction, an the curve of solar obstruction amits the orientation of space towars etermine situations. Environment an Base Relationship BASE Environment Dimension of the lot Localization of elements Density Distance among builings Type of pavement Color Pavement properties Orientation Solar block Surface Control Raiation Ventilation Movement of the air Solar raiation control Vegetation Solar raiation control Solar raiation control Table 2. Environment an Base Control Orientation, pavements, type, color an surface properties are linke in orer to control Solar Raiation. This interrelationship contributes to efine the typology of exterior surfaces accoring to reflection coefficients. On the other han, win, orientation, istribution of 6

7 usages, ensity an localization of elements are linke in orer to control the movement of air effects of rotation an flow; so, this contributes to air movement an aequate flow of ventilation. While for vegetation, imension of lot, isposition (m 2 per person) an green istribution are interrelate. The presence of green intervenes in the control of solar raiation an as a vegetable protector. C.2 Environment an Limit Surface relationship. In orer to control raiation, orientation, location of façaes an volume imensions of variables accoring to the angle of solar obstruction are linke (Table 3). This help to control sun exposure an to reuce sun hours as well as to guarantee self-protection an permanent shae of the environment. Orientation, height an separation of builings must be consiere for each orientation. Leveling is not permitte. For passive conitioning, the following variables ventilation, typology of the builing an volume imensions are linke. The relationship among orientation, block typology, imensions of openings, surface finishes an protective elements conitions ventilation crossing an acts as a barrier that can generate changes of irection an win spee as well. In orer to control vegetation, the green an the built enveloping as a protection measure an as vegetable framer an protection cover. Environment an Limit Surface relationship Limit Surface ENVIRONMENT Heights Volume imensions Builing typology Enveloping surface Distance among builings Orientation Solar block Solar block Raiation Solar raiation control Ventilation Open block Passive Conitioning Vegetation Solar raiation control Table 3. Environment an Limit surface C3. Environment timing perio relationship. The components Base an Limit Surface per spatial unit with temperature, solar raiation an ventilation uring representative perios of time accoring to climate an micro space orientation are interconnecte (Table 4). Thermal variables that act in combination are compare to Comfort ranges of local Psychometrical Diagram, which establishes the levels of comfort guarantee. The type an istribution of vegetation is another variable to control. 7

8 Environment timing perio relationship PERIOD - TIME ENTORNO Morning perio Meriian perio Evening perio Orientation Temperatura Raiation Physical an urban characteristics Physical an urban characteristics Physical an urban characteristics Ventilation Vegetation Table 4. Environment timing perio Control From these moels, the construction of computer simulation scenarios are is feasible in orer to evaluate the variable behavior accoring to every single situation. Analysis an comparing components coul allow establishing the aequate thermal requirements within the urban micro space. REFERENCES (1) Bustos, R, M. (1988). Principios Bioclimáticos para o Desenho Urbano. Tesis e Doctorao: Universia e Sao Paulo. Brasil. (2) Unión Europea (1996). Informe e Ciuaes Sostenibles. Comisión Europea. Dirección General XI Meio Ambiente, Seguria Nuclear y Protección Civil. [Documento en línea]. Disponible En: - es. (3) Gehl J (2006). La Humanización el Espacio Urbano. Estuios Universitarios e Arquitectura. España. (4) Nikolopoulou, M., y Steemers, K. (2003). Thermal comfort an psychological aaptation as a guie for esigning urban spaces. En Energy an Builings, 35(1), pp (5) Kees C (2006). Sostenibilia en el iseño urbano en Eco-Barrios en Europa. Nuevos entornos resienciales. Mari: (6) Olgyay (1968). Design with Climate. Princeton University. Princeton (7) Givoni B (1989). Urban Design in ifferent Climate. Report WMO/TD-No.346, Worl Meteorological Organization. Geneve. (8) Gómez N (2010). Microclimatic stuy of the space between builings. Case: Urban housing evelopments, Maracaibo (Venezuela)". En Revista Técnica. Faculta e Ingeniería, Universia el Zulia-LUZ. 8