Implementing BIM for quantity surveying services
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ollowing the emergence of BIM, there has been a burgeoning increase in its implementation. As a matter of fact, BIM has been claimed to offer a significant advantage in improving the estimating practice, often prone to errors and inaccuracies. While the continued increase in the adoption of BIM globally has been speculated to threaten QS services, studies have shown that BIM, on the contrary, has the potential to revolutionize the QS practice by relieving the tediousness of tasks, thus enhancing job performance and providing more time to devote to other value-added services. Nevertheless, implementation of BIM for QS practices has been a bit slow. While there is certainly no shortage of information about BIM and quantity surveying practices, there is little yet to guide cost-consulting firms on its practical implementation. The goal of this study was to provide answers to lingering questions surrounding successful implementation of BIM for quantity surveying services, and to understand how BIM impacts the practice. To achieve this, three BIM experts in the QS field reviewed literature and conducted semistructured interviews. The parametric modelling in BIM is said to facilitate the creation of a relationship among elements, and includes the specification and properties of individual elements and objects, potentially enabling the extraction of comprehensive and accurate information from the model, which can be directly used for costing. Thus, estimators use a variety of options CLICK HERE to return to Table of Contents
to leverage BIM for quantity take-off and to support estimating. These methods range through a direct interrogation model, an indirect interrogation model and to BIM Quantity Take Off. The direct interrogation model allows schedules of quantities produced from the model to be downloaded into Excel or other estimating software, and then priced. The indirect model involves linking BIM components directly to estimating software by linking a ‘5D Cost Library’ or an estimating package to BIM via plug-in or third-party tools. In the case of the BIM Quantity Take Off method, specialized quantity take-off tools (such as Autodesk QTO, Exactal Cost X, Innovaya, etc.) are used to import data from various BIM tools. The most sophisticated option is working within the 5D BIM environment. According to Exactal Inc., the QS/estimator can participate in data exchange from the outset, rather than working in isolation, to offer cost advice or take-off quantities for a project; however, there has been limited use of the 5D BIM globally, due to lack of use of a single BIM model. From literature and experts’ responses, identified critical barriers inhibiting adoption of BIM include: high cost of implementation, lack of trained professionals, no demand for BIM, lack of enabling environment (government policies & legislations), and social and habitual resistance to change. Also, this study revealed that while literature envisaged a high impact of BIM on the mode of QS practices
– including a threat to the future of the profession – responses from experts show there was little difference in how services were rendered. Respondents did agree on how BIM improves their efficiency in service delivery because, unlike in traditional estimating, quantities were extracted automatically. Models have now been validated using Solibri and standardization has become paramount. Besides, the collaborative environment provided by the BIM process has been established to influence practices and redefine the professional boundaries in the AEC industry. Also, adopting BIM provides these organizations additional opportunities, such as providing information management services on projects. Furthermore, analysis of responses received confirmed that using BIM for cost consulting services could be frustrating at the initial phase, but does improve over time, hence the adoption plan that suggests following these three
Fall 2019 | www.ciqs.org | CONSTRUCTION ECONOMIST | 19
