Rajeev Ruparathna

Review of Contemporary Construction Procurement Practices

AbstractProcurement is a key process in a construction project that creates and manages contacts. Procurement activities span from identification of requirements to project closeout, making it a perfect mode for integrating organizational strategic directions. Lately, the strategic importance of procurement has been widely acknowledged by academics as well as industry professionals. Construction procurement is a complex process with a large number of available options and directions. Ad hoc statistics show that modern initiatives such as sustainability, life-cycle costing, and standardization are getting integrated with procurement. However, there is no unified view in the construction industry on procurement as a project process. This paper presents a comprehensive review of traditional and emerging procurement practices in the construction industry. The current procurement practices are analyzed by separating into three segments; processes, methods, and policies. Furthermore, strengths and weaknesses of...

Sustainability assessment framework for low rise commercial buildings: life cycle impact index-based approach

The building industry has regularly been criticized for resource exploitation, energy use, waste production, greenhouse gas emissions, and impacts on the landscape. The growing population demands more built environment to accommodate the socioeconomic wellbeing. Adopting conventional construction practices would continue the aforementioned issues. Therefore, it is important to integrate life cycle thinking into building construction to minimize its social, environmental, and economic impacts. The objective of this study is to assess the life cycle impact of commonly used wall–roof systems for low rise commercial building construction in Canada. A framework is developed to assess different building alternatives using the triple bottom line of sustainability. Identified environmental and socioeconomic impact indicators are eventually aggregated to develop a life cycle impact index. Material quantities of six wall–roof combinations for a single-storey commercial building were obtained from industrial partners. State-of-the-art life cycle assessment software is used to assess the life cycle impacts of different wall–roof systems. To accommodate decision makers’ preferences of sustainability, wall–roof combinations are assessed for three potential scenarios namely, eco-centric, neutral, and economy-centric using multi-criteria decision analysis. The framework has also been implemented on a case study of low rise building in Calgary (Alberta, Canada) to evaluate its practicality. The study results revealed that the concrete–steel building is the most sustainable alternative in neutral and economy-centric scenario while steel–wood building is the most sustainable building in eco-centric scenario.

Motivating Workers in Construction

The study of the motivation of construction workers is limited to a relatively small body of knowledge. Although there is considerable research available regarding motivation and productivity, few researchers have provided a comprehensive analysis on the motivation of construction workers. The research stated that productivity in construction has not improved compared to other industry sectors such as manufacturing. This trend has been echoed in publications throughout the past five decades, and suggested that motivation is one of the key factors impacting productivity. This paper offers a comprehensive review of the published work that directly links the key words—construction and motivation. The findings have been presented in five themes, that is, motivation models, environment and culture, incentives and empowerment, and worker management. This paper concludes with two methods suggested by previous researchers to improve motivation of construction workers: (1) relevant worker incentives (intrinsic or extrinsic) and (2) improved management practices, specifically regarding communication with workers.

Rethinking investment planning and optimizing net zero emission buildings

Increased awareness of climate change has precipitated more stringent mitigation targets. Public sector institutions in Canada are committed to becoming carbon neutral to attain a leadership position in climate change mitigation-related initiatives. Recent statistics reveal that buildings account for the majority of the corporate carbon footprint of public sector institutions. Hence, there is an increasing interest towards developing net zero energy and net zero emission buildings to comply with climate action targets. With limited financial resources, public sector institutions must optimize investments into building energy retrofits by considering lifecycle cost (LCC), overall energy performance, and related greenhouse gas (GHG) emission. The aim of this paper is to develop an investment planning approach for net zero emission buildings (NZEB). First, an investment planning approach for NZEB is proposed. A typical recreational centre building in British Columbia, Canada, was used as the archetype to demonstrate the concept. Second, innovative and proven building energy retrofits were analysed using energy simulation software to assess the impact on energy consumption reduction, GHG emissions, and LCC. Third, impacts of geographical location, tariff regimes, and grid emission factors on energy retrofits were studied by locating the same building in other provinces of Canada. This study revealed that net zero energy investment has a strong correlation to the grid emission factor. The proposed approach in this paper will assist building managers and owners in retrofitting and budget planning.

Assessment of the level of service (LOS) of public recreational centre buildings : an uncertainty based approach

The federal sustainable development strategy (FSDS) for Canada advocated that public sector operations should aim at shrinking the environmental footprint while enhancing social benefits. In this quest, improving the sustainability performance of public buildings becomes a key constituent since buildings are responsible for the highest portion of the corporate GHG emission and energy usage of public entities. Moreover, public buildings are an important constituent of the socio-economic environment of a local region. Hence, there is a need for improving the sustainability performance of the future and existing public buildings. Currently, various innovative methods are used by federal, provincial and municipal entities to improve the sustainability performance of public buildings. However, asset management of building has been overlooked from the above studies. There is a lack of comprehensive methods to assess the level of service (LOS) of a building that is crucial for life cycle asset management. To address this problem, this paper proposes an approach to calculate the LOS of a recreational centre building operated by municipal government. Firstly, a LOS framework is formulated for recreational centre building by taking into consideration the key aspects. Secondly, a fuzzy synthetic evaluation method is used to assess the building performance. Thirdly, a case study was conducted to validate the proposed methodology. Results from this approach provide detailed information about the performance of the building assets. This approach facilitates in identifying areas that require immediate attention for improvement. This study provides a novel approach to life cycle asset management of public sector buildings.

Energy rating system for climate conscious operation of multi-unit residential buildings

Residential sector accounts for 17% of domestic energy use and 14% of the greenhouse gas emissions in Canada. Improving the energy performance of the Canadian residential building stock is vital in achieving climate action goals. A comprehensive review of popular building energy rating systems noted their lack of life cycle thinking. The scope of the popular rating systems is limited to operational performance, ignoring the condition of the assets. This paper proposes a condition assessment framework for the energy system of existing multi-unit residential buildings (MURB), which combines the concepts of asset rating and operational rating. Indicators were identified to define energy, environmental, economic, and asset performance of MURB. A life cycle assessment was conducted to quantify the overall environmental impacts of energy technologies from point of generation. A fuzzy logic-based approach was used to overcome the challenges due to data uncertainty and impreciseness. A case study was conducted for a residential building at UBC Okanagan, Canada. The weights at indicator level and category level were defined based on stakeholder consultation, while also considering different decision scenarios. A fuzzy rule-based approach was used to combine the different performance categories to obtain an overall condition rating. The results indicate that the performance of the case study building can be rated as “good” under operational, asset, and overall categories. The findings of this research can be used to improve the asset and operational management strategies in existing buildings and can inform the key stakeholders during the operational phase of the buildings.