The cost of producing one cubic meter of concrete structure, depending on the structure’s shape, type, and complexity, can be variously high. The cost of concrete, reinforcement, formwork, and labor ratio varies. But unlike the cost of concrete and reinforcement, which tend to be similar in the terms of the conditions of a particular construction project, the cost of formwork and work with it are different for different contractors. It often depends on the appropriateness of the formwork system used, the optimal placement of the formwork sets, the minimization of downtime, and the efficiency of the carpenters’ work. Formwork modeling in the construction preparation phase intervenes in this planning area, where construction sources are defined and quantified, and the time course of their deployment is determined. The current paper deals with optimizing formwork selection and deployment in concrete structure execution. Even if several requirements must be considered when selecting and modeling the formwork (e.g., construction time, quality of concrete structure, etc.), an effort to minimize the cost of formwork, and thus construction cost, plays the most significant role. A dynamic model for effective and optimal planning of formwork in construction projects, including formwork cost analysis, is presented in the paper. The included case study demonstrated the planning of the formwork through a software application developed based on the computational algorithm of the dynamic model presented. A case study is presented in the article as a research method. An office building with five above-ground floors and one underground floor was chosen for the case study. To solve the case study, the formwork for horizontal structures (i.e., beams and slabs) is considered. The goal of the case study is to identify research questions and apply time and cost optimization to a selected specific building.

The aim of the paper is to emphasize the need for logistics planning in prefabricated construction in Slovakia. A construction contractor can achieve profit and efficiency of a construction project through well-managed resource logistics. Moreover, it helps to ensure the competitiveness of prefabricated construction compared to traditional on-site construction. In the case study of a wood-based family house, the construction cost and the transport cost are analysed in relation to available logistics chains Three variants of wood-based construction systems are adopted in the study: the column-beam construction system, the construction system based on Structural Insulated Panels (SIPs) and the panel construction system. The results of the study found that the transport cost does not represent a large share of the total construction cost of the wood-based family house. This applies to all three variants of the construction system. A well-planned logistics of resources - people, materials, machines - can help to achieve an efficient and rational construction cost and construction time of a project. Thus, a client of a wood-based prefabricated building does not have to worry that the transport cost related to the transport of large, prefabricated components will make the construction of the building markedly more expensive.

By reducing construction times and thereby shortening the times of construction site operation, it is possible to contribute to ensuring the social, economic, and environmental pillars of sustainability, which are necessary to meet the 2030 climate target plan set by the European Commission. This paper deals with an analysis of the time of site operation in construction of residential buildings. The site operation time in construction of fourteen residential buildings in Slovakia was examined. The research offers findings that can help clients make more rational decisions about the duration of construction site operation they request from contractors in construction contracts. Defining the mathematical dependence between the size of building and needed time of construction site operation in the pre-project planning phase was one of the results of this analysis. Based on the relationship expressed in this way, contractors can predict whether it will be possible to obtain a score in an environmental assessment of a building by minimizing undesirable effects of the construction site (such as dust, noise, and vibrations) through reducing the time of construction site operation. The study also produced a methodology in the form of steps or actions for the possible reduction of construction site operation time. The equation of dependence that resulted from the present study may be a good basis for planning a sustainable construction site that only affects its environment during the necessary construction time.

INTEGRATED ASSESSMENT OF BUILDINGS QUALITY IN THE CONTEXT OF SUSTAINABLE DEVELOPMENT PRINCIPLES

The issues that the construction sector currently faces with regard to productivity and efficiency are well acknowledged. In the construction industry, there is plenty of space for efficiency to improve, with an increasing number of new tools and methods coming out. One of the solutions to increase efficiency is the application of modern methods of construction. The modern methods of construction, especially dry construction techniques, are developing so that there is a larger volume of high-quality production with a shorter time for procurement. Not only in the construction of skeletons but also in the finishing works, it is a huge advantage if there are implemented techniques that eliminate traditional wet construction works and thus shorten the construction time. On the other hand, however, the question of efficiency in relation to their costs is raised. Based on theoretical and empirical research, the aim of this study is to demonstrate the potential of modern dry construction systems and solutions for finishing works, especially in relation to the construction time and construction cost. For this purpose, an expert knowledge system, named the complex COMBINATOR, was developed. Through a set of simulations with the help of the COMBINATOR, the effects of different combinations of dry construction systems and techniques (DCSTs) and traditional wet construction systems and techniques (WCSTs) on the time and cost of finishing construction works were measured. Based on the results of simulations carried out through the complex COMBINATOR with an inference engine that enabled these simulations, the potential of dry construction techniques for the implementation of finishing works in the construction of residential buildings was demonstrated. Without simulating the effects of the individual technological models for finishing construction works in relation to two of the most important parameters of construction projects, namely time and cost, it would not be possible to obtain the resulting parameters for different combinations of DCSTs and WCSTs from the study presented. Therein lies the huge importance of the presented knowledge system for deciding on the benefits of DCSTs.