Development of Quality Control Requirements for Improving the Quality of Architectural Design Based on BIM

applied sciences

Article Development of Quality Control Requirements for Improving the Quality of Architectural Design Based on BIM

Jungsik Choi 1 , Sejin Lee 2 and Inhan Kim 2,*

1 Architecture IT Convergence Engineering, Division of Smart Convergence Engineering, Hanyang University, Ansan-Si 15588, Korea; [email protected] 2 Department of Architecture, Kyung Hee University, Yongin-si 17104, Korea; [email protected] * Correspondence: [email protected]; Tel.: +82-31-201-2926

Received: 11 August 2020; Accepted: 4 October 2020; Published: 12 October 2020

Abstract: Building information modeling (BIM) technology has been utilized increasingly in quantitative ways in the architecture, engineering, and construction disciplines. However, owing to increasing requirements for improvement in qualitative factors in BIM-based design projects, it has become necessary to develop a checking and evaluation process for BIM-based architectural design. The purpose of this study is to develop and apply BIM-based quality control requirements for improving the quality of architectural design. To achieve this, the research investigated case studies for BIM data quality control and classified quality control targets according to physical/logical quality and data quality. The quality check criteria and checklists are developed through the reconfiguration of deduced quality control targets by requirement. The research developed a rule-based quality checking system using requirements for efficient quality control based on BIM.

Keywords: building information modeling (BIM); industry foundation classes (IFC); quality control requirements; quality check criteria; rule-based quality checking system

1. Introduction The construction industry relies on a vast array of architectural information, as an architectural process includes a variety of design stages and the cooperation of many disciplines. In particular, architectural information is generated and managed throughout the life of a building, from the conceptual design stage to construction and maintenance [1]. Building information modeling (BIM) technology improves the productivity and efficiency of the construction industry by taking advantage of the information generated throughout the life cycle of the facility to build a consistent system to maximize production efficiency and utilization of information [2]. BIM has actively been adopted to support the productivity of the construction industry. Further, public institutions in advanced countries (e.g., the United States [US], United Kingdom, Singapore, and South Korea) have mandated the implementation of BIM in design delivery, and promote automated checking for BIM quality [3]. This has a strong influence by promoting practices that use BIM. Improvements in work efficiency and productivity occur as a result of BIM adoption, depending on the consistency and accuracy of data [4]. The purpose of quality control in construction work is to ensure a structure is built in a rational, economical, and durable way. Improvement in quality reliability and reduction in costs can be achieved by securing a certain quality, improving quality and maintaining constant quality in the overall project [5]. Therefore, quality control is a very important factor in terms of project management. Quality control requirements are included in the BIM guidelines of some countries (e.g., Finland, USA, and Denmark). However, requirements for quality control

Appl. Sci. 2020, 10, 7074; doi:10.3390/app10207074 www.mdpi.com/journal/applsci Appl. Sci. 2020, 10, 7074 2 of 25 are insufficiently detailed in current general BIM guidelines. There are limitations in adopting these guidelines into detailed work practices [6,7]. BIM technology has been utilized increasingly in quantitative ways in the architecture, engineering, and construction (AEC) disciplines. Owing to recently increased requirements for the improvement of qualitative factors in BIM-based design projects, various quality checks are performed using BIM-based checking software. However, there are problems with this, such as a lack of BIM-based evaluation requirements [8]—reflecting the design changes that occur continually in the design phase [2,9]—and a lack of automated quality check processes through quality checking systems [10–12]. Therefore, it is necessary to define the checking and evaluation process and develop checking software for quality improvements to a BIM-based architectural design model. The purpose of this study is to develop and apply quality check control requirements for improving the quality of architectural design based on BIM. To achieve this, the study defined quality check targets for the BIM-based design phase by analyzing the work and output information of each stage of the architectural design process and extracting detailed quality check targets from status (e.g., BIM guidelines, rule-based quality checking software) and domestic regulations. In addition, the research developed quality check requirements consisting of space check criteria, design check criteria and construction check criteria according to the nature and purpose of the work. Finally, the research developed a rule-based quality checking system using requirements for efficient quality controls based on BIM. The quality check requirements, which consist of classified targets to be considered when creating and assessing BIM data by designer and evaluator, could become necessary for common works in the design process. Therefore, an improvement in design quality could be expected when these quality control requirements are actively utilized. The methodology employed in this study is as follows:

The applied design phase was deﬁned by analyzing the work and output information for each • stage in the design process. Quality check targets were deduced through advanced practices (e.g., guidelines, software) and • domestic regulations. Quality check requirements consisting of a space check, design check, and construction check • were developed by categorizing the subject of the quality control according to the object and purpose of the works. Regulation checking is included in the design check criteria. A process of deﬁnition and development of element technologies was suggested for applying • quality control to architectural design based on BIM. The results of quality checks were validated using rule-based quality checking software.

2. Literature Review

2.1. Overview of BIM-Based Quality Control A building information model is a digital representation of the physical and functional characteristics of a facility. As such, it serves as a shared knowledge resource for information about a facility, forming a reliable basis for decisions during its life cycle, from inception onward [13]. As stages in the architectural process proceed, information is added and merged continuously. BIM applies parametric technology, where intelligent building objects can represent the geometric information, spatial relationships, geographic information, quantities and properties of building objects, material inventories and project schedules [14,15]. In paticular, BIM is useful for quality control using building object properties such as characteristic and relation information for various disciplines. As an aspect of BIM, quality control encourages correct utilization of data, and quality checks review the validity of the physical and logical information to increase productivity. Quality control requirements based on BIM according to the goals and objectives of quality checks can be classiﬁed as shown in Table1[16]. Appl. Sci. 2020, 10, 7074 3 of 25

Table 1. Classiﬁcation of quality control based on building information modeling (BIM).

Classiﬁcation Description

Adequacy requirements for model shape • - Minimum requirements for Physical information quality shape representation - Suitability of model location - Clash check of space model

Adequacy requirements for model logic • Logical information quality - Requirements check based on regulations - Path analysis of components/space for evacuation

Adequacy requirements for model data • Data quality - Representation check of components - Checking properties of input data - Checking space program

BIM has been actively adopted in the construction industry because of an awareness of the importance of utilizing and assessing design information. However, there are problems with current quality control:

It is difficult to define the information to be delivered to each subsequent stage in the design phase • and to utilize the delivered information at the next stage; due to the lack of definition of the work and requirements for each design stage [17]. Design information quality control should be performed continuously to reflect the design changes • that occur throughout the design phase. However, immediate reflection is typically not performed properly because requirements and software for quality control are lacking [2,11]. As a construction project progresses, the amount of information that must be analyzed and • checked increases. Most regulation checking is still performed manually, which is error-prone and reduces work efficiency [3,10,18,19]. The lack of requirements and guidelines related to BIM degrades design quality. Although some • BIM guidelines include quality control requirements, there is a lack of detailed requirements for quality control in such guidelines. Further, there are limitations with the guidelines to be adopted in quality control work practices [4,9,20].

2.2. The Status of Guidelines for Quality Control Many governments have been developing BIM guidelines for various sectors to institute the adoption of BIM. Some BIM guidelines deal with quality control either directly or indirectly. Although some aspects of quality control are included, the exact scope and content of quality control is still insuﬃcient. Table2 provides a summary of the various aspects of quality control in the BIM guidelines dealing with quality control. Appl. Sci. 2020, 10, 7074 4 of 25

Table 2. The status and content of BIM-based guidelines for quality control.

Guidelines Purpose Main Content

Spatial BIM: check on location and property of • space, and whether it reﬂects the space program Architectural BIM: check on the interference • Provide BIM guidelines to between objects or dual representation of • improve business decision building elements making in the design and Structural BIM: check on the interference Common BIM requirements 2012 • (Finland) [21] construction process between architectural and structural objects and Create a checklist for the suitable location for objects • each stage System BIM: check on the interference between • HVAC, electrical, and architectural objects Merged BIM: check on the suitable location and • interference between objects in various BIMs

3D Constructability check • • implementation methodology Deﬁne the factors (e.g., object, geometric data, 3D CAD manual 2006 • Representation of rules property, and simulation) to be included in the (Denmark) [22] • and guidelines quality check

Spatial program validation: provide BIM • Manage design quality and guidelines for modeling space and each object • U.S. General Services construction requirements to check space Administration (GSA) BIM guide Provide BIM guidelines by Energy performance: deﬁne and apply the • • series (USA) [23] applied sector building elements required for energy simulation

Quality check on BIM (validation of a set of Presentation of the • • elements, visual veriﬁcation, AEC CADD US Army Corps of Engineers long-term roadmap standards compliance) (USACE) BIM roadmap (USA) [24] Details are not deﬁned • Structural analysis, cost estimates •

Criteria for Norwegian Check the format and properties of • • government building projects model elements over a certain size Statsbygg BIM manual Visualization check Includes the evaluation of • (Norway) [25] • Space check (e.g., area calculations, validation) alternatives, and • Energy analysis ﬁnancial evaluation •

Quality check of BIM data model for projects • Provide common applying BIM should be conducted • requirements for adoption Provides a kind of BIM quality assurance, • BIM application guide in and application of open BIM quality criteria for BIM, methods of quality construction sector (Korea) [26] in the domestic design assurance, a data format used in quality sector [27] assurance, and range of responsibilities in BIM quality

Develop design requirements BIM design quality check in the • • Design competition guidelines for and guidelines based on pre-qualiﬁcation stage open BIM [27] Space requirements assessment power exchange headquarters • Provide BIM basic quality assessment project (Korea) [28] • • pre-assessment management Energy performance assessment •

Develop roadmap and guidelines for business • Develop roadmap and facility BIM applications BIM guidelines for the Public • guidelines for business Develop BIM management guidelines (for PPS, Procurement Service (PPS) • (Korea) [29] facility BIM applications demand institutions), BIM data guide and BIM data delivery guide (for contractors) Appl. Sci. 2020, 10, 7074 5 of 25

2.3. The Status of Quality Control Software Quality control software that is rule-based is able to perform an accurate and detailed clash check of physical BIMs. Navisworks and the Solibri Model Checker (SMC) are two leading software programs in the construction industry that can check model quality based on BIM. Navisworks has strengths in 4D and can only perform physical checks such as a clash check [30]. The SMC is the most common and widely used tool for BIM quality control in the GSA of the US, senate properties in Finland and bips in Denmark. The SMC was also used during the building design of the Korea Power Exchange headquarters as a tool for quality checks [31]. The SMC can perform various functions such as space, accessibility, structure, constructability, and regulation checks through a rule set that the user deﬁnes [10]. The Building and Construction Authority (BCA) of Singapore and the Ministry of Land, Infrastructure and Transport (MOLIT) of Korea are also developing a system that can check BIM-based building permission code [32,33]. BCA targets accessibility among building permission codes, and Korea has SEUMTER that checks building permission codes. In these projects, software that can automatically check each building permission code has been developed and applied.

2.4. Case Applications of Quality Control The projects presented in Table3 referred to the BIM guidelines and managed the BIM quality accordingly. The contents presented in this table show that the BIM guidelines referenced from the project are all diﬀerent, but common information such as space check, ﬂash check, etc. is required for quality control.

Table 3. Case studies for quality control.

Development Quality Control Project Name Overview/Purpose Content Organization Requirements

Checking space program Automation of BIM • • and level of security technologies about designs from the speciﬁed in the US GSA architect through guidelines for GSA, Georgia BIM-enabled design US courts BIM technology planning, design, Tech design guide automation design guide Development of egress construction, computing lab • [10] evaluation system and maintenance of according to the level court buildings of security

Promote the Space visualization • • possibility of plan for user Finland checking in Cost estimation BIM • music concert project pre-design stage Senate properties Energy calculation and requirements 2007 • [34] Use of BIM to reduce life cycle simulation • errors in the site Acoustic design •

Clash check with SMC as Case that applied • Denmark • an Industry foundation BIM technology in Rambøll 3D CAD classes (IFC) ﬁle the Rambøll Rambøll headquarters manual 2006 (AutoCAD Architecture, head oﬃce [35] Tekla, MagiCAD) [36]

Use of BIM in • USA architectural and Component clash check Wisconsin-13 BIM structural design Wisconsin (BIM) • Wisconsin State Space clash check pilot projects (some sectors guidelines • [37] of MEP) Appl. Sci. 2020, 10, 7074 6 of 25

Table 3. Cont.

Development Quality Control Project Name Overview/Purpose Content Organization Requirements

National Art • Veriﬁcation of IFC • Museum structure [36] International Automatic veriﬁcation competition held in Statsbygg General • Norway using EDM the Vestbanen, Guidelines for National Museum StatsbyggJotne model ServerLite Oslo, Norway. Building design competition EPM technology Space check (space Automatic model Information • [38] • arrangement and check) validation and Modeling v1.1 Energy analysis (heat loss quality control for • BIM model in step 1 calculated automatically)

Submit original BIM, IFC • 2X3 format, and design report about environmentally friendly Application of BIM Power Exchange Power Exchange • building (energy and quality headquarters performance) [36] headquarters assessment of Korea Power building Multidisciplinary building construction BIM design • Exchange construction assessment of the design design competition (functional quality, design competition quality based on BIM [28] energy eﬃciency) guidelines Visual checking, • functional quality checking, and analysis of energy eﬃciency

Check compliance • Code on Headroom height Singapore with building • accessibility in the Manoeuvring spaces iGrant permission code BCA • built environment The properties [32] related to • the accessibility 2013 of accessible

2.5. Summary The status of quality control using BIM was reviewed in terms of guidelines, software, and applications. In addition, there are methods for checking quality according to specific purposes such as building permission codes, safety, evacuation, cost, energy, etc. As mentioned in the Introduction, the current status is in a transitional phase in which plans of development and application are continuously evolving through the recognition of the importance of quality control. Limitations and additional requirements affect the overall status. However, some examples are directly or indirectly reflected in the quality control requirements to be developed in this research. Rule-based quality check software contains rules that make basic quality checks available; they can be extended by creating new rules for additional design requirements. Such rule-based quality checking software is being used in various applications for quality control. The SMC was utilized to validate and apply the criteria for quality checking developed in this paper. Most BIM guidelines refer to quality control but simply highlight its importance. Detailed components and the methodology for quality control are lacking. Therefore, a detailed plan that defines the application and scope of the requirements for quality control is needed. The development of guidelines that provide detailed requirements for quality checking is the purpose of this research. Common applicable elements and additional elements required for domestic regulation are derived. The applications of quality control analyzed in this paper were focused largely on physical checking (e.g., clash checking). Rule-based checking systems supporting quality control and quality checking in logical aspects have been planned and developed for more eﬀective quality control. Many applications verifying the requirements developed in this paper should be continuously conducted to establish Appl. Sci. 2020, 10, 7074 7 of 25 suitable quality control for the domestic practice environment. An application plan for automated quality control should be identiﬁed as a way of applying the requirements of quality control.

3. Design Quality in Design Processes Based on BIM In this study, the design process defined in domestic and international guidelines has been identified based on BIM. The traditional design process has been changed with the adoption of BIM. In traditional design processes, a substantial component should be handled in the construction document stage. However, in the BIM process, all participants (e.g., owner, architect, and contractor) collaborate on the work at all stages. If a main operator or special contractor has construction know-how, any design uncertainty and the construction period can be reduced, and construction quality can be improved [31]. Quality control targets should be established first in developing quality control requirements for improving the quality of architectural design. To this end, this research reviewed guidelines that include information about the application of BIM by the work process phase. The terms that define the process phases differ, but the basic concept is largely the same. Table4 presents quality control targets based on the IPD stage [39], through analysis of the design process. IPD is an integrated project delivery method that optimizes project efficiency through the collaboration of all participants at all phases of the construction industry [39]. Some parts of the construction stage are excluded because the information considered is centered on architectural design.

Table 4. Quality control targets by stage through analysis of the architectural design process.

Case Korea KIA (Architecture Design Finland Senate Properties USA CIC (BIM Project US AIA (IPD) [39,41] Quality Control Targets IPD Stage [39] Work Procedures) [40] (BIM Requirements) [42] Execution Planning Guide) [43]

Pre-survey Setting goals Cost Conceptualization • • • Programming Regulation, review of purpose Cost Space program • Pre-check regulation (expanded • • • Site analysis • programming) and size BIM environment Regulation information • • •

Space programming Architecture, structure, • Space model (spatial BIM) • check (spatial BIM) Spatial relationship • MEP, additional model • Building draft model Model check Functional analysis Pre-design of major • Energy analysis • • • (space-based) • Model clash check Criteria design (expanded (space programming) building system Structure analysis • schematic design) Clash check • Energy analysis Deliberation and building permit Regulation (ﬁre, • Lighting analysis • • • Cost estimation • Regulation check safety plan) • Mechanical analysis • Energy simulation • (deliberation and • Regulation check • building permit)

Complete building Checking final model • • components Building model (building by stage Prior review of basic design • • (including element BIM) Model crash check Regulation check • Detailed design (expanded • building system) Modeling by field Energy analysis design development) Writing basic drawing and • • • Clash check Regulation check specification by stage • • • Construction schedule Final energy simulation (deliberation and • Regulation analysis building permit) •

Writing • Implementation Re-examine basic design drawing construction document Regulation check • • documents Writing project drawing by ﬁeld Shop drawing (deliberation and • • (construction Deliberation and building permit (including building permit) documents) • regulation document)

4. Development of Design Quality Check Criteria Based on BIM To increase the reliability of design assessments and quality check results, the definition of the design phase work and criteria that reflect business requirements is necessary. The environment that can be applied to this system should then be established. Therefore, this section presents quality check criteria based on BIM through a review of the target of quality control, and the development of checklists for checking details (see Figure1). Architectural process based on BIM controls quality through BIM guidelines, building permission code, and rule-based S/W. These three quality controls can be classified into quality check requirements according to the level of application, scope, and level. Appl. Sci. 2020, 10, x 8 of 25

can be applied to this system should then be established. Therefore, this section presents quality check criteria based on BIM through a review of the target of quality control, and the development of checklists for checking details (see Figure 1). Architectural process based on BIM controls quality through BIM guidelines, building permission code, and rule-based S/W. These three quality controls Appl. Sci. 2020, 10, 7074 8 of 25 can be classified into quality check requirements according to the level of application, scope, and level.

FigureFigure 1. 1.Relevance Relevance ofof qualityquality control target target and and criteria. criteria.

4.1. Review4.1. Review of Quality of Quality Check Check Targets Targets Based Based on on BIM BIM ThisThis research research reviews reviews detailed detailed quality control control targets targets deduced deduced from BIM from guidelines BIM guidelines and the rule- and the based software for quality checks based on requirements of analysis for the BIM-based design rule-based software for quality checks based on requirements of analysis for the BIM-based design process. To reflect the domestic situation, targets of quality control that reflect Korean regulations are process. To reflect the domestic situation, targets of quality control that reflect Korean regulations are also deduced. Quality control targets are classified as physical information quality, logical also deduced.information Quality quality, control and data targets quality. are classified as physical information quality, logical information quality, andThe data applied quality. targets for quality checks are preferentially selected, applicable, and generalized Thequality applied check targetstargets, rather for quality than checks checks for are a specific preferentially item. However, selected, the applicable, current contents and generalizedare the qualitybasic check steps. targets, The targets rather should than be checks appropriate for a specific for the goals item. of However, a specific project, the current established contents in the are the basicfuture steps. through The targets the identification should be appropriateof additional chec for thek targets. goals In of the a specific case of logical project, information established and in the futurequality-based through the regulation identification checki ofng, additional quality check target targets. review In the work case ofshould logical be information progressed and quality-basedcontinuously. regulation Table 4 checking, excerpts from quality IPD, check Finland, target and review South workKorea, should although be the progressed methods continuously.vary for quality control targets. Quality control targets are excerpts from common or frequently used ones. Table4 excerpts from IPD, Finland, and South Korea, although the methods vary for quality control These targets are based on the classification as shown in Table 5. targets. Quality control targets are excerpts from common or frequently used ones. These targets are based on the classificationTable as shown 5. Quality in Tablecheck 5target. arrangements by classification.

Classification Targets Windows and doors fixed at the opening Required interval between objects Clash, structure, MEP elements Physical Cross-check between equal elements (architecture/architecture, structure/ structure, information quality service/service) Cross-check among other elements (architecture/architecture, structure/ structure, service/service) Connections between space and components Appl. Sci. 2020, 10, 7074 9 of 25

Table 5. Quality check target arrangements by classiﬁcation.

Classification Targets Windows and doors fixed at the opening Required interval between objects Clash, structure, MEP elements Cross-check between equal elements (architecture/architecture, Physical information quality structure/structure, service/service) Cross-check among other elements (architecture/architecture, structure/structure, service/service) Connections between space and componentsPosition of the components Headroom height Absence of space or object Incorrectly modelled component Evacuation facilities Building coverage ratio, floor area ratio Height restrictions Elevator installation Prevention of heat loss Logical information quality Regulation of space area Parking lot installation Exit route planning Structural standards Ceiling installation Manoeuvring spaces The required property, depending on the level of detail Space name, group name Type of space and each component Skin property (wall, slab, door, window) Height of space Whether spatial area matches with space program Data quality Whether each floor space area matches with total area Definition of spatial location Review all space groups (spatial groups), including the type Space number Obstruction checking of space consisting of external wall Door, window, slab area calculation Total area checking The properties of accessible

4.2. Development of Quality Check Criteria Based on BIM In this section, quality check criteria and checklists are developed through reconﬁguration of deduced quality check targets by requirement. As described above, quality check targets based on BIM can be classiﬁed into physical information quality, logical information quality, and data quality. For practical applications, they can be separated into space check criteria, design check criteria, and construction check criteria, depending on the applicable goals and methods. The deducted quality check targets and the relevance of criteria developed in this study are shown in Figure1. The targets of quality checking are spatial checking and design checking for improving design quality and construction checking. In addition, escape stairs installation criteria and heat loss prevention criteria are presented for regulation information checking in design check criteria.

4.2.1. Space Check Criteria Space check criteria are related to the checking of space components, space name, space area, and clash between spaces in the BIM according to the space programming required by the client. BIM that includes spatial information is referred to as spatial BIM. The spatial BIM is checked to determine whether the space programing is reﬂected appropriately. Appl. Sci. 2020, 10, 7074 10 of 25

4.2.2. Design Check Criteria Design check criteria are related to the checking of BIM data quality generated in the design process. These criteria have additional components including BIM validation and design guidelines. Further, they contain regulation information and related design. Detailed installation criteria for escape stairs and heat loss prevention are developed in this research. The regulations can be modiﬁed and supplemented depending on the intended use of the BIM.

4.2.3. ConstructionAppl. Sci. 20 Check20, 10, x Criteria 10 of 26 Appl. Sci. 2020, 10, x 10 of 26 Appl. Sci. 2020, 10, x 10 of 26 Appl. Sci. 20202020,, 1010,, xx 1010 of 2626 Construction4.2.3. Construction check criteria Check Criteria are related to the physical quality checking of BIM data for 4.2.3. Construction Check Criteria constructability4.2.3. checking. Construction Generally, Check Criteria such criteria refer to clash checking between the same kinds of 4.2.3.Construction Construction checkCheck criteriaCriteria are related to the physical quality checking of BIM data for building objectsConstruction and different check kinds criteria of building are related objects. to the physical quality checking of BIM data for constructabilityConstruction checking. check criteriaGenerally are, such related criteria to refer the physical to clash checking quality checkingbetween the of BIMsame datakinds for of constructabilityConstruction checking. check criteriaGenerally are, such related criteria to therefer physical to clash checking quality checking between the of BIMsame data kinds for of Table6 presentsbuildingconstructability objects some checking.and examples different Generally of kinds the quality,of such building criteria check objects. refer criteria to clash developed checking between in this study.the same kinds of constructabilitybuilding objects checking.and different Generally kinds ,of, suchsuch building criteriacriteria objects. referrefer toto clashclash checkingchecking betweenbetween thethe samesame kindskinds ofof buildingTable objects 6 presents and different some examples kinds of of building the quality objects. check criteria developed in this study. buildingTable objects 6 presents and different some examples kinds of of building the quality objects. check criteria developed in this study. Table 6 presents someTable examples 6. Quality of thethe check quality targets check and criteria cases. developed in this study. Table 6. Quality check targets and cases. Table 6. Quality check targets and cases. Classification Checking targetTable 6. Quality check Cases targets and cases. Description Classification Checking targetTable 6. Quality checkCases targets and cases.. Description Classification Checking target Cases Description Classification Checking target Cases  CheckingCheckingDescription of of space space area area within Classification Checking target Cases  • CheckingDescription of space area within  theCheckingwithin errorthe range of errorspace range area within  Checkingthe error range of space area within  ErrortheError error range range range can can be be changed changed SpaceSpace component component area area  • theErrorthe errorerror range rangerange can be changed Space component area  accordingErroraccording range to tocan the the becriteria criteria changed of of the andSpaceand quantity quantitycomponent check check area  Erroraccording range to can the be criteria changed of the Spaceand quantitycomponent check area accordingthe project to the criteria of the Spaceand quantitycomponent check area projectaccording to the criteria of the and quantity check accordingprojectEachfloor to space the criteria of the and quantity check  • Eachproject floor space area/quantity Space check  projectEacharea floor/quantity space checking area/quantity Space checkSpace criteria check  checkingEach floor space area/quantity Spacecriteria check  Eachchecking floor space area/quantity Spacecriteria check  Checkingchecking of space number and criteria  checkingCheckingchecking of space number and criteriacriteria   nameCheckingChecking according of of space space to numberspace number and • Checkingname according of space to numberspace and Space number and programnameand nameaccording according to space to Space number and nameprogram according to space Spacename number check and  Checkingprogramspace program of space number SpaceSpace numbername number andcheck name and  programChecking of space number namecheck check  uniqueCheckingChecking identifier of of space space in number the number BIM name check  • Checkingunique identifier of space in number the BIM datauniqueunique identifier identifier in in the the BIM uniquedata identifier in the BIM dataBIM data data  Definition of the specific types The absence of the  Definition of the specific types The absence of the  andDefinition required of theproperties specific for types componentThe absence type of in the the  DandDefinitionefinitionefinition required ofof of thetheproperties the specificspecific specific for typestypes componentThe absence type of inthe the and required properties for Thecomponent absence type of the in the • checkingand required properties for componentBIM datatype in the andcheckingtypes required and required properties for componentcomponentcomponentBIM type datatypetype in in thein thethe  (e.g.checking, object’s material) BIM data  checking(e.g.checkingproperties, object’s for material) checking BIM data  (e.g., object’s material) BIM data  (e.g.(e.g.(e.g.,,, object’s object’s material) material) • Building envelope/ Building envelope/  Definition of the building Design check BuildingThermal envelope/  Definition of the building Design check BuildingBuildingThermal envelope/  DDefinitionefinition of of the the building building Design check Thermal  • envelope/thermalDefinition of the building transmittance Design checkDesigncriteria check transmittanceThermal Denvelope/thermalenvelopeefinition /ofthermal the building transmittance Designcriteria check envelopetransmittanceThermal/Thermal propertyenvelope/thermal checking transmittance criteria propertytransmittance check envelope/thermalpropertyenvelope/thermaltransmittance checking transmittance transmittance criteriacriteria transmittancepropertytransmittancetransmittance property check property checking property check propertyproperty checking checking propertycheck check

 Checking of exit route walking  Checking of exit route walking Exit route check  distanceCCheckinghecking according of of exit exit route route to criterion walking Exit route check  • Cdistancehecking according of exit route to criterion walking ExitExit route route check check ofdistancewalking the exit according distanceroute accordingto criterion Exit route check distanceofto the criterion exit according route of the exitto criterion route of the exit route of the exit route

Clash check  CClashlash checking checking between between Construction ClashClash check check  • Clash checking between Construction (differentClash check kinds of  differentCdilashﬀerent checking kinds kinds ofbetween of building building checkConstruction criteria (di(differentﬀerentClash kinds check kinds of of  Cdifferentlashlash checkingchecking kinds ofbetweenbetween building checkConstruction criteria (differentobjects) kinds of objectsdifferentobjects (e.g. (e.g.,kinds, column column of building and slab) check criteria (different(differentobjects)objects) kindskinds ofof differentobjects (e.g. kinds, column of building and slab) checkcheck criteriacriteria objects) objectsand slab) (e.g., column and slab) objects) objects (e.g.,, columncolumn andand slab)slab)

Construction check criteria

Overlap check  OOverlapverlap checking checking between between the Overlap check  • Overlap checking between the Overlap(sameOverlap checkkinds check of  sameOtheverlap samekind checking kindof building of between building objects the (sameOverlap kinds check of  Osameverlap kind checking of building between objects the (same kinds(sameobjects) ofkinds objects) of (e.g.sameobjects, walls)kind (e.g., of building walls) objects (same(sameobjects) kindskinds ofof same(e.g.same, walls)kindkind ofof buildingbuilding objectsobjects objects) (e.g., walls) objects) (e.g.(e.g.,, walls)

4.3. Development of Quality Check Checklists 4.3. Development of Quality Check Checklists 4.3. Development of Quality Check Checklists 4.3. DevelopmentThis research of Qualitydeveloped Check specific Checklists checklists considering items and procedures according to the This research developed specific checklists considering items and procedures according to the qualityThis check research criteria developed developed specific in the checklists study. Theseconsidering checklists items can and prevent procedures missing according information, to the qualityThis check research criteria developed developed specific in the checklists study. Theseconsidering checklists items can and prevent procedures missing according information, to the quality check criteria developed in the study. These checklists can prevent missing information, Appl. Sci. 2020, 10, 7074 11 of 25

4.3. Development of Quality Check Checklists This research developed specific checklists considering items and procedures according to the quality check criteria developed in the study. These checklists can prevent missing information, making it possible to increase the accuracy of information about the required targets and contents. Through the use of these specific checklists, architects and designers are able to reflect design changes with continuous self-diagnostics. This is very important to improve quality checking results. Table7 presents an example of a checklist based on the design check criteria. This checklist contains commonly applicable content in the case of the Power Exchange headquarters competition [28] through analysis of processes and requirements. The heat loss prevention criteria that are the target of regulation checking are also included.

Table 7. Example of checklist for design check criteria.

Date/Time: Reviewer: Project name: Check content Checklist for design check criteria (suitability/incongruity/pending) Design quality basic (common) contents

The building element in the BIM, deﬁned using software when the initial creation (e.g., have to create using wall tool)

The type and attribute of all building elements in the BIM should be deﬁned

The property and type of the components must be deﬁned

The BIM should have level information

KPX headquarters competition contents

Stair plan should meet the conditions of regulations (e.g., installation of landing space and stair width/path)

Disability-related conditions should meet regulations (e.g., ramp slope, width)

Evacuation and ﬁre conditions should meet regulations (e.g., securing appropriate egress route from each space to safety zones)

Heat loss prevention criteria

The purpose of a building BIM should be deﬁned in the BIM as a property

Building elements exposed to ambient conditions (e.g., walls, slabs) should have property information about envelope

All building elements exposed to ambient conditions should have thermal transmittance as a property

Building elements exposed to ambient conditions should have thermal transmittance according to legal criteria

... Signature: Appl. Sci. 2020, 10, 7074 12 of 25

5. Application of Design Quality Checks Based on BIM

5.1. Suggested Quality Checking Process Appl. Sci.For 2020 application, 10, x to quality check-based BIM, quality check software that reﬂects quality12 check of 25 criteria and BIM data generated according to the BIM guidelines should be conﬁgured as shown in (3) The BIM data are checked according to the quality checking criteria using quality check software. Figure2. The quality check software can be applied to modify existing rules according to the criteria The architect and designer continually revise and review the design until the design developed for the quality check. Additionally, quality check software should enable users to develop requirements are properly reflected in the BIM data through the quality checking criteria. rules directly for automated quality checking according to altered criteria (e.g., revised regulations). (4) The quality checking results can be reported.

Figure 2. Process and element technology for the application of quality checking.

5.2. BIMThe Data suggested quality check process is as follows:

(1) AThe BIM architect created and according designer to produce BIM guidelines a design plan is needed with quality to conduct check criteriaquality usingchecking. BIM The software. BIM guidelineIn this can case, lead it isarchitects/designers necessary to define and the buildingevaluators object’s to create properties quality accordingmodels that to BIMcan be guidelines used to performfor thequality quality control check. and to increase the reliability of quality control results. These BIM guidelines (2)shouldThe include BIM created not only using basic the modeling BIM software methods is exported but also in additional the IFC format property [36]. definitions according to quality control criteria. The information input level for the BIM is LOD 2 [44] in the design (3) The BIM data are checked according to the quality checking criteria using quality check software. development phase. At this level, it is possible to define the details of the design check criteria and The architect and designer continually revise and review the design until the design requirements the construction check criteria among the quality check criteria. In this research, since the open BIM are properly reflected in the BIM data through the quality checking criteria. environment [27] is applied for effective sharing and exchange of design information, BIM data (4) The quality checking results can be reported. format adopts IFC 2x3 or higher standard format [36]. IFC are the main building SMART data model 5.2.standard BIM Dataand this format is registered by ISO as ISO 16739. IFC can be used to exchange and share BIM data between applications developed by different software vendors without the software having to supportA BIM numerous created according native formats. to BIM guidelinesAs an open is format, needed IFC toconduct do not belong quality to checking. a single Thesoftware BIM guidelinevendor therefore can lead they architects are neutral/designers and and independent evaluators of to a create particular quality vendor’s models thatplans can for be software used to performdevelopment quality [36]. control and to increase the reliability of quality control results. These BIM guidelines should include not only basic modeling methods but also additional property definitions according to quality5.3. Application control criteria.of Rule-Bas Theed information Quality Checking input levelSoftware for the BIM is LOD 2 [44] in the design development phase. At this level, it is possible to define the details of the design check criteria and the construction To achieve an effective quality check based on quality check criteria, quality evaluation using check criteria among the quality check criteria. In this research, since the open BIM environment [27] is quality checking software is very important. Depending on the purpose and nature of the quality applied for effective sharing and exchange of design information, BIM data format adopts IFC 2x3 or check criteria, some criteria can be checked using the rules provided by the existing software. higher standard format [36]. IFC are the main building SMART data model standard and this format is registered by ISO as ISO 16739. IFC can be used to exchange and share BIM data between applications 5.3.1. Quality Checking Using SMC (Modification and Addition of Rule Sets) developed by different software vendors without the software having to support numerous native The criteria developed in this study can be utilized with some modification of existing SMC rules according to quality check criteria. SMC provides various rules and types of rules set by a group depending on the type and purpose [4]. A new rule set can be created by combining various kinds of associated rules with the quality check criteria developed in this study. Each rule set can be configured in association with the criteria. Figure 3 shows the results of a quality check conducted by a recombinant rule set according to the space check criteria. Appl. Sci. 2020, 10, 7074 13 of 25 formats. As an open format, IFC do not belong to a single software vendor therefore they are neutral and independent of a particular vendor’s plans for software development [36].

5.3. Application of Rule-Based Quality Checking Software To achieve an eﬀective quality check based on quality check criteria, quality evaluation using quality checking software is very important. Depending on the purpose and nature of the quality check criteria, some criteria can be checked using the rules provided by the existing software.

5.3.1. Quality Checking Using SMC (Modification and Addition of Rule Sets) The criteria developed in this study can be utilized with some modification of existing SMC rules according to quality check criteria. SMC provides various rules and types of rules set by a group depending on the type and purpose [4]. A new rule set can be created by combining various kinds of associated rules with the quality check criteria developed in this study. Each rule set can be configured in association with the criteria. Figure3 shows the results of a quality check conducted by a recombinant rule set according to the space check criteria. Appl. Sci. 2020, 10, x 13 of 25

Figure 3. Example of quality check according to the space check criteria. Figure 3. Example of quality check according to the space check criteria.

5.3.2. Development5.3.2. Development of Rule-Based of Rule-Based Quality Quality Check Check Software (1) Structure quality checking criteria (1) Structure quality checking criteria The designThe design check check criteria criteria (focused (focused on on regulation regulation information) information) and and methods methods should should be defined be defined based on the relevant regulations for a rule-based quality checking system. The defined design based onchecking the relevant criteria should regulations be coded for for a regulation rule-based checking quality by checkinglinking the system.BIM data and The regulation defined design checkingcode. criteria Rule-based should regulation be coded forchecking regulation progresses checking through by linkingthe identification the BIM dataof the and targets regulation and code. Rule-basedcontents regulation of building checking objects in progresses BIM data compared through with the the identification regulation code. of the targets and contents of building objectsThe BIM in BIM property data information compared withcontains the the regulation names of code.materials that have further applicable Theinformation BIM property for various information disciplines. contains This property the names information of materials is utilized that to havedetermine further quality applicable checking results in the rule-based quality checking system. Software can be communicated using a information for various disciplines. This property information is utilized to determine quality checking neutral format throughout the open BIM environment, such as IFC, which is an international results instandard the rule-based [27,36,45]. quality Open BIM checking is a universal system. approach Software to canthe collaborative be communicated design, usingrealization, a neutral and format throughoutoperation the openof buildings BIM based environment, on open standards such as and IFC, workflows which is[27]. an IFC international provides the definitions standard for [27 ,36,45]. Open BIMadditional is a universal property approachinformation to through the collaborative the development design, of a property realization, set (PSET) and operation in the extension of buildings based onof openthe concept standards model andfor the workflows definition of [27 addition]. IFCal provides attributes theof the definitions BIM [16,36]. for buildingSMART additional property informationprovides through basic PSETs the development (e.g., Pset_WallCommon) of a property along set with (PSET) a methodology in the extension for defining of the additional concept model properties for building objects. The PSETs and properties for applying the regulations (e.g., heat loss for the definition of additional attributes of the BIM [16,36]. buildingSMART provides basic PSETs prevention criteria) are shown in Figure 4. Appl. Sci. 2020, 10, 7074 14 of 25

(e.g., Pset_WallCommon) along with a methodology for deﬁning additional properties for building objects. The PSETs and properties for applying the regulations (e.g., heat loss prevention criteria) are shown in Figure4. Appl. Sci. 2020, 10, x 14 of 25

Figure 4.FigureDeﬁnition 4. Definition of rules of rules for for applying applying regulations regulations (e.g., (e.g., heat heat loss loss prevention prevention criteria). criteria).

(2) Development(2) Development of rules of rules through through the the SMC SMC API API environment environment As describedAs described above, SMCabove, can SMC be can utilized be utilized for all for of theall developedof the developed quality quality check check criteria. criteria. Therefore, this studyTherefore, uses SMC this asstudy the uses software SMC as for the rule-based software for quality rule-based checking. quality checking. Regulation information should be structuralized in conjunction with IFC for using rules that are Regulation information should be structuralized in conjunction with IFC for using rules that are related to regulations in the SMC [36,46]. The rules have to be defined as a separate class (Java file) related toin regulations the SMC Java in API the environment SMC [36,46 (See]. The Figure rules 5), have and the to berequired defined properties as a separate and checking class (Javaorder file) in the SMCmust Java be API defined environment with IFC (Seestructure Figure and5), regulation and the requiredcontents [36]. properties This study and focuses checking on orderheat loss must be defined withprevention IFC structureregulation andchecking regulation criteria and contents generate [36s the]. Thiscoded study Java file focuses from delimited on heat rules loss (e.g., prevention a regulationcheck checking of building criteria district, and build generatesing uses, building the coded envelope Java fileproperty, from and delimited thermal transmittance). rules (e.g., a check of building district,The thermal building transmittance uses, building (U-value) envelope is obtained property, by and thermal transmittance). Appl. Sci. 2020, 10, x 15 of 25 1 𝑈𝑡ℎ𝑒𝑟𝑚𝑎𝑙 𝑡𝑟𝑎𝑛𝑠𝑚𝑖𝑡𝑡𝑎𝑛𝑐𝑒, 𝑈𝑣𝑎𝑙𝑢𝑒 𝑊⁄㎡𝐾= (1) ∑𝑡ℎ𝑒𝑟𝑚𝑎𝑙 𝑟𝑒𝑠𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡ℎ𝑖𝑐𝑘𝑛𝑒𝑠𝑠 𝑡ℎ𝑒𝑟𝑚𝑎𝑙 𝑟𝑒𝑠𝑖𝑠𝑡𝑎𝑛𝑐𝑒㎡ 𝐾𝑊= (2) 𝑡ℎ𝑒𝑟𝑚𝑎𝑙 𝑐𝑜𝑛𝑑𝑢𝑐𝑡𝑖𝑣𝑖𝑡𝑦𝑘𝑐𝑎𝑙㎡ ℎ℃

FigureFigure 5. Eclipse 5. Eclipse Interface Interface deﬁning defining rules rules for bu buildingilding envelope envelope property property definition. deﬁnition.

A new rule set that corresponds to the heat loss prevention criteria is generated with one of the rules (Java file) developed in the Rule Set Manager of SMC. The heat loss is obtained by 𝑄=𝑈×𝐴 ×∆𝑇 (3) A: Surface area ∆T: Temperature difference (T1, T2) Regulation checking is then conducted in conjunction with the BIM data. It is necessary to continuously modify errors that occur through regulation checking; a final design can be derived after regulation checking is completed. In particular, final design checking criteria can be utilized by legality checking for building permission [4]. Figure 6 shows the rule-based quality checking result according to design check criteria.

Figure 6. Example of rule-based quality checking results according to design check criteria (e.g., criterion, heat loss prevention; rule, thermal transmittance checking). Appl. Sci. 2020, 10, x 15 of 25

Appl. Sci. 2020, 10, 7074 15 of 25

The thermal transmittance (U-value) is obtained by

1 U(thermal transmittance, U value) W/m2K = P (1) − thermal resistance

2 thickness thermal resistance m K/W = (2) Figure 5. Eclipse Interface defining rulesthermal for building conductivity envelopekcal property/m2h definition.◦ C

A new rule set that corresponds to the heat loss prevention criteria is generated with one of the rules (Java file) file) developed in the Rule Set Manager of SMC. The heat loss is obtained by Q = U A ∆T (3) 𝑄=𝑈×× 𝐴 ××∆𝑇 (3) A: Surface area A: Surface area ∆T: Temperature difference (T1, T2) ∆T: Temperature difference (T1, T2) Regulation checking is then conducted in conjunctionconjunction with the BIM data.data. It It is is necessary to continuously modifymodify errorserrors that that occur occur through through regulation regulation checking; checking; a final a final design design can becan derived be derived after afterregulation regulation checking checking is completed. is completed. In particular, In particular, final design final design checking checking criteria criteria can be utilizedcan be utilized by legality by legalitychecking checking for building for building permission permission [4]. Figure [4].6 showsFigure the 6 shows rule-based the rule-based quality checking quality result checking according result accordingto design checkto design criteria. check criteria.

Figure 6.6. ExampleExample of of rule-based rule-based quality quality checking checking results result accordings according to design to design check criteria check (e.g.,criteria criterion, (e.g., criterion,heat loss prevention;heat loss prevention; rule, thermal rule transmittance, thermal transmittance checking). checking).

(3) Development of rule-based quality check software The development through the API environment of a specific program may cause problems such as limitations and dependencies of the API module. Therefore, in this research, we developed software that can develop the self-developed function and check it. This software provides the text of select code articles from the Korean Building Act, its enforcement decrees, and the regulations associated with them. The rule is defined and managed with building code checklists based on those currently used in actual architectural firms. The rules are based on the quality checking criteria, and the system library functions and the scripts are generated by the rules. In the case of a check of elevator installation criteria, the number of elevator installation is obtained by Total o f living space over 6 f loors 3000 m2 = 2 (4) ≤ Appl. Sci. 2020, 10, x 16 of 25

(3) Development of rule-based quality check software The development through the API environment of a specific program may cause problems such as limitations and dependencies of the API module. Therefore, in this research, we developed software that can develop the self-developed function and check it. This software provides the text of select code articles from the Korean Building Act, its enforcement decrees, and the regulations associated with them. The rule is defined and managed with building code checklists based on those currently used in actual architectural firms. The rules are based on the quality checking criteria, and the system library functions and the scripts are generated by the rules. In the case of a check of elevator installation criteria, the number of elevator installation is obtained by

𝑇𝑜𝑡𝑎𝑙 𝑜𝑓 𝑙𝑖𝑣𝑖𝑛𝑔 𝑓𝑠𝑝𝑎𝑐𝑒 𝑜𝑣𝑒𝑟6 𝑙𝑜𝑜𝑟𝑠 3000 ㎡ =2 (4) Appl. Sci. 2020, 10, 7074 16 of 25 𝑇𝑜𝑡𝑎𝑙 𝑜𝑓 𝑙𝑖𝑣𝑖𝑛𝑔 𝑓𝑠𝑝𝑎𝑐𝑒 𝑜𝑣𝑒𝑟6 𝑙𝑜𝑜𝑟𝑠 3000㎡ (5) 2 Total𝑡𝑜𝑡𝑎𝑙 o f living 𝑜𝑓 space 𝑙𝑖𝑣𝑖𝑛𝑔 over 𝑠𝑝𝑎𝑐𝑒6𝑓𝑙𝑜𝑜𝑟𝑠6 f loors > 3000 3000 ㎡ m (5) 2 (6) total o f living space 6 f loors 3000 m2 2000 ㎡ − + 2 (6) 2000 m2 𝑚𝑎𝑥𝑖𝑚𝑢𝑚 𝑓𝑙𝑜𝑜𝑟 𝑎𝑟𝑒𝑎 𝑜𝑓 𝑒𝑎𝑐ℎ𝑓𝑙𝑜𝑜𝑟 𝑒𝑥𝑐𝑒𝑒𝑑𝑖𝑛𝑔 31m1500 ㎡2 maximum f loor area o f each f loor exceeding 31 m 1500 m 1 − + 1(7) (7) 30003000 m㎡2 Figure7 is an example of a ﬂowchart for analyzing the regulation before the development of rules Figure 7 is an example of a flowchart for analyzing the regulation before the development of and software. rules and software.

FigureFigure 7. 7.Flowchart Flowchart for for checkingchecking installation installation of ofelevator. elevator.

FigureFigure8 shows 8 shows the processthe process of applyingof applying a a rule rule to to check check thethe installation installation of of the the ceiling. ceiling. Appl. Sci. 2020, 10, x 17 of 25

Figure 8. Example of scripting using rule (e.g., installation of ceiling). Figure 8. Example of scripting using rule (e.g., installation of ceiling). Figure 9 shows the result of the quality checking as exemplified in the installation of the ceiling and the functions of software.

Figure 9. Example of rule-based quality checking results according to design check criteria (e.g., installation of ceiling).

6. Usage and Verification of Proposed Quality Checking Requirements

6.1. Overview In this section, a quality check of BIM data was performed to validate the applicability of the developed quality check criteria, by using rule-based quality check software. Some of the criteria for space and construction checks were established based on modifications to the basic rules supported by SMC, as previously mentioned. For the design check criteria, heat loss prevention criteria were additionally developed, and these also were adopted in quality checks. Revit and ArchiCAD were used as the BIM software. The properties of regulation information in the design criteria were input Appl. Sci. 2020, 10, x 17 of 25

Appl. Sci. 2020, 10, 7074 17 of 25 Figure 8. Example of scripting using rule (e.g., installation of ceiling).

FigureFigure9 9shows shows the the result result of of the the quality quality checking checking as as exempliﬁed exemplified in in the the installation installation of of the the ceiling ceiling andand the the functions functions of of software. software.

FigureFigure 9.9. ExampleExample of rule-based quality quality checking checking result resultss according according to design to design check check criteria criteria (e.g., (e.g.,installation installation of ceiling). of ceiling).

6.6. UsageUsage andand VeriﬁcationVerification of of Proposed Proposed Quality Quality Checking Checking Requirements Requirements

6.1.6.1. OverviewOverview InIn this this section, section, a a quality quality check check of of BIM BIM data data was was performed performed to to validate validate the the applicability applicability ofof the the developeddeveloped quality quality check check criteria, criteria, by by using using rule-based rule-based quality quality check check software. software. Some Some of of the the criteria criteria for for spacespace and and construction construction checks checks were were established established based based on on modiﬁcations modifications to to the the basic basic rules rules supported supported byby SMC, SMC, as as previously previously mentioned. mentioned. ForFor thethe designdesign checkcheck criteria,criteria, heatheat lossloss preventionprevention criteriacriteriawere were additionallyadditionally developed,developed, andand thesethese alsoalso werewere adopted adopted in in quality quality checks. checks. RevitRevitand and ArchiCAD ArchiCADwere were usedused as as the the BIM BIM software. software. TheThe propertiesproperties ofof regulation regulation information information inin the the design design criteria criteria were were input input with basic modeling according to the LOD of BIM, as suggested in this study. A summary of the application example models is provided in Table8.

6.2. Results of the Applied Criteria The developed quality check criteria, which consist of a space check, design check and construction check were applied. Continuous quality checking and revision allowed the improvement of the ﬁnal design plan. This may provide a basis for improving accuracy and eﬃciency in aspects of project management.

6.2.1. Space Check Criteria Space check criteria are the criteria for evaluating whether BIM data reflects the space program. In this study, the basic rule set in SMC was modified to develop targeted model-specific rules for the space program. A quality check on this rule was performed. Table9 shows the results from the quality check for each case model. Appl.Appl. Sci. Sci. 20 202020, 10, 10, x, x 1818 of of 26 26 Appl. Sci. 20202020,, 1010,, xx 1818 of 2626 withwith basic basic modeling modeling according according to to the the LOD LOD of of BIM, BIM, as as suggested suggested in in this this study. study. A A summary summary of of the the with basic modeling according to the LOD of BIM, as suggested in this study. A summary of thethe Appl. Sci. 2020applicationapplication, 10, 7074 example example models models is is provided provided in in Table Table 8. 8. 18 of 25 application example models is provided in Table 8. TabTablele 8. 8.Overview Overview of of case case models models. . Table 8. Overview of case models. Table 8. OverviewTable 8. ofOverview case models. of case models. Image Description ImageImage DescriptionDescription ImageImage DescriptionDescription

  LLocation:ocation:Location: Seoul Seoul (Site(Site (Site zone: zone: zone: central) central) central) • Location: Seoul (Site zone: central)  Purpose:Location: business Seoul (Site and neighborhoodzone: central) • Purpose:Purpose: business business and and neighborhood neighborhood living living facilities facilities CaseCase 1 1  Purpose:living facilities business and neighborhood living facilities Case 1   NumberNumber of of floors: floors: 6 6basement basement floors, floors, 15 15 ground ground floors floors Case 1  Number ofof floors: floors: 6 basement6 basement floors, floors, 15 15 ground floors  Number of floors: 6 basement2 2 floors, 15 ground floors •  AreaArea of of land: land: 694.4 694.4 m m 2  Areaground of floors land: 694.4 m 2 Area of land: 694.4 m2 •

  LLocation:ocation:Location: Gyeonggi-doGyeonggi Gyeonggi-do-do (Site (Site (Site zone: zone: zone: central) central) central) • Location: Gyeonggi--do (Site zone: central)   Purpose:Purpose:Purpose: cultural cultural and and and business business business facilities facilities facilities CaseCase 2 2 • Purpose: cultural and business facilities CaseCase 2 2   NumberNumberNumber of of floors:floors: floors: 3 3 basement 3basement basement floors, floors, floors, 15 15 15 ground ground floors floors • Number of floors: 3 basement floors, 15 ground floors   AreagroundArea of of floorsland: land: 10,802 10,802 m2 m2  Area of land: 10,802 2m2  Area ofof land: land: 10,802 10,802 m m2 •

  Location:Location: Gyeonggi-do Gyeonggi-do (Site (Site zone: zone: central) central) • LLocation:ocation: Gyeonggi Gyeonggi--dodo (Site (Site zone: zone: central) central)  Purpose:Location: cultural Gyeonggi and- businessdo (Site facilitieszone: central) •  Purpose:Purpose: cultural cultural and and business business facilities facilities CaseCase 3 3  Purpose:Number of cultural floors: 2 and basement business floors, facilities 13 CaseCase 3 3 •  NumberNumber of of floors: floors: 2 2basement basement floors, floors, 13 13 ground ground floors floors Case 3  Numberground floors of floors: 2 basement floors, 13 ground floors  Number of floors: 2 basement2 2 floors, 13 ground floors   AreaArea of of land: land: 10,802 10,802 m2 m2  Area ofof land: land: 10,802 10,802 m m 2 •

  Location:Location: Gyeonggi-do Gyeonggi-do (Site (Site zone: zone: central) central) • LLocation:ocation: Gyeonggi Gyeonggi--dodo (Site (Site zone: zone: central) central)  Purpose:Location: cultural Gyeonggi and- businessdo (Site facilitieszone: central) • Purpose:Purpose: cultural cultural and and business business facilities facilities CaseCaseCase 4 4 4  Purpose:Number of cultural floors: 4 and basement business floors, facilities 11 Case 4 •  NumberNumber of of floors: floors: 4 4basement basement floors, floors, 11 11 ground ground floors floors  Numberground floors of floors: 4 basement floors, 11 ground floors   Area of land: 10,8022 m2 2  AreaArea of land: 10,80210,802 m m 2 • Area of land: 10,802 m 2

6.2.6.2. Results Results of of the the Applied Applied Criteria Criteria 6.2. Results of the Applied Criteria TableTheThe developed9. developedThe result qualityof quality quality check checking check criteria, criteria, against which space which check consist consist criteria of of in a acase space space models. check, check, design design check check and and The developed quality check criteria, which consist of a space check, design check and constructionconstruction check check were were applied. applied. Continuous Continuous quality quality checking checking and and revision revision allowed allowed the the construction check were applied. Continuous quality checkingError and revision allowed the constructionimprovementSpace Check checkof the Criteria final were Checklistdesign applied. plan. This Continuous may prov qualityide a basis checking for improving and revisionaccuracy and allowed efficiency the improvementimprovement of of the the final final design design plan. plan. This This may may prov provideide a a basis basis for for improving improving accuracy accuracy and and efficiency efficiency improvementin aspects of project of the final management. design plan. This mayCase prov 1ide Casea basis 2 for Caseimproving 3 Case accuracy 4 and efficiency inin aspects aspects of of project project management. management. Spacein aspects objects, of which project are locatedmanagement. in all planned 0 0 0 0 space,6.2.1. should Space be Check defined. Criteria 6.2.1.6.2.1. Space Space Check Check Criteria Criteria Space6.2.1. objects Space should Check be Criteria defined using Space check criteria are the criteria for evaluating whether BIM data reflects the space program. non-duplicatedSpaceSpace check check space criteria criteria number are are (facility the the criteria criteria number) for for evaluating evaluating whether whether BIM BIM data data reflects reflects the the space space program. program. In thisSpace study, check the criteria basic rule are setthe in criteria SMC wasfor evaluatingmodified0 to whether develop 0 BIM targeted 0data reflectsmodel 0 - specificthe space rules program. for the asInIn the this this attribute, study, study, accordingthe the basic basic torule rule the set set list in in SMC theSMC space was was m modifiedodified to to develop develop targeted targeted model model--specificspecific rules rules for for the the program.Inspace this program.study, the A basic quality rule check set in on SMC this was rule m wasodified performed. to develop Table targeted 9 shows model the results-specific from rules the forqualit they spacespace program. program. A A quality quality check check on on this this rule rule was was performed. performed. Table Table 9 9 shows shows the the results results from from the the qualit qualityy spacecheck program. for each caseA quality model. check on this rule was performed. Table 9 shows the results from the quality Spacecheckcheck objects for for each each should case case be model. model. defined using non-duplicatedcheck for each space case name model. as the attribute, 0 0 0 0 according to theTable listTable in 9. the 9.The The space result result program. of of quality quality checking checking against against space space check check criteria criteria in i ncase case models models. . Table 9. The result of quality checking against space check criteria in case models. The BIM should considerTable 9. The space result objects, of quality which checking against space check criteria in case models. 22 1 19 0 ErrorError are defined in the space program. Error SpaceSpace check check Criteria Criteria Checklist Checklist CaseCase CaseCase CaseCase CaseCase Space objects should beSpace categorized check intoCriteria zones Checklist Case Case Case Case Space check Criteria Checklist21 29 34Case Case 21 Case Case according to the purpose of the space. 1 1 2 2 3 3 4 4 1 2 3 4 SpaceSpace objects, objects, which which are are located located in in all all planned planned space, space, should should be be TheSpace total area objects, of floor which space are objects located on eachin all floor planned space, should be 0 0 0 0 0 0 0 0 Spacedefined. objects, which are located in all planned space, should be 0 0 0 0 ofdefined. thedefined. building should be within the error range 0 23 220 0 0 0 0 specifieddefined. in the spatial plan for the planning area Appl. Sci. 2020, 10, 7074 19 of 25

Table 9. Cont.

Error Space Check Criteria Checklist Case 1 Case 2 Case 3 Case 4 The quantity of floor space objects on each floor of the building should be in accordance with the 10 72 5 3 number of objects specified in the spatial plan The area of spatial objects should be within the error range specified in the spatial plan for the 24 2 59 0 planning area. The quantity of spatial objects should be in accordance with the number of objects specified 73 4 2 0 in the spatial plan. Spatial objects with minimum height conditions defined in the spatial plan must meet the 5 8 6 5 corresponding condition. Space objects should not interfere with 135 287 202 19 each other.

Problems identiﬁed in the quality check based on space check criteria are described in Table 10. In addition, solutions to these problems are suggested.

Table 10. Results of quality checking based on space check criteria.

Section Problems and Solutions

The error was caused by typing error or misidentiﬁcation of user • The error was caused by mis-recording of the space name and number, • which is based on the space program when creating BIM User input error The error occurred due to modiﬁcations to the space program • already applied Therefore, the user needs to pay special attention at every step of • entering and modifying information

The error occurred when the program Error in planning • space program automatically changed part of a space name (Excel-based program) (e.g., cafe to café) System error The error in space area was due to diﬀering • Error in quality check criteria for modeling space in each country on SMC (domestic, based on center line; SMC, based on inside dimensions)

In the case of “interference check of the space object” (a rule in SMC), • clash detection is checked between space and building objects, but not Error of quality between space objects. This causes a lot of error. check criteria Clash detection between space and building objects should be added to • the checklist to remind users to consider this when creating a BIM. Appl. Sci. 2020, 10, 7074 20 of 25

6.2.2. Design Check Criteria The design check criteria evaluate whether BIM data reﬂect the design guidelines. BIM validation in SMC was utilized. In addition, a quality check on heat loss prevention criteria was conducted. As a result of the quality check on design check criteria, the problems shown in Table 11 were identiﬁed.

Table 11. The results of quality checks against the design check criteria in case models.

Error Design Check Criteria Checklist Case 1 Case 2 Case 3 Case 4 The building element in BIM should be defined using software during the initial creation (e.g., a wall should 0 0 0 0 be created using the wall tool). The building elements used in the creation of the BIM 0 0 0 0 should be constructed. The type and attributes of all building elements in the 0 0 0 0 BIM should be defined. The BIM should have level information. 0 0 0 0 The location information should be defined in the BIM 0 1 0 1 as a value of the property. The purpose of a building BIM should be defined in the 0 1 1 0 BIM as a value of the property. Building elements exposed to ambient conditions (e.g., wall, slab) should have property information about 0 0 0 0 the envelope. All building elements exposed to ambient conditions should have thermal transmittance as a value of 15 20 26 24 the property. Building elements exposed to ambient conditions should 15 16 23 6 have thermal transmittance according to legal criteria.

As a result of the quality check against design check criteria, the problems shown in Table 12 were identiﬁed. Solutions to these problems are also suggested in the table.

Table 12. The results of quality checks against design check criteria.

Section Problems and Solutions

This error occurs if the property information to be input (such as • regulation information) in addition to basic property information is omitted or improperly entered. User input error The information to be entered is different depending on the target of • the quality check. Therefore, the user must first define the scope and target of quality checks to reduce error.

Even if the BIM was created properly, • the exported IFC ﬁle could have an Error of BIM software error [36]. To minimize errors, users should identify (IFC export/import) [36] • System error problems according to the software and object.

Error of quality check - in SMC

In the initial stages, current regulation criteria are not suﬃcient, • Error in quality unlike the criteria for the basic quality check. Therefore, it is necessary check criteria to develop the various rules for regulation checking. Appl. Sci. 2020, 10, 7074 21 of 25

6.2.3. Construction Check Criteria The construction check criteria are related to a physical evaluation of the degree to which construction criteria are reﬂected. The quality check was conducted after modifying the basic rule set in SMC to derive the rules for the construction check. As a result of the quality check against construction check criteria, the problems shown in Table 13 were identiﬁed.

Table 13. The results of quality checks against the construction check criteria in case models.

Error Construction Check Criteria Checklist Case 1 Case 2 Case 3 Case 4 There should be no clash or interference between the 753 20 42 16 building elements in the BIM. There should be no interference between the same 395 23 2 11 building elements in the BIM. There is no duplicated preparation of building elements 17 13 8 20 in the BIM. The upper and lower elements of the building should be 111 26 30 7 drawn as encountered.

During the quality check against construction check criteria, the problems shown in Table 14 were encountered, and the solutions to these problems are suggested in the table.

Table 14. The results of quality checks against construction check criteria.

Section Problems and Solutions

Most errors occurred while creating the BIM using the software. • These problems could be solved by creating a BIM according to the User input error • BIM guidelines.

Even if the BIM was created properly, • the exported IFC ﬁle could have errors [36]. Errors in BIM software To minimize errors, the user should identify • (IFC export/import) [36] problems according to the software and object. System error

Some rules provided by SMC were • Errors in quality checks inconsistent with the domestic situation. in SMC These rules should be excluded when checking the model.

It is necessary to adjust criteria to the domestic situation by Error in quality • check criteria coordinating the basic rules in SMC.

6.3. Analysis of the Results and Achievement As described above, the veriﬁcation process of the proposed quality checking requirements was conducted. According to the characteristics of the case model, the achievement of the quality check result by the quality check target was diﬀerent. The achievement of the quality checking is obtained by Appl. Sci. 2020, 10, 7074 22 of 25

= Average value Achievement (Re f lectivity Expected average value/100) × Relectivity (8) 100 × Total re f lectivity × In detail, the achievement of the quality check target for Case 1 is shown in the following Tables 15 and 16.

Table 15. The achievement score by criteria. Appl. Sci. 2020, 10, x 22 of 25 Criteria Space Check Design Check Construction Check Reﬂectivitytarget (%) Data quality 30 Logical information 30 Logical information 40 Physicalquality information quality quality Physical information quality Physical information quality Quality Check target Logical information quality Data quality Data quality Logical information quality Average value 26 Data 3 quality 319 ExpectedAverage average value 26 3 319 50 50 80 Expectedvalue average value 50 50 80

Table 16. The achievement score by quality check target.

QualityQuality Check Check Target Target Space Space Check Check Design Design Check Check Construction Construction Check Check Total Total PhysicalPhysical information information quality quality 10 10 2 2 319 319 331 331 Logical information quality 0 2 80 82 Logical informationData quality quality 42 0 2 2 0 80 43 82 Data quality 42 2 0 43

According to the quality checking requirements proposed in this study, the comparison of achievement according to the quality checking result resultss of each case model is shown in the following Figure 1010.. It is possible to secure design quality through continuous quality control by reflecting reﬂecting the result of quality checking.

Figure 10. The comparison of achievement according to the quality checking results. Figure 10. The comparison of achievement according to the quality checking results.

7. Conclusions A vast amount of design information exists throughoutthroughout the construction industry, and design assessment and quality control should be conducted to deal with this information. Continuous checks in the design phase should be made; a a BIM-based qu qualityality check check is is an an effective eﬀective way way to to achieve achieve this. this. However, BIM-based quality checking cannot be achieved systematically due to lack of criteria and an application plan (e.g., system side), although the approach can reorganize and assess design information. This study aimed to developed element technology and application plans for systematic quality control, and to improve the quality of architectural design in the BIM environment. Specifically, the research analyzed output information and design phase work in the design process, and then derived detailed quality control targets for a series of cases (e.g., guidelines, software) and Korean regulations. The targets for quality control were developed with respect to requirements for space check criteria, design check criteria, and construction check criteria according to the nature and purpose of the works. The regulation check contents of these requirements were included in the design check Appl. Sci. 2020, 10, 7074 23 of 25

However, BIM-based quality checking cannot be achieved systematically due to lack of criteria and an application plan (e.g., system side), although the approach can reorganize and assess design information. This study aimed to developed element technology and application plans for systematic quality control, and to improve the quality of architectural design in the BIM environment. Specifically, the research analyzed output information and design phase work in the design process, and then derived detailed quality control targets for a series of cases (e.g., guidelines, software) and Korean regulations. The targets for quality control were developed with respect to requirements for space check criteria, design check criteria, and construction check criteria according to the nature and purpose of the works. The regulation check contents of these requirements were included in the design check criteria. In addition, definitions of the process and development of various required element technologies were suggested for applications in architectural design quality control based on BIM. The results of these quality control processes were verified by quality checking software (including the developed contents) based on rules. The quality control requirements classified targets to be considered when creating and assessing BIM data, and are essential for supporting common works in the design process. Therefore, design quality could be improved when quality control requirements are actively utilized. In addition, checklists classified by detailed criteria for design requirements can be utilized to track the progress of quality checking through self-checking. Architects and designers who wish to check design quality in the design process or evaluation can expect improvements in quality by following a step-by-step approach with respect to the detailed checking of results. Rule-based quality checking software can support quality checking according to quality control requirements, and reduce inefficiencies in the use of time and human resources. Errors noted in quality checking results could be minimized by improving the performance of the checking system with respect to the requirements. It is expected that software would maximize the reliability of results and the efficiency of quality control. The scope of the quality control requirements applied in this study is limited to the design process, and it may be impractical to apply quality control throughout the project’s life cycle. To overcome this limitation, the application scope of quality control should be expanded to various phases such as construction and maintenance.

Author Contributions: Conceptualization, J.C. and I.K.; data curation, J.C., S.L. and I.K.; formal analysis, J.C. and S.L.; funding acquisition, I.K.; investigation, J.C. and I.K.; methodology, J.C.; project administration, I.K.; resources, J.C., S.L.; supervision, I.K.; validation, J.C., S.L. and I.K.; visualization, S.L.; writing—original draft, J.C. and S.L.; writing—review & editing, J.C. and I.K. All authors have read and agreed to the published version of the manuscript. Funding: This research was supported by a grant (20AUDP-B127891-04) from the Architecture & Urban Development Research Program funded by the Ministry of Land, Infrastructure and Transport of the Korean government. Conﬂicts of Interest: The authors declare no conﬂict of interest.

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