Model Estimation of the Whole Life Cost of a Building With Respect to Risk Factors

Abstract

The paper deals with estimating the life cycle cost and the whole life cost of a building. An original model for estimating the life cycle cost and the whole life cost of a building which allows the quantification of the increase in costs resulting from the incurred and assessed risk is presented. The proposed model consists of two basic parts: module I evaluating the impact of identified risk factors on individual element of the life cycle cost, and module II allowing to assess life cycle cost including the risk factors selected in module I. In module I the model of fuzzy inference of Mamdani was used. The structure of module II is based on the theory of possibilities and fuzzy sets. The operation of the model is presented on the example of an office building.

Original Model for Estimating the Whole Life Costs of Buildings and its Verification

“…A set of calculation formulas, thanks to which it is possible to calculate economic indicators: LCC, WLC, LCEAC and ΔR LCC , was presented and discussed in detail in the following authors' publications [10,11,18,19]. The examples below include only the most important equations.…”

“…The authors have therefore attempted to develop a model for estimating the whole life costs of buildings enabling the quantification of cost addition for risk, which would allow the investor to compare buildings in terms of a number of economic criteria: life cycle costs (LCC -when the investor is not able to record incomes), whole life costs (WLC -when, in addition to bearing the costs during the life cycle of the building, the investor is able to record incomes), life cycle equivalent annual costs (LCEAC -when the durations of the operation phase differ) and cost addition for risk (ΔR LCC -expressed as a difference in currency units between the life cycle cost of a building which takes into account the impact of risk and the life cycle cost of a building that does not include this impact). The subsequent stages of the development of the model are described in numerous publications by the authors [10,11,12,13,17,19].…”

Probabilistic and Fuzzy Approaches for Estimating the Life Cycle Costs of Buildings under Conditions of Exposure to Risk

“…Taking into account the above, the authors attempted to develop a complex model for estimating the whole life costs of buildings, which enables the quantification of cost addition for risk, and which allows the investor to compare buildings in terms of a number of economic criteria, namely: life cycle costs (LCC-when the investor cannot record incomes), whole life costs (WLC-when, in addition to incurring costs in the phases of the building life cycle, the investor will also be able to record incomes), life cycle equivalent annual costs (LCEAC-when the durations of the exploitation phase differ) and cost addition for risk (∆R LCC -expressed as a difference in currency units between the amount of the life cycle cost of a building which takes into account the impact of risk, and the value of the life cycle cost of a building that does not respect this influence). The authors based the assumptions of the model on the fuzzy approach, and the subsequent stages of the model development are treated by their numerous publications [17][18][19][20], including the publications on verification studies investigating the correctness of the model's operation [21,22].…”

Identification of factors shaping tender prices for lightweight

“…Successful completion of a construction project means that its completion has been completed within the assumed budget, at the scheduled time, in accordance with the expected quality, and taking into account all investor requirements. In the literature, many studies can be found regarding the analysis of construction projects due to their costs (Juszczyk, Leśniak & Zima, 2018;Wieczorek, Plebankiewicz & Zima, 2019), time (Ibadov & Kulejewski, 2015;Krzemiński, 2017), organizational aspects (Hoła, 2015;Kozlovska, Mackova & Spisakova, 2016;Lendo-Siwicka, Połoński & Pawluk, 2016;Nowotarski, Pasławski & Matyja, 2016;Grzyl, Miszewska-Urbańska & Apollo, 2017;Nowogońska & Cibis, 2017;Hanak & Korytarova, 2018), safety issues (Hoła & Szóstak, 2015), or the use of innovative solutions in construction fi led (Mrówczyńska, 2011;Kapliński, 2018). Yet, it is the calculation of costs that is one of the most important aspects of construction projects, both from the investor's and contractor's point of view.…”