• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.3-13
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• 2010

The purpose of this research is to develop a conceptual model that establishes a new approach for functional area cost estimating in the schematic design phase. A cost estimating model should consider not only the estimate accuracy, but also the flexibility to the design alternatives and user-oriented serviceability. Therefore, this research uses the method that classifies various facilities of a building according to its functions by analyzing historical data. After setting the functional area as cost parameter, a formula which can estimate functional area cost is derived from statistical analysis. Finally, to validate the proposed conceptual model, it is applied to historical data of a military barrack project. It enables customized space planning reflecting client's needs and compares the cost of various design alternatives as well as improves estimate accuracy.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.661-670
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• 2016

In 2000, post-construction evaluation was introduced for the purposes to evaluate demand, cost, and construction period of public construction projects and to reduce errors of public order agencies. However, pricing guide of post-construction evaluation has not been established, which becomes a cause of quality degradation of post-construction service and conflict occurrence. This study suggests the pricing guide in the form of percentage of construction cost method and cost plus fee method based on data of post-construction evaluation. This study investigates the construction costs and service costs for post-construction evaluation and conducts the comparative analysis of 'percentage of construction cost method' and 'cost plus fee method.' The analysis result shows 'cost plus fee method' is more accuracy than 'percentage of construction cost method.' In particular, cost plus fee method includes various correction coefficients, such as distance, area, and integration, in order to reflect the project characteristics of each infrastructure, and suggests linear construction (roads, railways), nonlinear construction I (housing and industry complex), and nonlinear construction II (airports, seaports, dams, water and sewage).

• Journal of the Korea Institute of Building Construction
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• v.10 no.2
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• pp.75-80
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• 2010

With the intensifying of price competition and structural diversifications, the uncertainty of the domestic housing market has been increased. This highlights the importance of the planning stage of construction projects, and the increased need for a higher level of accuracy in approximate estimates. Currently, a number of research and development programs to calculate construction cost at the initial planning stage are being conducted. However, there are few cases in which local characteristics are considered in deriving the results. If local calibration can be conducted during estimates, more accurate cost estimates will be enabled. This could also play a major role in ensuring the success of a project. Therefore, the purpose of this research is to develop a calculation methodology and a model for a local index based on the historical data of public apartment buildings, and to derive a local index that supports accurate construction cost estimates.

• Korean Journal of Construction Engineering and Management
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• v.8 no.4
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• pp.110-118
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• 2007

For deciding the owner's budget of the building construction in the predesign stage, the probabilistic methodologies for estimating the cost are often studied, however these parameter-based conceptual estimating methodology has limitation of applying it to the practical business because it hardly can link the design decision-making and the cost estimating and control. Besides if the result of detail estimating after detail design is over the budget, locally and arbitrarily control the level of interior design and fix the design. This research proposed the prototype-based cost estimating model for building interior construction which leads to estimate the interior cost easily linking with design decision-making and supports to evaluate the design alternatives in the schematic design and the design development stage for office buildings. The model divides the building on the design process by Element Breakdown Structure and presents the design alternative by selecting the elements of each room from the database accumulated the historical office buildings' prototypes and estimates the cost. The 2 case studies presented to validate the effectiveness of as the linking tool integrating the design and construction data and applicability to the practical design on the presented prototype-based model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1693-1705
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• 2013

To restore old aqueduct in Korea which is a irrigation bridge to supply water in paddy field area, it is needed to estimate approximate costs of restoration because the basic design for estimation of construction costs is often ruled out in current system. In this paper, estimating models of construction costs were developed on the basis of performance data for restoration of RC aqueduct bridges since 2003. The regression analysis (RA) model and case-based reasoning (CBR) model for the estimation of construction costs were developed respectively. Error rate of simple RA model was lower than that of multiple RA model. CBR model using genetic algorithm (GA) has been applied in the estimation of construction costs. In the model three factors like attribute weight, attribute deviation and rank of case similarity were optimized. Especially, error rate of estimated construction costs decreased since limit ranges of the attribute weights were applied. The results showed that error rates between RA model and CBR models were inconsiderable statistically. It is expected that the proposed estimating method of approximate costs of aqueduct restoration will be utilized to support quick decision making in phased rehabilitation project.

• Korean Journal of Construction Engineering and Management
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• v.17 no.2
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• pp.31-38
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• 2016

In a construction project, the portion for maintenance costs for a building is considerable compared to the initial construction cost. As such, Life Cycle Cost (LCC) analysis is being increasingly utilized to assess the design value of engineering work in Korea. Additionally, the Public Procurement Service in Korea announced that it will be mandatory for all domestic construction projects to adopt BIM. Furthermore, the paradigm for architectural design has shifted from 2D to 3D, and to BIM, which includes a data management system. Within this background, however, there is currently no adequate BIM-based LCC analysis software and the requirements of cost estimation for repair and replacement cost for a building is not completely adequate in BIM tools such as Revit and Archicad. Therefore, this study suggests a process of cost estimation for repair and replacement (R&R) cost based on IFC data. First, we analyzed existing R&R criteria and defined BIM-based requirements when calculating R&R costs. These requirements were extracted from relevant IFC data. Subsequently, this was saved to a database and a BIM-based database was built for R&R cost estimation. Finally, this database was connected with external databases such as R&R Criteria DB and Cost Information DB to calculate R&R costs. This process is expected to improve upon the traditional process of cost estimation of R&R cost by applying a BIM model. The proposed process can contribute to a further standardizing of BIM-based LCC analysis thru application to initial construction costs, energy costs, and other maintenance costs.

• Korean Journal of Construction Engineering and Management
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• v.21 no.2
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• pp.30-38
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• 2020

Inadequate cost management has widely been recognized as one of the most problematic areas in the Korean construction industry as many believes that public cost references are not reasonably reflecting the market conditions. 'Total Project Cost Management Guideline' developed by Ministry of Economy and Finance(MOEF) to govern public budget control has been identified as one of the main reasons for this problem. This study attempts to thoroughly review 'Total Project Cost Management Guideline' itself and quantitatively analyze the impact of it on project cost during procurement process. Different procurement methods are considered including turnkey & alternative, private contract, qualification examination, and lowest price bidding system in this quantitative impact analysis of 'Total Project Cost Management Guideline'. Analysis results shows that this governmental process works mainly as a constant cost-cutting tool throughout the procurement process.

• Korean Journal of Construction Engineering and Management
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• v.13 no.2
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• pp.3-10
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• 2012

The current enforcement regulation of "Construction Technology Management Act" prescribes calculation standard of environmental preservation cost in construction site. According to this standard, environmental preservation cost is calculated by using the quantity-per-unit costing method or applied fixed rate on direct cost. However, when calculated by using the quantity-per-unit costing method it is few items to put in the budget according to standard of construction estimate and in the case of using the fixed rate on direct cost it is not considering various characteristics of the construction site. Therefore, it is needed a improvement plan of estimating method and management system for environmental preservation cost. In this study, it surveyed the actual state of the environmental preservation cost according to magnitude of project, site location, anti-pollution facilities and etc. over 38 road projects. The research reported in this paper environmental preservation cost was variously distributed over construction sites. Thus it needs to estimating method and management system to consider characteristics of construction site for environmental preservation cost.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.256-260
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• 2004

As a large portion of defence budget are alloted for military facility construction, reasonable budget estimation in the planning stage has been officers' main concerns. However the proper estimation of construction cost is difficult to be carried out due to the absence of systematic criteria. To improve the budget estimation for military facility construction, this study proposes a cost index model which can convert historical cost to current cost. Thus the developed cost index would enhance effectiveness of budget estimation process 3nd support reasonable decision making. This cost index model is developed by analyzing historical cost data with statistical methodology The study is executed by following process. First, factors which affect construction cost for the most are selected by analyzing historical cost data. second, the selected factors are categorized material cost, labor cost and equipment cost, and weights of those factors are calculated by dividing the cost of each factor by total item costs. Last, cost index is developed by using weighted average method.

• Korean Journal of Construction Engineering and Management
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• v.19 no.5
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• pp.43-52
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• 2018

Generally, research on construction cost has been done mostly regarding its direct cost, thus model regarding indirect cost lacks attention. This research seeks to introduce a model to predict on-site overhead cost for apartment construction projects, which constitutes a big portion in Korean construction industry. We devised an equation of 9th degree via curve-fitting, using multiple on-site actual expense data, which can be used to calculate per-progress rate, per-day on-site overhead cost. We further show prospective usage of the model by applying it on construction projects sizing about 30 billion won. Regarding the fact that previous studies could not recognize pattern changes of a total on-site overhead cost, this model is worthy of its conveniency and thoroughness, as well as providing reasonal ground for its derivation in predicting on-site overhead cost of apartment construction projects.