The Impact of Archetype Patterns in Office Buildings on the Annual

sustainability

Article The Impact of Archetype Patterns in Ofﬁce Buildings on the Annual Cooling, Heating and Lighting Loads in Hot-Humid, Hot-Dry and Cold Climates of Iran

Jalil Shaeri 1,*, Mahmood Yaghoubi 2 , Amin Habibi 1 and Ata Chokhachian 3,*

1 Faculty of Arts and Architecture, Shiraz University, Shiraz 718773-35, Iran; [email protected] 2 School of Mechanical Engineering, Shiraz University, Shiraz 7196481334, Iran; [email protected] 3 Chair of Building Technology and Climate Responsive Design, Technical University of Munich, Munich 80333, Germany * Correspondence: [email protected] (J.S.); [email protected] (A.C.)

Received: 5 November 2018; Accepted: 3 January 2019; Published: 9 January 2019

Abstract: Extensive cost in the building industry comes from cooling and heating to create thermal comfort. Hence, it is necessary to utilize passive solutions, in addition to suitable design, in order to reduce energy consumption. This research attempts to investigate the impact of archetype patterns in ofﬁce buildings on annual energy consumption for cooling, heating and daylight loads. For this purpose, the DesignBuilder software was used to compare the forms. In this study, four conventional construction forms were considered, including the single and dense form, central courtyard buildings, U form and linear form, and each was considered with two, four and six-stories. Forms were simulated in the three cities of Bushehr, Shiraz and Tabriz, with hot-humid, hot-dry and cold climates, respectively. The results revealed that the ofﬁce building with a linear form in Bushehr had the lowest energy consumption in the two and four-story forms, and also in the six-story form, the central courtyard form had the lowest energy consumption. Additionally, the central courtyard forms in Tabriz and Shiraz had the lowest energy consumption in all cases. Finally, the linear form possessed the most natural daylight through all of the studied cases for the three cities in terms of natural light gain.

Keywords: form; archetype; ofﬁce building; cooling load; heating load; daylight

1. Introduction After the Industrial Revolution, the use of fossil fuels has signiﬁcantly increased in order to enhance the thermal comfort of the indoor environment. This, in turn, has revealed the remarkable share of energy consumption that is allocated to the construction sector, where cities are responsible for 70% of produced carbon in the world [1]. Today, 50% of the world’s population lives in cities, and this number will grow up to 80% by 2030 [2], which makes energy savings for buildings an absolute necessity [3]. One way to reduce the energy consumption and greenhouse gases of buildings, is the reformation of the building forms [4], where, by the proper design of urban blocks and utilization of solar energy, and also by paying attention to lighting, ventilation, wind direction and building density, up to 50% of energy consumption can be saved [5]. Architects and urban planners have studied the relationship between building form and energy consumption. The relationship between the building and its surrounding environment is an interdisciplinary challenge for architects, urban planners and environmental engineers [6]. Urban planning addresses the impact of urban blocks on the outdoor thermal comfort, and architects examine the effect of the building form on the indoor thermal comfort and building’s energy consumption [7].

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Yamaguchi et al. [8] investigated the impact of form and type of urban block on building energy consumption and concluded that by designing the appropriate form and type of building blocks, the amount of carbon dioxide produced by the buildings can be reduced from 90% to 60%. Vartholomaios [9,10] examined the energy consumption of several types of building forms in the Mediterranean climate by utilizing the Energy Plus software, and revealed that the linear block with the east-west direction was the most suitable mode in order to receive sunlight, and gave the best performance in terms of energy consumption. Taleghani et al. [11] also investigated the impact of residential buildings on energy consumption and lighting in the Netherlands by means of the Design Builder software with respect to simulating the energy and lighting consumption. Hence, by comparing the three forms of single, linear, and central courtyard buildings in the three different modes of one, two, and three-stories, they realized that the central courtyard form was 22% less energy-consuming than the single form building and had 9% lower amounts of discomfort, which is assumed to be the best mode for designing. Studies have shown that using a central courtyard can have a significant impact on reducing energy consumption. Steemers et al. [12] proposed six forms of urban patterns according to the archetype buildings, including pavilions, slabs, terraces, terrace-courts, pavilion-courts and courts. In this study, it was found that the represented forms of the archetype patterns are environmental friendly and are considered to be in line with the lighting criteria. Additionally, it emphasized that the central courtyard has the best performance among the other six archetype patterns. Ratti et al. [13] also did a similar analysis for the central courtyard form in the Moroccan hot climate and pointed out that it could be an optimal form to reduce energy consumption among building forms. In another study, Okeil [14] created a constructional form known as “the solar building block”, and compared it with the two conventional forms, and proposed the energy efficient form, in which the solar residential block had the lowest energy consumption in hot-humid climates at 25 ◦C north latitude. In another study, Yang et al. [15] examined the Bijing’s weather parameters and their effect on the interior comfort of urban blocks. It was observed that the height of the blocks, the thermal mass, the material heat transfer and the surface radiation are important factors in the comfort of the building. The direction of office buildings has a great impact on energy consumption. This was experimentally shown in a study which was conducted in Hashtgerd city, with a hot-dry climate. This study illustrated that expanding the surface of the southern facade of the building by means of increasing the buildings’ direction has a favorable result, however, this action will simultaneously incline the surface of the thermal envelope and inflate the energy waste of the building. Meanwhile, increasing the surface of the southern facade beyond the optimal limit results in receiving energy radiations and the emergence of a heating period, which is not desired or may lead to an increase in absorption of radiant energy during the cooling period. What matters is that this absorption plays a negative role and thus inflates the cooling energy consumption of the building. In addition, the study revealed that the east-west direction has much better performance than the north-south direction in terms of total and primary energy consumption, which usually occurs in most north-south directions [16]. Research conducted in the realm of reducing energy consumption has all been done in order to provide comfort for residents (i.e., supplying light, temperature and ventilation) and with the appropriate design of the building, all studies were able to significantly reduce energy consumption. As mentioned before, office buildings have been assumed to contribute a large part of energy consumption in the construction sector, and yet, no research has been conducted to examine the relation of the form of office buildings to its impact on energy consumption and lighting in the climate of Iran. Accordingly, this study attempts to investigate the below mentioned purposes.

1. A comparison of the four forms of archetype patterns in order to ﬁnd the most appropriate form of ofﬁce building in relation to the cooling, heating, and natural daylight loads for the cold, hot-humid and hot-dry climates of Iran; SustainabilitySustainability 20192019,, 1111,, x 311 FOR PEER REVIEW 33 of of 15 15

2. An investigation of the theory that the suitability of the archetype form with regard to the central 2. An investigation of the theory that the suitability of the archetype form with regard to the central courtyard pattern for buildings [11–13] could be appropriate for buildings with administrative courtyard pattern for buildings [11–13] could be appropriate for buildings with administrative usage in the Iranian climate. usage in the Iranian climate. The first step in designing environmental friendly architecture is to study the climatic factors of the location.The ﬁrst According step in designing to the cluster environmental classification friendly of the architecture coupon, Iran isto has study four the different climatic climates factors includingof the location. hot-humid, According hot-dry, to the cold cluster and classiﬁcationmild-humid [16]. of the In coupon, this research, Iran has the four cities different of Shiraz climates with hot-dryincluding climate, hot-humid, Tabriz hot-dry, with cold cold climate and mild-humid and Bushehr [16 with]. In hot-humid this research, climate the cities were of examined Shiraz with as sampleshot-dry of climate, Iranian Tabriz climates. with cold climate and Bushehr with hot-humid climate were examined as samplesThe ofprevailing Iranian climates.wind in Bushehr, is north-west, with an annual average wind speed of 2.5 m/s, and alsoThe the prevailing annual average wind in temperature Bushehr, is north-west,of Bushehr is with 25 °C. an annualIn addition, average the annual wind speed average of 2.5diffuse m/s, ◦ horizontaland also the solar annual for the average city of temperature Bushehr is 73.3 of Bushehr kWh/m is2 and 25 theC.In annual addition, average theannual of direct average normal diffuse solar 2 forhorizontal this city solaris 95.8 for kWh/m the city2. of Bushehr is 73.3 kWh/m and the annual average of direct normal solar 2 for thisOn citythe isother 95.8 side, kWh/m the prevailing. wind direction in Tabriz is west with an annual average of 3 m/s andOn the otheraverage side, annual the prevailing temperature wind in direction this city in is Tabriz 11.9 is°C, west which with indicates an annual that average building of 3 m/sheating and ◦ isthe a averagecrucial annual point. temperature The annual in thisaverage city is of 11.9 diffuseC, which horizontal indicates thatsolar building for Tabriz heating is is76.2 a crucial kWh/m point.2. 2 Meanwhile,The annual averagethe city of of diffuse Shiraz, horizontal which solaris located for Tabriz in isa 76.2hot-dry kWh/m region. Meanwhile, with an average the city ofannual Shiraz, ◦ temperaturewhich is located of in17.8 ahot-dry °C, has region the prevailing with an average windannual directions temperature of north of and 17.8 north-west,C, has the prevailing and also wind the annualdirections average of north wind and speed north-west, in Shiraz and alsois about the annual 2.2 m/s. average In addition, wind speed the inannual Shiraz average is about 2.2diffuse m/s. 2 horizontalIn addition, solar the annual for Shiraz average is 110.2 diffuse kWh/m horizontal2. Figure solar 1 illustrates for Shiraz isthe 110.2 average kWh/m monthly. Figure temperatures1 illustrates the of theaverage cities monthlyof Tabriz, temperatures Bushehr and of Shiraz the cities through of Tabriz, ten Bushehryears. Tabriz and Shirazhas a cold through climate ten years.in most Tabriz months has ofa coldthe year. climate Bushehr in most possesses months ofthe the highest year. Bushehraverage temperature possesses the almost highest through average all temperature of the months almost of ◦ athrough year, which all of theis between months of15–33 a year, °C, which and Shiraz is between has a 15–33 minimumC, and temperature Shiraz has a of minimum 5.8 °C in temperature January and of ◦ ◦ a5.8 maximumC in January temperature and a maximum of 28.1 °C temperature in July. of 28.1 C in July.

Figure 1. The monthly average temperature of Shiraz, Tabriz and Bushehr cities during the period of Figure 1. The monthly average temperature of Shiraz, Tabriz and Bushehr cities during the period of 2006–2016, cited by Iran Meteorological Organization. 2006–2016, cited by Iran Meteorological Organization. 2. Methodology 2. Methodology In this study, four types of building forms were considered in order to investigate the impact of the formIn this of study, the office four building types of onbuilding the amount forms ofwere cooling considered and heating in order energy to investigate consumption the impact in Shiraz, of theTabriz form and of the Bushehr office [building12,15]. The on formsthe amount are from of cooling archetype and patterns heating whichenergy are consumption among conventional in Shiraz, Tabrizforms ofand office Bushehr buildings [12,15]. [17 The]. According forms are to from Figure archetype2, the first patterns form iswhich singular, are among the second conventional form has formsa central of office courtyard, buildings the third[17]. According form is the to U Figure and the 2, fourth the first form form is is linear. singular, The formsthe second are named form has with a central#A, #B, courtyard, #C and #D the characters, third form respectively. is the U and As the it fo isurth obvious form in is Figurelinear.2 The, the forms first form are named is 1000 with m 2 #A,and #B, #C and #D characters, respectively. As it is obvious in Figure 2, the first form is 1000 m2 and the

Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019, 11, x FOR PEER REVIEW 4 of 15 Sustainability 2019, 11, 311 4 of 15 Sustainability 2019, 11, x FOR PEER REVIEW 4 of 15 next three forms are equally 2000 m2. In order to compare the cooling and heating loads of the buildings,thenext next three three these forms forms values are areequally are equally expressed 2000 2000 m in2 m. Interms2. Inorder order of squareto tocompare compare meters the the(m cooling2 cooling). In this and and research, heating heating four loads loads forms of of theof officebuildings, buildings these these are values values studied are are inexpressed expressed three different in in terms terms modes, of of square square two story,meters meters four (m (m 2story).2 ).In In thisand this research,six research, story modes;four four forms formsthese of areofoffice ofﬁcethe buildings most buildings common are arestudied modes studied in for three in cons three differenttructing different modes,office modes, buildings two story, two [18] story, four. fourstory storyand six and story six modes; story modes; these theseare the are most the common most common modes modes for cons fortructing constructing office ofﬁcebuildings buildings [18]. [18].

FigureFigure 2. 2. DifferentDifferent building building modes: modes: single single form form (#A (#A),), central central yard yard form form ( (#B#B),), U U form form ( (#C#C)) and and linear linear formformFigure ( (#D#D 2.). ).Different building modes: single form (#A), central yard form (#B), U form (#C) and linear form (#D). ForFor the the purpose purpose of of simulating simulating the the energy energy and and natu naturalral lighting lighting of of the the buildings, buildings, the the DesignBuilder DesignBuilder softwaresoftwareFor the[18] [18 purpose] was was utilized. utilized. of simulating The The De DesignBuildersignBuilder the energy and software software natural is is lightingone one of of th theofe themost most buildings, powerful powerful the softwares softwares DesignBuilder in in the the realmrealmsoftware of of simulating[18] simulating was utilized. building building The energy. energy. DesignBuilder Additionally, Additionally, software the the isPlus Plus one Energy Energyof the most Analysis Analysis powerful Engine Engine softwares was was used used in thein in orderorderrealm to toof simulate simulatesimulating the the buildingbuilding building energyenergy. energy and andAdditionally, radiance radiance en enginethegine Plus for for naturalEnergy natural lightAnalysis light analysis. analysis. Engine This This was software software used isin capableisorder capable to of simulate ofconsidering considering the building all allof ofthe energy the detailed detailed and aspectsradiance aspects of en ofthegine the building for building natural and and light for for eachanalysis. each city, city, This with with software different different is climates,climates,capable ofsimulations simulations considering can can all be of conducted the detailed per houraspects throughthro ofugh the variousvarious building timetime and intervals.intervals. for each ForFor city, instance,instance, with different Figure Figure3 3indicatesclimates, indicates simulations the the solar solar graph graph can ofbe of aconducted a six-story six-story building per building hour in thro in Bushehr, Bushehr,ugh various which which time was was intervals. simulated simulated For two two instance, times, times, once Figure once on onJune3 indicates June 21 21 (Summer (Summerthe solar Solstice) Solstice)graph andof anda anothersix-story another timebuilding time on on December in December Bushehr, 21 21 (Winterwhich (Winter was Solstice) Solstice) simulated at at 12:00 two12:00 p.m. times, p.m. Due Dueonce to totheon the June small small 21 difference (Summerdifference between Solstice) between the and the solar another solar graphs graphs time of onof the theDecember studied studied cities, 21 cities, (Winter only only the Solstice) the diagrams diagrams at 12:00 of Bushehrof p.m.Bushehr Due are arerepresentedto therepresented small asdifference samples. as samples. between In order In order the to simulate solar to simulate graphs the selected theof the selected studied forms, forms, at cities, first, at only the first, climate the the diagrams climate data of data theof Bushehr studied of the studiedcitiesare represented were cities collected were as collectedsamples. from the fromIn Meteorological order the toMeteorological simulate Organization the Organizationselected for theforms, period for at the first, of period 2006–2016 the climate of 2006–2016 and data then of and they the thenwerestudied they inputted cities were were into inputted the collected DesignBuilder into from the theDesignBuilder software Meteorological separately software Organization for eachseparately city; for Afterwards, thefor periodeach separatecity;of 2006–2016 Afterwards, EPW filesand separatewerethen createdthey EPW were tofiles ensure inputted were that created into the data thto eensure areDesignBuilder sufficiently that the data valid.software are sufficiently separately valid. for each city; Afterwards, separate EPW files were created to ensure that the data are sufficiently valid.

FigureFigure 3. 3. TheThe studied studied building building in in the the six-story six-story mode mode and and solar solar graphs graphs for for dates dates of of June June 21 21 ( (rightright)) and and DecemberDecemberFigure 3. The21 21 ( (leftstudiedleft)) for for Bushehrbuilding Bushehr (createdin (created the six-story by by DesignBuilder DesignBuilder mode and solarsoftware). software). graphs for dates of June 21 (right) and December 21 (left) for Bushehr (created by DesignBuilder software). InIn addition, addition, in in this this research, research, natural natural ventilation ventilation was was applied applied to to the the software software settings, settings, in in order order to to considerconsiderIn addition, the the movement movement in this ofresearch, of air air based based natural on on the the ventilation heat heat and and cold. cold.was Also,applied Also, during during to the the thesoftware days days of of settings, the the year year in when when order the the to outdooroutdoorconsider weather weatherthe movement is is favorable, favorable, of air naturalbased natural on ventilation ventilation the heat and replaces replaces cold. Also,mechanical mechanical during ventilation, ventilation,the days of and the and yearso so this this when brings brings the thetheoutdoor experiment experiment weather data data is favorable, closer closer to to naturalthe the real real ventilationconditions. conditions. replaces In In all all of ofmechanical the the studied studied ventilation, forms, forms, a a chiller chillerand so is isthis used used brings for for ◦ coolingcoolingthe experiment and and heating. heating. data Forcloser For the the topurpose purposethe real of ofconditions.simulating simulating theIn theall heating heatingof the and studied and cooling cooling forms, set set points,a chiller points, 22 is°C 22 used andCand for24 ◦ °C24cooling baseC base onand ASHRAE on heating. ASHRAE standard, For standard,the purpose respectively, respectively, of simulating were were used the used.. Inheating the In buildings, the and buildings, cooling the surfaceset the points, surface area 22 ofarea °C the and ofglass the 24 forglass°C basethe for outside on the ASHRAE outside facade facadestandard, was wasconsidered respectively, considered to be towere 30%. be 30%.used The. TheIn utilized the utilized buildings, materials materials the insurface in buildings buildings area ofwere were the glassalso also consideredconsideredfor the outside similarly. similarly. facade Accordingly, Accordingly, was considered the the containing containing to be 30%. layers layers The of of utilized the the outsid outside materialse wall, wall, the thein roof,buildings roof, and and the thewere type type also of of glassglassconsidered are are shown shown similarly. in in Table Table Accordingly, 11.. the containing layers of the outside wall, the roof, and the type of glass are shown in Table 1. Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019, 11, x FOR PEER REVIEW 5 of 15 Sustainability 2019, 11, 311 5 of 15

Table 1. Details of utilized materials for simulated buildings in DesignBuilder software. Table 1. Details of utilized materials for simulated buildings in DesignBuilder software. Containing Layer Layer Thickness (mm) R-Value (m2K)/W U-Value W/(m2K) OuterContaining brick layer Layer Layer 100 Thickness (mm) R-Value (m2K)/W U-Value W/(m2K) XPS Expanded Polystyrene 100 Outer wall Outer brick layer 100 2.85 0.35

XPSConcrete Expanded Block Polystyrene100 100 Outer wall 2.85 0.35 GypsumConcrete Plastering Block 10 100 GypsumGypsum plasterboard Plastering 20 10 Inner wall GypsumAir plasterboard10 20 0.61 1.63 Inner wall Gypsum plasterboardAir 20 10 0.61 1.63 GypsumAsphalt plasterboard 10 20 Fiber BoardAsphalt 10 10 Roof XPS ExtrudedFiber Polystyrene Board 40 10 2.09 0.47 Roof XPSConcrete Extruded Polystyrene10 40 2.09 0.47 Concrete 10 Gypsum Plastering 15 Gypsum Plastering 15 Flooring screed 50 Flooring screed 50 Concrete 150 Celling Concrete 150 Celling 0.710.71 1.4 1.4 StandardStandard insulation insulation 30 30 Roof Rooftile tile10 10

3. Data Data Validation Validation InIn order to validate the output data from the DesignBuilder software, and also to ensure the appropriate approachapproach ofof the the problem-solving problem-solving method, method, ﬁrstly, firstly, a similar a similar research research was selected,was selected, in which in whichthe impact the impact of single, of linearsingle, and linear central and courtyard central courtyard forms on theforms heating on the load heating of residential load of buildings residential in buildingsAmsterdam, in Amsterdam, Netherlands, Netherlands, was investigated was investigat [11]. In theed [11]. present In the study, present a central study, two-story a central courtyardtwo-story courtyardform was selectedform was because selected of because the similarity of the ofsimilari the centralty of the courtyard central shapecourtyard with shape the above-mentioned with the above- mentionedstudy in accordance study in accordance with Figure 2with(#B). Figure Then, the2(#B). building Then, wasthe building simulated was along simulated with all along details with in the all detailsDesignBuilder in the DesignBuilder software. software. Figure 44 shows the comparison comparison of of the the building building he heatingating loads loads of ofthe the central central courtyard courtyard form form as the as basethe base mode mode and andas simulated as simulated mode mode in the in DesignBuilder the DesignBuilder software software during during the months the months of the of year. the year.The differenceThe difference between between the measured the measured data data and andthe availabl the availablee data data is 8%, is 8%,which which is an is appropriate an appropriate value, value, so theso the problem-solving problem-solving method method in this in this study study has has been been correctly correctly conducted. conducted.

Figure 4. Comparison of the heating loads of the building of the central courtyard form for the base Figure 4. Comparison of the heating loads of the building of the central courtyard form for the base mode [11] and simulated mode in order to validate the data. mode [11] and simulated mode in order to validate the data.

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4. Results and Discussion Daylight has a crucial role in ofﬁceoffice buildings in terms of energy consumption, lighting, cooling and heating.heating. In In Figure Figure5, the 5, daylightthe daylight is illustrated is illust inrated the four in differentthe four forms.different The forms. radiance The represented radiance byrepresented the DesignBuilder by the DesignBuilder software was software used in orderwas used to analyze in order the todaylight. analyze the Figure daylight.5 shows Figure the daylight 5 shows valuethe daylight at an altitude value at of an 0.75 altitude from the of surface0.75 from of thethe earth,surface which of the is earth, represented which asis therepresented height from as the groundheight from according the ground to the ASHRAEaccording standard. to the ASHRAE As shown standard. in Figure As5, theshown #D formin Figure receives 5, the the #D highest form amountreceives ofthe the highest light, due amount to the of fact the that light, it has due the to largest the fact facade that init thehas south.the largest Also, facade after the in linear the south. form, theAlso, U after form the shape linear possesses form, the the U most form direct shape and possess diffusees the light. most Meanwhile, direct and the diffuse central light. yard Meanwhile, shape has causedthe central the buildingyard shape to receivehas caused direct the light building from the to re outside,ceive direct in addition, light from from the the outside, inside of in the addition, central courtyard,from the inside light of enters the central like it iscourtyard, diffused intolight the ente ofﬁcers like rooms. it is diffused into the office rooms.

Figure 5. TheThe daylight daylight saving saving factor in the studied buil buildings.dings. Models have been analyzed without the monopoly ofof the the sun sun (without (without any obstacleany obstacle in front in of thefront sun) of (createdthe sun) by radiance(created inby the radiance DesignBuilder). in the DesignBuilder). Knowing the shape of the wind ﬂow when it is striking the building, can help us to understand the energyKnowing consumption the shape of of the the wind inside flow of the when building. it is striking When the a part building, of the buildingcan help us is exposedto understand to the windthe energy during consumption cold months, ofit the causes inside an of increase the building. of heat When loss at a thepart walls, of the and building during is the exposed hot months, to the itwind increases during the cold cooling months, load ofit causes the building an increase [19]. Figure of heat6 demonstrates loss at the walls, the shapeand during of the windthe hot ﬂow months, when it meetsincreases the the studied cooling building load of forms the building for different [19]. cities.Figure For 6 demonstrates each individual the city, shape the of wind the wind speed flow and windwhen directionit meets the were studied calculated building with forms the assistance for differen oft numerical cities. For calculations;each individual Accordingly, city, the wind the annual speed averageand wind velocity direction and were prevailing calculated wind with direction the assistance were calculated of numerical too. The calculations; prevailing windAccordingly, direction the in Bushehrannual average is north-west velocity with and a speed prevailing of 2.5 m/s.wind Thedirect prevailingion were wind calculated for Shiraz too. is The also prevailing north-west wind with adirection speed of in 2.2 Bushehr m/s and is for north-west Tabriz the with prevailing a speed wind of 2.5 direction m/s. The is west prevailing with an wind average for speed Shiraz of is 3 m/s.also north-westAs indicated with a in speed Figure of6 ,2.2 in them/s cities and offor Bushehr Tabriz the and prevailing Shiraz, the wind northern direction and westernis west facadeswith an ofaverage the buildings speed of which 3 m/s. are exposed to the wind, cause the areas located in the north and west of the buildingAs indicated to consume in moreFigure energy 6, in the through cities theof Bu coldshehr months. and Shiraz, This is the due northern to heat that and is western wasted throughfacades theof the walls. buildings Besides, which during are summer, exposed into periods the wind, where cause the the weather areas located is mild, in wind the cannorth be and used west as natural of the ventilationbuilding to forconsume the building, more energy and in through hot seasons the cold when mont thehs. air This temperature is due to heat is higher that is than wasted comfortable, through the walls. Besides, during summer, in periods where the weather is mild, wind can be used as natural

Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019,, 1111,, 311x FOR PEER REVIEW 7 of 15 ventilation for the building, and in hot seasons when the air temperature is higher than comfortable, it cancan increaseincrease thethe coolingcooling load of the northern and western areas. In In addition, addition, the the west west wind wind flow, ﬂow, which has exposed the building forms in Tabriz, hashas resultedresulted inin heatheat lossloss of the inside of the building for the western areasareas throughthrough thethe coldcold monthsmonths ofof thethe year.year.

Figure 6. Pattern ofof thethe windwind ﬂowflow aroundaround the the four four building building forms forms based based on on the the average average wind wind speed speed of Bushehrof Bushehr (2.5 (2.5 m/s), m/s), Shiraz Shiraz (2.2 (2.2 m/s) m/s) and and Tabriz Tabriz (3 (3 m/s) m/s) (created (created by by DesignBuilder). DesignBuilder).

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TheThe annual annual heating heating consumption consumption of ofoffice ofﬁce buildings buildings in Bushehr in Bushehr are areillustrated illustrated in Figure in Figure 7. As7. shownAs shown in Figure in Figure 7, the7, the lowest lowest annual annual heating heating consumption consumption amongst amongst the the building building forms forms of of two, two, four four andand six six stories stories belongs toto thethe linearlinear form; form; this this is is because because it it has has the the highest highest light light gain gain in thein the northern northern and andsouthern southern facades facades (Figure (Figure5) and 5) additionally, and additionally, the exterior the exterior surfaces surfaces of the building of the building are more are exposed more exposedto the sun. to the In sun. the secondIn the second place afterplace the after linear the linear form, form, the single the single form form has the has lowest the lowest heating heating load. load.This This is also is also because because all ofall theof the areas areas which which are are receiving receiving light light from from allall around,around, and, the the daylight, daylight, inin turn, turn, helps helps the the indoor indoor environment environment to to be be wa warmedrmed up. up. Meanwhile, Meanwhile, the the outer outer surfaces surfaces are are more more exposedexposed to to sun sun rather rather than than the the U U form form or or the the ce centralntral courtyard courtyard form form and and thus thus have have less less shadowing shadowing onon the the outer outer surfaces. surfaces. The The two two forms forms of of the the centra centrall courtyard courtyard form form and and the the U U form form have have almost almost the the samesame consumption consumption and and possess possess almost almost 25% 25% more more en energyergy consumption consumption from from the the aspect aspect of of heating heating in in comparisoncomparison to to the the linear linear form. form. TheThe annual annual cooling cooling consumption consumption of ofthe the office ofﬁce buildings buildings of Bushehr of Bushehr is illustrated is illustrated in Figure in Figure 8. As8. shownAs shown in Figure in Figure 8, the8, the linear linear form form among among the the ot otherher forms forms of of the the two-story two-story modes, modes, has has the the lowest energyenergy consumption consumption from from the the aspect aspect of of cooling cooling load, load, and and then then the the central central courtyard courtyard form, form, the the single single formform and and the the U U form form have have the the lowest energy consumptions, respectively. respectively. In In four-story four-story building building mode,mode, the the lowest lowest energy energy consumption consumption for for cooling cooling load load belongs belongs to to the the linear linear form, form, central central yard yard form, form, UU form form and and single single form. form. In In the the six-story six-story mode, mode, the the central central courtyard courtyard form form has has the the least least energy energy consumptionconsumption from from the the aspect aspect of ofcooling cooling load, load, and and then then there there take take place place the linear the linear form, form, U form, U form,and singleand single form, form, respectively. respectively. TheThe total coolingcooling andand heating heating loads loads per per square square meter, meter, for allfor building all building forms forms in Bushehr in Bushehr are shown are shownin Figure in 9Figure. According 9. According to Figure to9 ,Figure among 9, the among building the formsbuilding through forms the through two-story the two-story modes, the modes, linear theform linear has form the lowest has the energy lowest consumption, energy consumption, and then theand central then the courtyard central courtyard form, single form, form single and form the U andform, the in U ascending form, in ascending order. Among order. the Among four-story the buildingfour-story forms, building the energyforms, consumptionthe energy consumption from lowest fromto the lowest highest to belongs the highest to the belongs linear form,to the the linear central form, courtyard the central form courtyard and the U form form. and Additionally the U form. for Additionallythe six-story for building, the six-story the central building, courtyard the central form courtyard has the least form energy has the consumption least energy and consumption afterwards andfrom afterwards lowest to thefrom highest, lowest isto the the linear highest, form, is the the linear U form form, and the the U single form form. and the single form. FigureFigure 10 10 shows shows the the normal normal daylight daylight amount amount of of all all building building forms forms for for Bushehr Bushehr during during the the year. year. AccordingAccording to to Figure Figure 10,10, the the linear linear form form in in all all of of the the three three modes modes of of two, two, four four and and six-story six-story buildings buildings hashas the the highest highest amount amount of of daylight daylight;; this this is is due due to to the the largest largest surf surfaceace which which belongs belongs to to the the north north and and southsouth facades facades where itit receivesreceives the the most most amount amount of of sunlight sunlight (Figure (Figure5). The5). The U form U form and theand single the single form formreceive receive approximately approximately 15% lower 15% amountslower amounts of daylight of daylight than the than linear the form linear and form the centraland the courtyard central courtyardform also form receives also 39% receives lower 39% amounts lower ofamounts natural of daylight natural than daylight the linear than form.the linear form.

FigureFigure 7. 7. AverageAverage heating heating load load of of the the building building forms forms which which were were studied studied during during a a year, year, Bushehr. Bushehr.

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Figure 8. Average cooling load of the studied building forms during a year in Bushehr. Figure 8. Average cooling load of the studied building forms during a year in Bushehr. Figure 8. Average cooling load of the studied building forms during a year in Bushehr.

FigureFigure 9.9. The average total total cooling cooling and and heating heating load load of of th thee studied studied building building forms forms during during the the year year in Figure 9. The average total cooling and heating load of the studied building forms during the year in inBushehr. Bushehr. Bushehr.

Figure 10. Average daylight factor for all of the buildingilding formsforms duringduring thethe yearyear inin Bushehr.Bushehr. Figure 10. AverageAverage daylight factor for all of the buildingbuilding forms during the year in Bushehr.

FigureFigure 1111 demonstratesdemonstrates thethe annualannual amountamount ofof heatingheating perper squaresquare metermeter forfor allall ofof thethe buildingbuilding Figure 11 demonstrates the annual amount of heating per square meter for all of the building formsforms inin Shiraz.Shiraz. AsAs shownshown in in Figure Figure 11 11,, the the linear linear form form has has the the least least heating heating consumption, consumption, and and next next is forms in Shiraz. As shown in Figure 11, the linear form has the least heating consumption, and next theisis thethe single singlesingle form, form,form, the thethe U UU form formform and andand the thethe central centralcentral courtyard courtyardcourtyard form, form,form, from fromfrom lowest lowestlowest to toto thethethe highesthighest consumption. consumption. is the single form, the U form and the central courtyard form, from lowest to the highest consumption.

Sustainability 2019,, 11,, x;x; doi:doi: FORFOR PEERPEER REVIEWREVIEW www. www.mdpi.com/journal/sustainability/sustainability Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019, 11, x FOR PEER REVIEW 10 of 15 Sustainability 2019,, 11,, x 311 FOR PEER REVIEW 1010 of of 15 15 The reason for the low consumption of heating regarding the linear form is because the outer surfaces The reason for the low consumption of heating regarding the linear form is because the outer surfaces are more exposed to the sun in comparison with the other forms (Figures 3 and 5). areThe more reason exposed for the to low the consumption sun in comparison of heating with regarding the other the forms linear (Figures form is 3 becauseand 5). the outer surfaces Figure 12 shows the amount of cooling energy consumption per square meter for all building are moreFigure exposed 12 shows to the the sun amount in comparison of cooling with energy the otherconsumption forms (Figures per square3 and meter5). for all building forms in Shiraz. According to Figure 12, the central yard form in the two, four and six-story modes formsFigure in Shiraz. 12 shows According the amount to Figure of cooling 12, the energy centra consumptionl yard form perin the square two, meter four and for all six-story building modes forms has the lowest energy consumption. Because the central yard form creates the most shading on the hasin Shiraz. the lowest According energy to consumption. Figure 12, the Because central yardthe ce formntral inyard the form two, fourcreates and the six-story most shading modes hason the the outer surfaces (Figure 3), the light inside the central courtyard enters the building`s zones in a diffuse outerlowest surfaces energy consumption.(Figure 3), the Because light inside the central the central yard formcourtyard creates enters the most the building`s shading on zones the outer in a surfacesdiffuse way (Figure 5). The amount of energy for the cooling purposes are equal both in the linear and the U way(Figure (Figure3), the 5). light The inside amount the of central energy courtyard for the coolin entersg purposes the building’s are equal zones both in a in diffuse the linear way (Figureand the5 U). form modes for the two-story buildings. In addition, the single form has the maximum energy formThe amount modes offor energy the two-story for the cooling buildings. purposes In ad aredition, equal the both single in the form linear has and the the maximum U form modes energy for consumption through all modes, because the minimum shading is applied on the outer surfaces of consumptionthe two-story buildings.through all In modes, addition, because the single the formminimum has the shading maximum is applied energy on consumption the outer surfaces through allof the building (Figure 5). themodes, building because (Figure the minimum 5). shading is applied on the outer surfaces of the building (Figure5). Figure 13 shows the total average of heating and cooling per square meter for all forms during Figure 13 shows the total average of heating and cooling per per square meter for all forms during a year in Shiraz. According to Figure 13, the central yard form has the least energy consumption in a year in Shiraz. According According to to Figure Figure 13,13, the central yard form has the least energy consumption in all modes. In terms of energy consumption, after the central courtyard form is the U form, linear form all modes. modes. In In terms terms of of energy energy consum consumption,ption, after after the the central central courtyard courtyard form is the U U form, form, linear linear form form and single form, from the lowest amount of consumption to the highest amount. Among the forms and single form, fromfrom thethe lowestlowest amountamount of of consumption consumption to to the the highest highest amount. amount. Among Among the the forms forms in in the two-story buildings, the linear form consumes 6% more energy than the courtyard form and inthe the two-story two-story buildings, buildings, the the linear linear form form consumes consum 6%es 6% more more energy energy than than the courtyardthe courtyard form form and and also also the U form consumes 7% more energy in comparison with the central courtyard form, and finally alsothe Uthe form U form consumes consumes 7% more7% more energy energy in comparison in comparison with with the the central central courtyard courtyard form, form, and and ﬁnally finally the the single form consumes 9% more energy than the central courtyard form. thesingle single form form consumes consumes 9% 9% more more energy energy than than the centralthe central courtyard courtyard form. form. Figure 14 demonstrates the average amounts of natural daylight through all forms of buildings Figure 14 demonstrates thethe averageaverage amountsamounts of of natural natural daylight daylight through through all all forms forms of of buildings buildings in in Shiraz during a year. According to Figure 14, the linear form has the most daylight among all forms inShiraz Shiraz during during ayear. a year. According According to to Figure Figure 14 ,14, the the linear linear form form has has the the most most daylight daylight among among all all forms forms of of buildings, because it has the highest surface in the north and south facades and receives the highest ofbuildings, buildings, because because it it has has the the highest highest surface surface in in the the north north and and southsouth facadesfacades andand receives the highest amounts of sunlight (Figure 5). The U form and single form receive approximately 16% lower amounts ofof sunlightsunlight (Figure (Figure5). 5). The The U form U form and singleand single form receiveform receive approximately approximately 16% lower 16% amounts lower amounts of light than the linear form, and the central yard form receives 39% lower amounts of amountsof light than of light the linear than form,the linear and the form, central and yard the formcentral receives yard 39%form lower receives amounts 39% lower of normal amounts daylight of normal daylight in comparison with the linear form. normalin comparison daylight with in comparison the linear form. with the linear form.

Figure 11. Total average amounts of heating loads for the studied building forms during a year in Figure 11. 11. TotalTotal average average amounts amounts of of heating heating loads loads for for th thee studied studied building building forms forms during during a year a year in Shiraz. Shiraz.in Shiraz.

Figure 12.12. TotalTotal amounts amounts of of average average cooling cooling loads loads of the of studiedthe studied building building forms forms during during a year ina year Shiraz. in Figure 12. Total amounts of average cooling loads of the studied building forms during a year in Shiraz. Shiraz.

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FigureFigure 13.13. Total amounts of cooling cooling and and heating heating loads loads of of the the studied studied building building forms forms during during a year a year in Figure 13. Total amounts of cooling and heating loads of the studied building forms during a year in inShiraz. Shiraz. Shiraz.

FigureFigure 14.14. The average dayday lightlight factorfactor ofof thethe studiedstudied buildingbuilding formsforms duringduring aa yearyear inin Shiraz.Shiraz. Figure 14. The average day light factor of the studied building forms during a year in Shiraz. FigureFigure 1515 illustratesillustrates thethe averageaverage heatingheating energy perper square meter regarding thethe forms for Tabriz Figure 15 illustrates the average heating energy per square meter regarding the forms for Tabriz duringduring aa year.year. As shown in Figure 1515,, the single formform andand centralcentral courtyardcourtyard formform inin allall modesmodes during a year. As shown in Figure 15, the single form and central courtyard form in all modes consumedconsumed thethe leastleast amountamount ofof energyenergy forfor heating.heating. ThisThis isis becausebecause theythey havehave thethe highesthighest amountsamounts ofof consumed the least amount of energy for heating. This is because they have the highest amounts of exteriorexterior exposureexposure to to sunlight. sunlight. The The other other forms, forms, from from the lowest the lowest to the highest,to the arehighest, the central are the courtyard central exterior exposure to sunlight. The other forms, from the lowest to the highest, are the central formcourtyard and the form U form.and the U form. courtyard form and the U form. InIn FigureFigure 1616,, the average average energy energy required required for for cooling cooling of of the the studied studied forms forms is isshown shown in inTabriz Tabriz in In Figure 16, the average energy required for cooling of the studied forms is shown in Tabriz in inper per square square meters. meters. Figure Figure 16 16 demonstrates demonstrates that that the the central central courtyard courtyard form form has has the leastleast energyenergy per square meters. Figure 16 demonstrates that the central courtyard form has the least energy consumptionconsumption inin all all modes, modes, because because the the central central courtyard courtyard form form implies implies the most the shading most shading on the exterior on the consumption in all modes, because the central courtyard form implies the most shading on the surfacesexterior ofsurfaces the building of the (Figurebuilding3), (Figure and the 3), single and formthe single has the form highest has the energy highest consumption energy consumption because it exterior surfaces of the building (Figure 3), and the single form has the highest energy consumption hasbecause the lowest it has shadowingthe lowest shadowing at the outer at surfaces the outer (Figure surfaces3). The(Figure two-story 3). The linear two-story form linear has the form lowest has because it has the lowest shadowing at the outer surfaces (Figure 3). The two-story linear form has energythe lowest consumption energy consumption after the central after courtyardthe central form. courtyard The U form. form The in the U form four andin the six-story four and modes six-story has the lowest energy consumption after the central courtyard form. The U form in the four and six-story themodes lowest has energythe lowest consumption energy consumption after the central after courtyardthe central form. courtyard form. modes has the lowest energy consumption after the central courtyard form. FigureFigure 1717 illustratesillustrates thethe totaltotal averageaverage monthlymonthly energyenergy consumptionconsumption forfor thethe coolingcooling andand heatingheating Figure 17 illustrates the total average monthly energy consumption for the cooling and heating loadsloads inin TabrizTabriz through through all all of of the the simulation simulation modes. mode Accordings. According to Figureto Figure 17, 17, the the central central yard yard form form has loads in Tabriz through all of the simulation modes. According to Figure 17, the central yard form thehas lowestthe lowest energy energy consumption, consumption, followed followed by the by linear the linear form, singleform, single form and form U form,and U from form, the from lowest the has the lowest energy consumption, followed by the linear form, single form and U form, from the amountslowest amounts of consumption of consumption to the highest to the highest amounts amounts of consumption. of consumption. lowest amounts of consumption to the highest amounts of consumption.

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Figure 15. The average heating load for building forms during a year in Tabriz. Figure 15. The average heating load for building forms during a year in Tabriz. FigureFigure 15. 15. TheThe average average heating heating load load for for building building forms forms during a year in Tabriz.

Figure 16. The average cooling loads for building forms during a year in Tabriz. Figure 16. The average cooling loads for buildingbuilding forms during a year in Tabriz. Figure 16. The average cooling loads for building forms during a year in Tabriz.

FigureFigure 17. 17. TheThe total total average average cooling cooling and and heating heating loads loads of of the the building building forms forms in in Tabriz Tabriz during a year. Figure 17. The total average cooling and heating loads of the building forms in Tabriz during a year. Figure 17. The total average cooling and heating loads of the building forms in Tabriz during a year. Figure 18 shows the average amount of natural daylight among all building forms in Tabriz during Figure 18 shows the average amount of natural daylight among all building forms in Tabriz the year.Figure According 18 shows to Figurethe average 18, the amount linear form of natural receives daylight the maximum among natural all building light due forms to the in fact Tabriz that duringFigure the year. 18 shows According the average to Figure amount 18, the of linear natural form daylight receives among the maxi all mumbuilding natural forms light in Tabrizdue to theduring highest the year. external According surface ofto theFigure building 18, the is linear on the form southern receives facade, the maxi and itsmum east-west natural direction light due has to duringthe fact thethat year. the highestAccording external to Figure surface 18, ofthe the linear building form isreceives on the thesouthern maximum facade, natural and itslight east-west due to resultedthe fact that in the the highest highest amounts external of surface light (Figure of the5 ),bu andilding inall is cases,on the the southern central facade, courtyard and form its east-west receives thedirection fact that has the resulted highest in externalthe highest surface amounts of the of bulightilding (Figure is on 5), the and southern in all cases, facade, the centraland its courtyardeast-west thedirection lowest has amounts resulted of in light. the Meanwhile,highest amounts among of light the two-story (Figure 5), buildings, and in all after cases, the the linear central form courtyard is the U directionform receives has resulted the lowest in theamounts highest of amountslight. Meanwhile, of light (Figure among 5), the and two-story in all cases, buildings, the central after courtyard the linear form receives the lowest amounts of light. Meanwhile, among the two-story buildings, after the linear form receives the lowest amounts of light. Meanwhile, among the two-story buildings, after the linear Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019, 11, x; doi: FOR PEER REVIEW www.mdpi.com/journal/sustainability Sustainability 2019, 11, 311 13 of 15 Sustainability 2019, 11, x FOR PEER REVIEW 13 of 15 form andis the the U singleform and form, the from single the form, aspect from of obtaining the aspect more of obtaining light and thusmore more light decent and thus functions. more decent In the functions.four-story buildings,In the four-story the U form buildings, gains 4% the more U form lighting gains than 4% the more linear lighting form. In than addition, the linear in the form. six-story In addition,building, thein the single six-story form receivesbuilding, 8% the more single natural form daylightreceives than8% more the U natural form. daylight than the U form.

FigureFigure 18. 18. TheThe average average daylight daylight factor factor of of the the bu buildingilding forms in Tabriz during a year.

5. Conclusions 5. Conclusions In this research, four different archetype patterns (single form, central courtyard form, U form In this research, four different archetype patterns (single form, central courtyard form, U form and linear form) were investigated in the two, four, and six-story building modes with the office and linear form) were investigated in the two, four, and six-story building modes with the office usage, in order to determine the most appropriate form of office building from the aspect of examining usage, in order to determine the most appropriate form of office building from the aspect of cooling, heating and natural daylight for the cold, hot-humid and hot-dry regions of Iran. In addition, examining cooling, heating and natural daylight for the cold, hot-humid and hot-dry regions of Iran. a theory of the suitability of the archetype pattern for the central courtyard form with respect to energy In addition, a theory of the suitability of the archetype pattern for the central courtyard form with and lighting consumption for office buildings [11–13] in the hot-humid climate of Bushehr, hot-dry respect to energy and lighting consumption for office buildings [11–13] in the hot-humid climate of climate of Shiraz and cold climate of Tabriz, was determined. The conducted calculations approved Bushehr, hot-dry climate of Shiraz and cold climate of Tabriz, was determined. The conducted that the archetype patterns are suitable to be applied, especially on the central courtyard form, from calculations approved that the archetype patterns are suitable to be applied, especially on the central the perspective of energy consumption, which was investigated in the cities of Shiraz with hot-dry courtyard form, from the perspective of energy consumption, which was investigated in the cities of climate and Tabriz with cold climate. It is somehow different for the hot-humid climate of Bushehr as Shiraz with hot-dry climate and Tabriz with cold climate. It is somehow different for the hot-humid the central courtyard form does not show a suitable performance in terms of lighting. The summarized climate of Bushehr as the central courtyard form does not show a suitable performance in terms of results are represented specifically for each city below: lighting. The summarized results are represented specifically for each city below: 1. Among the two-story building modes, the linear form has the least energy consumption, and then 1. Among the two-story building modes, the linear form has the least energy consumption, and the central courtyard form, the single form and the U form. Additionally, among the four-story then the central courtyard form, the single form and the U form. Additionally, among the four- building modes, the linear form, the central courtyard form, the U form and the single form story building modes, the linear form, the central courtyard form, the U form and the single form have the least to the most energy consumptions, respectively. For the six-story building mode, have the least to the most energy consumptions, respectively. For the six-story building mode, the central courtyard form has the least energy consumption and subsequently, from the least to the central courtyard form has the least energy consumption and subsequently, from the least to most amount of consumption, is the U form and the single form. The U form and the single form most amount of consumption, is the U form and the single form. The U form and the single form receive approximately 15% lower amounts of daylight in comparison to the linear form, and the receive approximately 15% lower amounts of daylight in comparison to the linear form, and the courtyard form receives 39% lower amounts of natural daylight in comparison to the linear form. courtyard form receives 39% lower amounts of natural daylight in comparison to the linear form. 2. In Shiraz, the central courtyard form has the least energy consumption through all modes. 2. In Shiraz, the central courtyard form has the least energy consumption through all modes. In In terms of energy consumption, after the central courtyard form is the U form, the linear terms of energy consumption, after the central courtyard form is the U form, the linear form and form and single form, from least to most energy consumption. In terms of receiving natural single form, from least to most energy consumption. In terms of receiving natural daylight, the daylight, the linear form has the highest amounts of daylight among all the other building forms. linear form has the highest amounts of daylight among all the other building forms. The U form The U form and single form receive approximately 16% lower amounts of lighting than the linear and single form receive approximately 16% lower amounts of lighting than the linear form, and form, and the central courtyard form receives 39% lower amounts of natural daylight than the the central courtyard form receives 39% lower amounts of natural daylight than the linear form. linear form. 3. In the city of Tabriz, among all of the building modes, the central courtyard form has the lowest 3. energyIn the cityconsumption, of Tabriz, and among afterwards, all of the in order building from modes, least to the most, central is the courtyard linear form, form the has single the form,lowest and energy the U consumption, form. In terms and of afterwards,natural daylight, in order the fromlinear least form to receives most, is the the most linear natural form, daylight through all modes, and the central courtyard form receives the minimum amount of

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the single form, and the U form. In terms of natural daylight, the linear form receives the most natural daylight through all modes, and the central courtyard form receives the minimum amount of lighting through other modes. Among the two-story building modes, after the linear form, the U form and the single form have decent function in terms of obtaining more lighting. In the four-story building modes, the U form receives 4% more lighting than the linear form, and additionally for the six-story building modes, the single form receives 8% more natural daylight in comparison with the U form.

By the numerical analysis and the direction of the wind flow regarding its collision with the building forms, it is concluded that for the cities of Bushehr and Shiraz, the northern and western building facades are exposed to wind flow. This, in turn, causes heat loss through the walls at the northern and western areas of the building during the cold months and thus more heating energy is consumed. Meanwhile, in the summer season, when the air temperature is mild, the wind flow can be used as natural ventilation for the building. In addition, in the hot seasons where the air temperature is higher than the comfort level, it increases the cooling load at the northern and western parts of the building. Finally, the west wind flow which is blown at the building forms in Tabriz, results in heat loss of the inside of the building at the western areas through the cold months of the year. This study shows that understanding vernacular patterns and traditional architecture could be an effective way in sustainable design and energy consumption. There are many patterns in building physics that could be revised and upgraded to reuse and reorganize in modern architecture.

Author Contributions: J.S.: Designed and performed experiments, analyzed data, developed the theory, performed the computations and wrote the paper. M.Y.: make substantial contributions interpretation of data and supervised the findings of this work. A.H.: participate in drafting the article and revising it critically for important intellectual content, verified the analytical methods and supervised the findings of this work. A.C.: make substantial contributions to conception and design, and acquisition of data, performed the analytic calculations and performed the numerical simulations and co-wrote the paper. All authors give final approval of the version to be submitted and revised version and final manuscript. Funding: This work was supported by the German Research Foundation (DFG) and the Technical University of Munich (TUM) in the framework of the Open Access Publishing Program. Conﬂicts of Interest: The authors declare no conﬂict of interest.

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