The green space factor as a tool for regulating the urban microclimate in vegetation-deprived Greek cities.

Transcription

1 he green spae fator as a tool for regulating the urban mirolimate in vegetation-deprived Gree ities. A. Vartholomaios 1*, N. Kalogirou 1, E. Athanassiou 1, M. Papadopoulou 2 1 Department of Arhiteture, Aristotle University of hessalonii, 54124, hessalonii, Greee 2 Department of Rural and urveying Engineering, Aristotle University of hessalonii, 54124, hessalonii, Greee *Corresponding author: avarth@arh.auth.gr, el: Abstrat he Green pae Fator (GF) is an innovative and flexible urban planning tool whih aims at improving green infrastruture in private open spaes. After it beame a popular measure in Berlin, more ities, suh as Malmö, eattle, outhampton and toholm have inluded it in their environmental planning toolit. he GF an be integrated in the Gree planning system, as the la of publi vegetated spaes an be ounterbalaned to a degree by greening private open spaes and building surfaes. he paper sees to explore the possibility and effetiveness of employing the GF in the ontext of Gree ities. It starts with a omparative analysis of existing appliations of the GF in different urban and legal ontexts. ubsequently, the paper suggests an analogous planning tool for the Gree ity. he suggested tool is further explored through its appliation at different plot onfigurations. 1. INRODUCION Nowadays several ities globally are pursuing an ative environmental agenda in order to reonnet man and nature, redue onsumption of energy and materials, reate a thermally omfortable urban environment and forge a new green identity. he Green pae Fator (GF) is a relatively new planning tool, urrently employed by metropolises and small ities alie to ahieve these objetives. Position of this paper is that the Green pae Fator an be integrated into the Gree planning system to reintrodue vegetation in Gree ities and therefore aid towards the improvement of the their burdened urban limate. he GF onstitutes a flexible and innovative planning tool that quantifies and assesses the quality of eologial and limati funtions of private green infrastruture. It aims at inreasing the quality of urban landsaping by setting ertain development standards. he GF was initially applied to Berlin and other ities, suh as Malmö, eattle, outhampton and toholm soon followed. At a regional sale, the GF was applied at North est England. In ontrast to an inentive-based approah to environmental interventions, the GF is a regulatory measure, although this does not exlude the possibility of being used along with inentives. he GF relies on the standardization of several environmental features and the quantifiation of their eologial benefits. A list of features whih are fatored aording to their relative eologial signifiane is provided by the loal authorities in the form of a worsheet for easy alulation. Individual fators usually range from 0 to 1. he GF is used to aomplish several goals, inluding urban limate regulation, redution of energy and water onsumption, flood ontrol and restoration of the hydrologial yle, preservation and enhanement of wildlife habitats and improvement of urban aesthetis. However, priorities may differ from plae to plae. Proeedings of the International Conferene on Changing Cities : patial, morphologial, formal & soio-eonomi dimensions IBN: , iathos island, Greee, June 18-21,

2 As the formulae used by the ities to ompute the GF are almost idential, a generi GF formula an be derived: here area i is the area of eah GF feature i, fator i the weight of eah intervention i and total area the total area of the plot whih may or may not inlude the area of the building s footprint, depending on eah ase. 2. APPICAION OF HE GREEN PACE FACOR 2.1 Berlin s Biotope Area Fator. he City of Berlin was the first that oneptualized and implemented the Biotope Area Fator (BAF) during the nineties, in order to ounterbalane the defiits of open spaes in the densely-built inner ity by upgrading eologially areas of private property. he BAF initiative was a part of the andsape programme, whih was introdued in 1984 in est Berlin. he BAF is a legally binding fore in areas with a andsape Plan, whih urrently over about 16% of Berlin. he andsape Plan regulates development aording to the strategy set out by Berlin s andsape Programme. Outside these areas, the BAF is voluntarily used as a guideline for enouraging the use of environmental features. he BAF is implemented on the basis of planning permits for both extensions to existing development and new development [1]. he minimum BAF target is relative to the designated land uses and depends on whether the development is new or an extension. he BAF target ranges from 0.60 for new residential units, publi failities and nursery shools to 0.30 for ommerial, ity entre and tehnial infrastruture uses and for extensions to existing residential units and publi failities. he value of 0.30 represents a minimum standard whih is ahievable, even for very high density development [1]. he BAF rewards eologially effetive surfaes in ontrast to hard impermeable surfaes that prevail in the ity. he onnetedness of unovered topsoil with the subsoil is highly rewarded, as it allows spae for development of the root system of flora, replenishment of underground aquifers with rainwater, as as well as penetration of air and nutrients. In the ase of high density development on small land parels green roofs and walls have to be employed in order to meet the minimum BAF target. he weaness of this approah is that it is indifferent towards different types or qualities of vegetation. For example, an area with sparse vegetation and a group of trees with extensive undergrowth of equal area would reeive the same sore as long as the topsoil surfae is onneted with the subsoil. Moreover, the BAF has reeived ritiism for being too proedurally intense, requiring a lot of effort on the ity s behalf, regarding initial researh and ontinuous evaluation of the programme. However, its flexibility has made it a popular environmental initiative [1]. 2.2 Malmö s Green pae Fator. Following the example of Berlin, the City of Malmö introdued the Green pae Fator (GF) for the redevelopment of the estern Harbour. he vision for the estern Harbour is to reate an environmentally sustainable urban distrit. he neighbourhood of Bo01, the first ompleted stage of development, is alaimed as a leading example of eologial urbanism. he minimum GF target was set to 0.5 for Bo01. he method of alulation is different from Berlin s BAF sine some vegetation qualities, suh as their type and size are fatored in and it is also possible to layer different surfae over types to ahieve a higher GF. Hene, an area with signifiant vegetation an sore more than 1.0 whih is the maximum sore for a speifi surfae type. rees and bushes planted on onneted soil, water features and green roofs sore highly. A Green Points helist is also used in onjuntion with the GF to desribe landsape qualities that are not (1) 1021

3 easily standardized or quantified. Developers have to inlude in the development proposal 10 out of 35 available features whih inlude shelters for birds and bats, preferring meadows and semi-natural biotopes over mown lawns, greening all roofs or overing all walls with plants [2]. Most of these interventions have a strong eologial harater. During the development stage of Flagghussen, another neighbourhood of the estern Harbour distrit, a different approah of reative dialogue among the staeholders was used. he reative dialogue between planners and developers aimed at ahieving environmental goals at a realisti ost, to ounterbalane the high pries of dwellings built in Bo01. he minimum GF target beame relative to the building overage. he higher the building overage, the lower the GF minimum target. his was justified by the fat that high density areas have very few private open spaes to utilize for greening [2]. he evaluation and monitoring of the appliation of the GF in Bo01 onluded that most development ahieved the minimum GF target. In ontrast, a similar assessment of the effiieny of the reative dialogue approah in Flagghussen onluded that not a single developer had aomplished an aeptable result. his led to a strengthening of the GF by raising the minimum required sore to 0.6 and lowering the value of several individual fators [2]. 2.3 he eattle Green Fator. he eattle Green Fator (GF) was modelled after Malmö s GF and Berlin s BAF. It was adopted in 2006 for ommerial zones and was revised in early 2009 to inlude residential multifamily units. he GF minimum targets were set aording to land use zoning. For various ommerial land uses the minimum is 0.3, for mid-rise and high-rise multifamily residential 0.5 and for low-rise multifamily residential 0.6 [3]. Green roofs and walls and permeable pavements are given higher fators to enourage their use. Moreover, additional bonus points are given for use of harvested rainwater, planting native speies, visibility of landsaping from the street and loal food ultivation. Exeptional or preserved trees get more points than large trees, while some points are given for strutural soil systems, whih help the soil retain its original properties in the urban environment. 2.4 he Green Infrastruture ore of North est England. he Green Infrastruture ore (GI ore) was developed by the North est Development Ageny (NDA) as part of its ustainable Buildings Poliy. However, the reent abolition of the NDA in 2011 has downgraded the poliy to the status of guidane. he GI sore is used in onjuntion with a GI Interventions worsheet in a way equivalent to Malmö s Green Points system. he available GI Interventions orrespond to the eleven eonomi benefits set out by Natural Eonomy Northwest, whih inlude limate hange adaptation, flood alleviation, biodiversity and plae quality. Planning appliations that justify how multiple benefits are ahieved through developing the site would be onsidered favourably [4]. A minimum GI ore of 0.6 is speified for development on vaant plots. However for development on plots with existing strutures the GI ore of the proposed development should be higher than the pre-development GI ore by 0.2. Vegetation planted on topsoil onneted to the subsoil, green roofs and water retention areas sore highly [4]. 2.5 outhampton s Green pae Fator. he outhampton City Counil following the aforementioned examples reated its own GF tool whih is now required for the development of one or more dwellings or any development of more than 500m 2 [5] he tool is used as part of the ustainability Chelist to demonstrate suffiieny of green infrastruture in the proposed development, hene no minimum GF target is set. he us- 1022

4 tainability Chelist is used by appliants who wish to obtain planning permission by demonstrating ompliane to ey priniples of sustainable development as set out by the City of outhampton s Core trategy Poliy. ie Northwest England s GI sore, the developer has to prove that there is a substantial inrease of the GF of the proposed development when ompared to the pre-development GF. A Geographi Information ystem (GI) was also used to determine the existing pre-development GF, whih was found to be equal to 0.38 for the whole ity and 0.16 for the ity entre alone. It was also possible to predit that the inlusion of green roofs on all buildings would inrease the ity entre s GF by 0.22 [5]. 2.6 toholm s Green pae Fator. toholm s Royal Urban eaport, a 236 hetare industrial site is to be redeveloped into an environmentally sustainable neighbourhood. Development has started in 2010 and is expeted to be ompleted in Malmö s GF was adopted and further refined. he minimum GF target is 0.6. toholm s GF is differentiated from other examples by the addition of more detailed fators on biodiversity, soial use of green spae and limate adaptation. For example butterfly restaurants, fruit-bearing flora, nesting boxes, lawns suitable for ball games and play, food ultivation on balonies, multi-layered green roofs, trees and pergolas shading playgrounds get additional sores [6]. Hene, some of the qualities desribed in the Malmö s Green Points ystem are integrated into a more detailed list of possible features, offering a larger degree of possible ombinations. As the Royal Urban eaport is still under development, no monitoring and assessment of the GF has yet been made. 2.7 ummary of the GF appliations. he onept of GF remains more or less the same sine its first appliation in Berlin. ome hanges were made to adapt it to loal planning onditions and modify eologial priorities. ine the GF is relatively new, ities tend to pilot test it to ertain neighborhoods or land uses before applying it at a wider sale. In most ases the absolute minimum GF target is 0.3, whih is believed to orrespond to a minimum of green infrastruture that human settlements should ahieve, regardless of density or land use. However, a minimum target of is often set for new developments, where there is still room for ahieving a higher environmental quality at the design stage. able (1) illustrates the ey differenes between different appliations of the GF: Name Area of appliation Minimum target able 1. ummary of the ey differenes of the GF appliations to the examined ases. Berlin Malmö eattle toholm N England outhampton Biotope Area Green pae Green pae Green Infrastruture ore eattle Green Fator Green pae Fator Fator Fator Fator Compulsory in Compulsory Voluntary. Required for development of one areas with Required for Compulsory for new for Royal ine 2011 the andsape est Harbour Rede- ommerial or multifamily development. Redevelop- downgraded to or more than eaport poliy has been or more dwellings Plans. Voluntary for rest of velopment ment guidane. 500sq. meters. Berlin Ranging from 0.6 for new residential units to 0.3 for ommerial zones. 0.5 and later raised to 0.6. Commerial and downtown 0.3, multifamily midrise and high-rise 0.5, multifamily low-rise for vaant plot development, a +0.2 differene from pre-developed phase for extensions. No minimum speified. Used to demonstrate suffiieny of green infrastruture. ayering no yes yes yes yes yes Green points no yes no no yes no he eologial aims of the GF are almost idential in all examined ases. he GF is used to provide wildlife habitats, manage storm water, regulate the loal limate, improve urban aesthetis and 1023

5 redue air, soil and water pollution. In most ases, high fators are assigned to features suh as green roofs and walls, water features and the preservation of large trees. he size of trees is usually determined by their rown size whih is also used to alulate their effetive area. For example for Malmö shrubs are alulated at 2m 2, small trees at 5m 2, medium trees at 15 m 2 and large trees at 20m 2 eah. imilarly, in most ases, green walls are alulated aording their 5-year projeted overage, whih may have an upper limit, usually around 10m. able (2) ompares fators given to different features. For an easier omparison, the individual features and their properties are provided in a simplified way and tehnial details are omitted. able 2. Comparison of the fators attributed to individual GF features for eah examined ase. Berlin Malmö eattle N England outhampton toholm vegetation on shallow unonneted soil ! " # $ % % & $ ' ( ( ) ) * " +, " -! $ - ).! $ / ) % $ 0 0! ( 1 '. % 2 vegetation on deep unonneted soil vegetation on onneted soil water surfaes N/A olletion/retention of storm water permeable pavement and partially-sealed areas (no vegetation) 0.3 N/A 0.2/0.5 (1) areas overed with gravel or sand Green pavers 0.5 N/A N/A trutural soil systems N/A N/A 0.2 N/A N/A shrub tree - small tree - medium N/A per m2 of tree - large anopy over 2.4 tree - proteted/exeptional N/A green roofs /0.7 (2) /0.4 (2) vegetation on vertial surfaes bonuses for speifi vegetation qualities no no yes no no yes 3! % & $ ' ( # 1. # / ). ) - $ - 1 ' # ) 1. # - $ 0 0! ( 1 '. % 2 he main strengths of the GF are the following: It is flexible; it sets a minimum design standard and it is up to the developer to deide how to ahieve it. herefore, interferene with arhitetural freedom is ept to a minimum. It follows the same logi as planning ratios and an be lined to lot overage and density. Planners and Developers an quily get austomed to it and the method is transferrable from plae to plae. Its regulatory role ensures that minimum standards will be met in ontrast to providing inentives or engaging in a dialogue with developers, as the ase of Flagghussen shows. On the other hand, the required ommitment, in terms of effort and finanial soures, of the loal authorities to its development, dissemination and on-going evaluation has been mentioned [2] as a weaness of the GF. 3. PRIVAE OPEN PACE A A KEY CIMAIC REGUAOR OF GREEK CIIE. It is well nown [7] that the limate of ities is differentiated from the rural limate of the same region. he limate of Athens is burdened as the Urban Heat Island (UHI) intensity, i.e. the air temperature differene between the ity and its surroundings, an reah 6 C in the suburbs and exeed 10 C in ertain parts of the ity entre [8]. imilarly, the UHI intensity in hessalonii ranges from 2 o C to 4 o C [9]. Medium-sized Gree ities, suh as Patra, Volos and Heraleion also demonstrate a 1024

6 surfae temperature differene with their surroundings of about 2-3 C [10]. he ey fators that alter the limate of Athens are the high-density urban ontinuum laing adequate vegetation, the domination of materials with high heat apaity lie onrete and asphalt, the prodution of anthropogeni heat and air pollution. A similar development model has been followed in most Gree ities, resulting in similarly dense urban fabris laing adequate green spae. It an be assumed that suh features ombined with heavy traffi result in similar limati onditions. Publi green infrastruture of Gree ities is inadequate in general terms. For instane, it is estimated that Athens and hessalonii provide roughly about 2.5m 2 and 2.7m 2 of green spae per apita respetively [11], in ontrast to the minimum of 8m 2 suggested by the Gree Planning tandards [12]. Moreover, the few publi open spaes are often fragmented, unevenly distributed in the urban tissue and poorly designed in environmental terms while vegetation is often mismanaged or absent. he prevalene of impermeable surfaes in open spaes disrupts the hydrologi yle, leading to a generally drier urban environment, suseptible to flooding during heavy storms. Private spaes inbetween buildings are also sealed off with impermeable materials are often used as paring spaes and are rarely vegetated. Often, they are inaessible and ompletely unmanaged. One of the ey interventions that are apable of regulating the limate of Gree ities is the extensive overage of available surfaes with vegetation. he limati benefits of vegetation inlude the loal derease of air temperature through the proess of evapotranspiration and the provision of solar and wind protetion. Additionally, it balanes the natural yles of oxygen, water and arbon, prevent soil erosion, an at as noise barrier, filter ertain air pollutants, provide shelter to urban wildlife and ontribute to loal food supply. Inside pars with dense tree overage a onsiderable derease of air temperature by 4 to 7 C has been observed during hot days in Athens [13]. However, the range of the temperature redution effet of urban pars is usually small, as it rarely exeeds one or two urban blos, usually to the leeward side of the par [13,14,15]. he presene of trees near buildings is also assoiated with a redution of surfae temperatures of buildings and energy savings [13,16]. Additionally, the ombination of green walls and roofs an lead to a redution of loal air temperature of up to 6.5 C for the entre of Athens [17]. herefore, there is a need not only to inrease the amount of urban greenery but also to distribute vegetation more evenly in the urban tissue and as lose as possible to buildings. his requires an urban design strategy that pursues the extensive vegetation of both publi and private building plots as well as the greening of building faades and roofs to maximize the limati and eologial benefits of greenery in densely-built environments. Another important strategy for mitigating the UHI effet is to minimise the sealing of the ground with impermeable materials suh as onrete or asphalt. his strategy is also useful for restoring the hydrologi yle in ities. he use of green pavers, porous pavements or ool materials [18] an be promoted as a viable alternative. uh landsaping strategies an be realized by adopting new regulatory tools suh as the Green pae Fator in the Gree planning proess. 4. EXIING ANDCAPING REGUAION IN GREECE. andsaping of private property in Gree ities is regulated by the New Building Code (NBC), whih was introdued in 2012, replaing the General Building Code (GBC) whih was valid, with one intermediate revision in 2000, sine he NBC has a nation-wide appliation, unless loal plans provide striter speifi regulations. Aording to the GBC (artile 23), two thirds of the open spae of plots in areas with an approved urban development plan need to be left unpaved for plant- 1025

7 ing. Development on plots larger than 200m 2 need to retain existing or plant new trees to ahieve a overage of one tree per 200m 2. peifially, front yards must be planted at a density of one tree per 25m 2 [19]. he NBC does not mae any signifiant hanges to GBC s landsaping regulations. However, it speifies green roof standards for the first time and sets a limit to the area of permissible underground strutures, whih annot extend to more than half of the unbuilt area of the plot, to preserve the onnetedness of the soil [20]. Another new aspet of the NBC is the new Environmental Bonuses whih offer an inrease of the maximum permissible plot ratio in exhange for lower plot overage, thus enouraging taller buildings and higher densities. he NBC does not inlude a mehanism for seuring the quality of the saved-up spaes, other than the aforementioned landsaping regulations. he landsaping regulations of the NBC ould be haraterized as inflexible. he requirement of vegetating two thirds of private open spae is often inompatible with the high plot overage and plot ratios, the subsequent ar paring demand and the small urban plots that are the norm in Gree ities. he obligation to plant a tree per 200 m 2 of open spae ould be regarded as inadequate. Moreover, no speifiations are given regarding the quality and suitability of vegetation and no distintion is made for mature trees, whih should be preserved as muh as possible. Additionally, the new Environmental Bonuses do not tae into aount the fat that higher densities inrease the demand for ar paring, whih ould have a negative impat on the quality of the urban landsape. 5. HE GREEN PACE FACOR A A FEXIBE OO FOR HE ENVI- RONMENA UAINABIIY OF HE GREEK CIY. he GF an be integrated into the Gree planning system as a tool for improving the environmental performane of private open spaes, thus ontributing to the regulation of the limate of Gree ities. A future amendment of the Building Code ould inlude the GF as a replaement of urrent relevant regulations. Alternatively the GF ould be adopted within the framewor of a loal development plan. In any ase, the tool should not be simply imported but needs to be optimized for the speifi onditions of Gree ities and limate and tested extensively. his paper proposes a general framewor that an beome the basis for further researh. For an initial pilot study the GF an be applied to residential and mixed residential uses (low and medium degree of land use mixing respetively), setting a minimum GF target of 0.5 for development on vaant plots and 0.3 for already developed plots. Individual features and their fators are provided in able (3) below. he proposed features are found in all appliations of the GF in the examined ases. Emphasis is given to elements that an atively regulate the urban mirolimate, suh as medium and large trees, green roofs and walls or pergolas and water surfaes. Moreover, a bonus is given to trees loated in the front yard. able 3. ist of proposed features and their individual fators : 7 ; : 7 ; 9 / ). ) - $ - 1 ' ' 0 ' ' ) 0 - ) ( " 1 % < = > -! ) )? $ % % $ - A * )! -! ) ) < = B / ). ) - $ - 1 ' ' + ' 0 ' ' ) 0 - ) ( " 1 % < = 3 -! ) ) ( 1 $ - 3 A * )! -! ) ) < = C * ) $, % ) * $ / ) ' - " < = D -! ) $ - +! ) $ - D A * )! -! ) ) = <.! ) ) ' * $ / )! "!.! $ / ) % < = E.! ) ) '! " < = B & $ - )! " +! $ 0 ) " = < / ). ) - $ - 1 ' ' / )! $ % " +! $ 0 ) " < = F " #! +, " < = > -! ) ) " 1 '! ' - 2 $! ( ) G -! $, ' + " < = 3 For a preliminary analysis, the proposed GF is applied to three real-world examples of multifamily residential buildings, loated in hessalonii, Greee. oures of the olleted data were the online 1026

8 o [ Q g [ g [ GI servies of hessalonii [21] and Kalamaria [22] Muniipalities and the Helleni Cadastre s online orthophoto servie [23]. he basi morphologial harateristis were derived using oblique aerial photos provided by Mirosoft s Bing Maps [24] and were verified by a site visit. he GF is alulated twie for both ases of extension to or retrofitting of existing development and new development. Its alulation is just an example of how the developer might hoose a ombination of GF features. he 3D models that aompany the alulations demonstrate the use of the seleted GF features for the ase of new development, through the use of symbols for trees and bushes and textures for green and paved areas. he first example (Figure 1) is a five storey building with a footprint of 120m 2 situated on a plot of about 250m 2. It was built in the 90 s under the GBC of 1985 at a plot ratio of 2.1 and a maximum overage of 70%. As it follows the old ontinuous system of development it demonstrates a lear separation between the front and ba yard. Although the presene of a front yard allows for extensive planting, the ground floor is used for ar paring, thus limiting the spae available for vegetation. his onstitutes a ommon ase in Gree ities, where pilotis mae up for the la of adequate on-street paring spaes. he alulated GF sores above the minimum target of 0.3 for the ase of existing development. For new development, the developer would have to hoose additional features suh as a green roof. he piture on the left demonstrates how: H I J K J M N O P Q U Y p V P K j q _ d a P P V K P N P J U M U M U M M P P X K U J Y P N P J U M U M ^ M U M M P P X K U J Y P V a P Y P P a P M K b N V P P M P V K U V N V P Y P V K ^ V f P K K h V ^ K j a P V K h V ^ b i b V P P l K a Y Y g K j a P V V P P i V P P l a P X J ^ a K j a P V V P P i V P P l a ^ V P K j a P V V P P N V P P M V U U f K i P N P J U M U M P V J Y K ^ V f P K V P P K U M f V U M n V X P I V U M ^ K b Figure 1. First example of GF appliation. U V R V P a s i [ \ ] \ ] \ [ _ [ d e d e [ d [ \ [ ] _ [ m _ [ ] m [ d g g r p [ _ R q [ d [ d ] he seond example (Figure 2) is a mixed-use residential building with a footprint of 230m 2 situated on a plot of 380m 2. It was built in early 1980 s, under the GBC of 1973, at a plot ratio of 2.1 and at 50% overage. It an be observed that the developer hose to use up all the available overage. A narrow set ba of 1.50m imposed on a square plot produes a fragmented private open spae. ine most of the open spae is used for ar paring, the developer would have to over the blind wall with vegetation, in order to omply with the GF minimum for extensions and retrofitting. For new development, he would have to ombine it to a green roof to meet the minimum GF standard. It an be observed that in this ase, the hoies are limited. he higher fators assigned to green walls and roofs tend to promote them as viable hoies in high-density urban areas. 1027

9 o o [ [ Q Q g [ g [ g [ g [ g \ g g d g m e _ g \ g _ g m g e e U Y p V P q K j m a P P V K P N P J U M U M U M M P P X K U J Y P N P J U M U M ^ M U M M P P X K U J Y P V a P Y P P a P M K b N V P P M P V K U V N V P Y P V K ^ V f P K K h V ^ K j a P V K h V ^ V P P l b K a i Y Y g K j a P b V V P P i V P P l a P X J ^ a K j a P V V P P i V P P l a ^ V P K j a P V V P P i N V P P M V U U f K P N P J U M U M P V J Y K ^ V f P K V P P K U M f V U M n V X P I V U M ^ K b Figure 2. eond example of GF appliation. U V R H I J K J M N O P Q V P a s i [ \ _ [ _ g g [ [ d g g [ \ m m [ ] [ m [ ] ] [ d r p [ _ R q [ m [ d ] he third example (Figure 3) is a group of residential apartments of a total area of 820m 2 situated on a plot of 3000 m 2. hey were built in 2003 under the GBC of 2000 with a maximum plot ratio of 0.8, the maximum allowed aording to urrent Gree planning legislation and at a overage of 70%. A lower plot ratio ombined with larger plots and urban blos, ommonly found in the outsirts of the ities, tend to generate an urban landsape where building volumes are plaed more freely in the urban tissue. he developer has a high degree of hoie and an ombine multiple features to reah the minimum GF target. H I J K J M N O P Q U Y p V P q 6. CONCUION K j a P P V K P N P J U M U M U M M P P X K U J Y P N P J U M U M ^ M U M M P P X K U J Y P V a P Y P P a P M K b N V P P M P V K U V N V P Y P V K ^ V f P K K h V ^ K j a P V K h V ^ b i b V P P l K a Y Y g K j a P V V P P i V P P l a P X J ^ a K j a P V V P P i V P P l a ^ V P K j a P V V P P N V P P M V U U f K i P N P J U M U M P V J Y K ^ V f P K V P P K U M f V U M n V X P I V U M ^ K b Figure 3. hird example of GF appliation. U V R [ \ ] d _ ] d _ [ _ [ _ [ d _ [ \ [ ] [ m [ ] [ d r p [ _ R q V P a s i ine its first appliation in Berlin, the GF has beome a valuable tool for translating landsape design standards to planning regulations. Its ease of use, responsiveness, flexibility and transferability potential are reasons behind its popularity. he results from the preliminary investigation of GF s appliability in the Gree planning framewor demonstrate that the GF an suessfully regulate private green infrastruture of both new and existing development in urban areas. herefore, it an ontribute positively towards improving the environment of densely-built and vegetation-deprived Gree ities, an objetive that seems unahievable under existing regulations. Unlie urrent landsaping regulations, the GF retains its regulatory role while allowing the developer to hoose how to meet the minimum standards. his an be partiularly useful in the ontext of Gree planning, where the existing voluminous legislation, by imposing stiff measures and generi geometri onstraints, is often unresponsive to the ontext of eah speifi development ase. Moreover, the GF ould ooperate with the new Environmental Bonuses of the NBC, thus ensuring g g [ \ _ g g [ d 1028

10 the delivery of high quality private open spaes as the legislator originally envisioned it. he inlusion of the GF in the Gree planning system is not a ure-all by any means. However it onstitutes a omponent of a muh-needed overhaul of planning legislation oriented towards a new model of environmentally responsive urban development. Referenes 1. (aessed Deember 16, 2012). 2. Kruuse A., GRaB Expert Paper 6: he Green pae Fator and the Green Points ystem, CPA, ondon (aessed Deember 16, 2012) (aessed Deember 16, 2012) (aessed Deember 16, 2012) (aessed Deember 16, 2012). 7. Arnfield J., wo deades of urban limate researh: A review of turbulene, exhanges of energy and water, and the urban heat island, International Journal of Climatology, 23, antamouris M., Papaniolaou N., ivada I., Koronais I., Georgais C., Argiriou A., Assimaopoulos D.N., On the Impat of Urban Climate on the Energy Consumption of Buildings. olar Energy, 70 (3), Giannaros.M., Melas D., tudy of the urban heat island in a oastal Mediterranean City: he ase study of hessalonii, Greee, Atmospheri Researh, 118, tathopoulou M., Cartalis C., Daytime urban heat islands from andsat EM+ and Corine land over data: An appliation to major ities in Greee, olar Energy, 81, (aessed Deember 16, 2012). 12. Ministerial Deree 10788/5-3-04, Government Gazette 285, Greee. 13. antamouris, M. (ed), Energy and Climate in the Urban Built Environment, James & James, ondon. 14. hashua-bar., Hoffman M.E., Vegetation as a limati omponent in the design of an urban street An empirial model for prediting the ooling effet of urban green areas with trees, Energy and Buildings, 31, Honjo., aaura., imulation of hermal Effets of Urban Green Areas on their urrounding Areas. Energy and Buildings, 15-16, Abari H., Davis., Dorsano., Huang J., inert., Cooling our ommunities A guideboo on tree planting and white oloured surfaing, U Environmental Protetion Ageny, ashington. 17. Alexandri E., Jones P., emperature dereases in an urban anyon due to green walls and green roofs in diverse limates, Building and Environment, 43 (4), antamouris, M., ynnefa, A., Karlessi,., 201. Using advaned ool materials in the urban built environment to mitigate heat islands and improve thermal omfort onditions, olar Energy, 85(12), General Building Code N.1577/1985 as amended by N.2831/2000, Government Gazette 140 ', Greee. 20. New Building Code, N.4067/2012, Government Gazette ' 79/ , Greee (aessed Deember 16, 2012) (aessed Deember 16, 2012) (aessed Deember 16, 2012) (aessed Deember 16, 2012). 1029