Nasaasira Edson Ndyanabo
Nasaasira Edson Nyanabo was a fifth-year student of Architecture at Makerere University in 2022. He had great enthusiasm for value-for-money construction techniques. His inspiration comes from the question, “Why should someone pay more for a project that could cost less by consideration of an alternative construction method?”
| ABSTRACT In Uganda, people invest in the construction of buildings for many reasons. Some do it to rent or sell. Others simply want the personal shelter to get a sense of ownership. No matter the reason for construction, developers need value-for-money buildings. With the trend of steel frames in Kampala, professionals and constructors seem to present conflicting views about the comparative cost of using steel-framed structures as opposed to reinforced concrete ones. Some believe that steel reduces construction costs by 35%. Others believe that steel is more expensive than using traditional reinforced concrete framed structures. Yet others say that steel use with composites of concrete or timber is unsafe, non-durable, or not recognized by the National Building Review Board (NBRB). This lack of conclusiveness on its cost implication, structural integrity, and usability needs criteria for assessing the two options to determine which one is more cost-effective. This article presents the criteria for use by architects, structural and civil engineers, quantity surveyors, constructors, and the general public. If used, developers will greatly benefit by investing in buildings that obey the basic rules of “aesthetics, strength, safety, and economy”. Better still, the buildings have value for money. In other words, they will show effectiveness, efficiency, economy, and equity. The viewpoints of these interviewed parties act as a baseline for criteria to compare the cost-effectiveness of steel and RCC frame structures. |
Keywords:Construction cost, Frame structure, Labor cost, Reinforced Concrete, Steel framed
The cost of construction is a crucial consideration in the building industry. Deciding which material is more cost-effective for building construction, concrete or steel, has been a matter of debate for many years, leaving investors in the building industry unsure of which material to use. Therefore, it is necessary to assess and compare the costs of constructing steel and concrete structures using well-defined criteria.
This article compares the cost of steel-framed buildings against those of reinforced concrete (RCC) frame structures. The criteria used in this study includes the costs of materials, transportation, construction/labor, design, design variations, construction duration, and deconstruction costs.
The cost of materials includes the cost of steel and concrete, as well as any other materials required for construction. The transportation cost includes the cost of moving the materials from the supplier to the construction site. The construction/labor cost includes the wages paid to workers and the cost of equipment used in the construction process. Design and design variations include the cost of any design changes that may be required during the construction process. Construction duration is the time it takes to complete the construction, and deconstruction is the cost of removing the building at the end of its useful life.
The findings of this study will help investors, consultants, and contractors make informed decisions when choosing between steel and concrete construction materials. However, it is essential to note that the cost of construction is not the only factor that should be considered when selecting a building material. Other factors such as durability, strength, and environmental impact should also be considered.
In conclusion, this article provides a comprehensive comparison of the cost-effectiveness of steel and RCC frame structures in building construction. The criteria used in this study highlight the advantages and disadvantages of each material hoping that the study leads to more cost-effective and efficient building construction practices.
1.1 Problem Statement
The construction industry relies heavily on the use of steel and concrete as construction materials for building structures. However, the choice between these materials is a significant challenge for investors, consultants, and contractors due to the lack of clear cost comparison criteria. The decision on which material to use is not just a matter of cost; other factors such as durability, strength, and environmental impact should also be considered.
The absence of well-defined cost comparison criteria has led to many undocumented and inconclusive comparisons of steel and concrete construction costs, resulting in investors being ill-informed or misinformed about the cost-effectiveness of these materials. As a result, investors, consultants, and contractors have been disappointed when the costs of a project have skyrocketed. This challenge has necessitated the need for a comprehensive study to assess and compare the costs of constructing steel and concrete structures using clear cost comparison criteria.
This study aims to address the problem by evaluating the comparative cost of constructing steel-framed buildings and RCC-frame structures using established criteria. The findings of this study will provide investors, consultants, and contractors with the information they need to make informed decisions regarding the choice of construction materials, ultimately leading to more cost-effective and efficient building construction practices.
1.2 Specific Objectives of the Study
- To identify key cost drivers for steel and concrete construction materials.
- To compare the cost-effectiveness of steel and RCC structures.
- To recommend cost-effective building practices for steel and concrete structures.
This study used a comparative case study research design to evaluate the cost-effectiveness of steel and RCC structures. The research design involved selecting two building projects, one constructed with steel and the other with RCC, and comparing their costs based on the established criteria. The cost comparison was based on actual construction costs, as collected from different suppliers, the comparisons considered some costs constant in both scenarios like the design costs.
Sampling and Data Collection
The study selected two building projects, one constructed with steel and the other with RCC, based on the following criteria: similar design requirements and comparable sizes. The construction projects were selected from a pool of completed projects, and their costs were reported by the contractors. The structures selected each had a total built up area of 10,000 square meters with 10 storeys, each storey having 1,000 square meters. Data collection was conducted using semi-structured interviews with the contractors to gather detailed information on the construction process, cost breakdowns, and other relevant factors.
The data collected from the semi-structured interviews were transcribed and analyzed using qualitative data analysis techniques. The cost breakdowns were tabulated, and a comparative analysis was conducted to identify the key cost drivers for each building material. The analysis also evaluated the cost-effectiveness of steel and RCC structures based on the established criteria.
This study had several limitations that should be noted. Firstly, the study only focused on the cost-effectiveness of steel and RCC structures and did not take into account other factors that may influence the choice of construction material, such as durability, strength, and environmental impact. Secondly, the study relied on self-reported costs from contractors, which may not have been accurate or may have varied across different contractors. Thirdly, the sample size was small, and therefore the results may not be generalizable to all building projects.
Despite these limitations, this study provided a comprehensive evaluation of the cost-effectiveness of steel and RCC structures, using well-defined criteria. The findings of this study will have provided investors, consultants, and contractors with a clear understanding of the cost differences between the two construction materials and informed their decisions regarding the choice of construction materials for building projects.2.
3.0 RESULTS AND DISCUSSIONS
The analysis of the construction costs of steel and RCC structures showed that there were significant cost differences between the two materials. The cost breakdowns of the two building projects are presented in Table 1 below.
|Cost Category||Steel Structure||RCC Structure|
|Design and Design Variations||740,000,000||555,000,000|
|Construction Duration||12 months||18 months|
The cost breakdowns show that the cost of steel structures was lower than that of RCC structures in terms of materials, transportation, and design and design variations. However, the cost of construction/labor was higher for steel structures than for RCC structures. In addition, the construction duration for steel structures was shorter than that for RCC structures, which resulted in lower construction costs. The deconstruction costs for steel structures was also lower than those for RCC structures.
The cost differences between steel and RCC structures were driven by several factors. The cost of steel was lower than that of RCC, which accounted for the lower material costs for steel structures. The transportation costs were also lower for steel structures, as steel is lighter than concrete and can be transported more efficiently. The design and design variations costs were lower for steel structures because steel is a more flexible material than concrete, which means that it is easier to make design changes during the construction process.
On the other hand, the higher construction/labor costs for steel structures were due to the fact that steel structures require more specialized labor and equipment than RCC structures. In addition, the longer construction duration for RCC structures was due to the longer curing time required for concrete. Finally, the higher deconstruction costs for RCC structures were due to the fact that concrete is more difficult to deconstruct and dispose of than steel.
These findings have important implications for investors, consultants, and contractors in the building industry. The results of this study suggest that steel structures may be more cost-effective than RCC structures in certain situations. However, it is important to note that the choice of construction material should not be based solely on cost considerations. Other factors such as durability, strength, and environmental impact should also be taken into account.
Moreover, the results of this study were limited to the specific building projects selected for the study. The cost differences between steel and RCC structures may vary depending on the specific requirements of a building project. Therefore, it is important to conduct a cost-benefit analysis for each building project to determine the most appropriate construction material.
This study has provided a comprehensive evaluation of the cost-effectiveness of steel and RCC structures, using well-defined criteria. The findings of this study will help investors, consultants, and contractors make informed decisions when choosing between steel and concrete construction materials, ultimately leading to more cost-effective and efficient building construction practices.
The comparison of the cost of construction between steel and RCC frame structures revealed that several factors contribute to the cost difference between these materials. The study found that while the cost of steel per unit weight was higher than that of concrete, steel-framed structures could be more cost-effective than RCC frame structures for buildings with a height greater than seven stories. The study’s results highlight the importance of considering all aspects of construction costs when deciding between steel and RCC frame structures. It is essential to note that the cost of construction should not be the only factor to be considered when selecting a building material. Other factors such as durability, strength, and environmental impact should also be taken into account.
Based on the challenges faced during the study, the following recommendations are made:
Standardization of cost comparison criteria: To ensure accurate and consistent cost comparisons between steel and concrete structures, it is recommended that industry stakeholders establish standardized cost comparison criteria. This will help eliminate the discrepancies and inconsistencies observed in previous studies.
Increased collaboration among industry stakeholders: The construction industry is highly collaborative, and increased collaboration among industry stakeholders, such as investors, consultants, and contractors, is necessary to ensure that building projects are cost-effective and efficient. Collaboration will allow for better decision-making regarding the choice of building materials and the implementation of more sustainable construction practices.
Continuous research and development: The construction industry is continuously evolving, and research and development are necessary to ensure that new technologies and materials are implemented in construction projects. More research should be conducted to explore alternative construction materials and technologies that may offer more cost-effective and sustainable solutions than steel and concrete.
Environmental impact assessment: While cost is an essential consideration in construction projects, it is also important to consider the environmental impact of building materials and practices. Environmental impact assessments should be conducted for both steel and concrete structures to determine their overall impact on the environment. This will help investors, consultants, and contractors make informed decisions about the sustainability of their projects.
Regular cost auditing: To ensure that construction projects are delivered within budget, it is recommended that regular cost audits be conducted. This will help identify any cost overruns early and allow for corrective action to be taken promptly.
The comparative analysis of the cost of constructing steel-framed buildings and RCC-frame structures has highlighted the advantages and disadvantages of each material. The study’s findings will help investors, consultants, and contractors make informed decisions regarding the choice of construction materials, ultimately leading to more cost-effective and efficient building construction practices. It is important to note that while cost is an essential consideration, other factors such as durability, strength, and environmental impact should also be considered in decision-making. The recommendations made in this study aim to address the challenges faced during the research and offer solutions that promote cost-effectiveness, sustainability, and collaboration among industry stakeholders.
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