Abstract: This paper examines the relationship between innovation and productivity improvement in the construction industry. It is argued that this relationship is not well understood due to lack of in-depth understanding of innovation in construction. To overcome this obstacle, the authors present a multi-dimensional innovation classification system which aims at better defining and classifying what is meant by innovation in construction. The use of this classification system is demonstrated by applying it to a database of 500 innovations reported by the construction alliance, the Stronger Christchurch Infrastructure Rebuild Team. The results clearly demonstrate the diversity of types, degree of novelty and performance improvement benefits among construction innovations. Such diversity means that the impact of the reported innovations on productivity and performance are of different levels of significance. The classification system developed in this study can be used by construction organisations and alliances in the future to develop more detailed methods of calculating innovation performance indicators, based on the innovation type, novelty and benefits factors. By using this system, they can also put in place mechanisms to influence the types of innovation developed in their projects with the aim of maximising their productivity performance.
Abstract: Sustainable development of the built environment in developing countries is a major challenge in the 21st century. The use of local materials in construction of buildings is one of the potential ways to support sustainable development in both urban and rural areas. Building with Compressed Earthen Blocks (CEBs) is becoming more popular due to their low cost and relative abundance of materials. The proposed Green-Compressed Earth Block (GCEB) consists of ordinary CEB ingredients plus Banana fibers, which will be the focus of this study. Banana fibers are widely available worldwide as agricultural waste from Banana cultivation. Banana fibers are environmentally friendly and present important attributes, such as low density, light weight, low cost, high tensile strength, as well as being water and fire resistant. This kind of waste has a greater chance of being utilized for different application in construction and building materials. This focused on the use of banana fiber and its effect on the compressive and flexural strength in CEB. The deflection at the mid-span of the blocks studied was calculated using the Linear Variable Differential Transformer (LVDT). The results of this study will highlight general trends in the strength properties of different soil mixes for CEBs. These efforts are necessary to ensure that GCEB technology becomes more widely accepted in the world of building materials and is considered a reliable option for providing low-cost housing.
Abstract: One of the key objectives of contemporary urban design is to ensure the quality and activity within urban public spaces. Presented as a progressively emerging paradigm in this process, the effects of urban climatology are increasingly elucidating the need for further climate responsive environments. Moreover, this interest is one that shall increase along with the progression of climate change effects upon outdoor environments. Nevertheless, it is often that climatic assessments lack bottom-up climatic indicators, tools and practical benchmarks. As a result, this obstructs local decision making, and practices of localised adaptive design. In an effort to address such discrepancies, this paper launches a framework of international precedents of built and conceptual projects that address thermal comfort levels in public spaces. This organisation will be cross-referenced with theory that supports its structure and typological division. With Auckland as the focal case study, the solutions that are extracted from the framework will be scrutinised in order to shape new potential measures, and launch new considerations in Auckland’s local policy and design guidelines. In this way, microclimatic concerns are hence framed into an opportunity to potentiate the use and longevity of Auckland’s public realm.
Abstract: New Zealand state housing includes a significant portion of problematic buildings constructed after the public housing scheme launched in 1936. Most of these houses are still uninsulated, thus, cold, draughty, mouldy, and progressively decaying; however, as they are fundamental elements of the country’s culture, society, and environment, and are built with good quality materials and sound construction, they are suitable candidates for effective energy upgrades. This paper presents findings of a study on problems and opportunities of retrofitting the state houses built between 1940 and 1960 in the Auckland region. It advocates strategic national policies and initiatives for retrofitting, based on more challenging performance thresholds. The research defines and virtually implements an incremental intervention strategy including different retrofit packages for a typical 1950s stand-alone house. Indoor and outdoor environmental parameters were monitored over a year, and data used to establish a base case for thermal simulation. The upgrade packages were then modelled to assess their impact on the house’s thermal performance, comparing heating requirements and comfort of various insulation and ventilation options. The paper reports on effective ways of preserving the integrity of such a house, while improving its thermal performance to the EnerPHit standard, and discusses the benefits of introducing this holistic approach into New Zealand retrofit practice.
Abstract: The building construction industry faces challenges, such as increasing project complexity and scope requirements, but shorter deadlines. Additionally, economic uncertainty and rising business competition with a subsequent decrease in profit margins for the industry demands the development of new approaches to construction management. However, the building construction sector relies on practices based on intuition and experience, overlooking the dynamics of its production system. Furthermore, researchers maintain that the construction industry has no history of the application of mathematical approaches to model and manage production. Much work has been carried out on how manufacturing practices apply to construction projects, mostly lean principles. Nevertheless, there has been little research to understand the fundamental mechanisms of production in construction. This study develops an in-depth literature review to examine the existing knowledge about production models and their characteristics in order to establish a foundation for dynamic production systems management in construction. As a result, a theoretical framework is proposed, which will be instrumental in the future development of mathematical production models aimed at predicting the performance and behaviour of dynamic project-based systems in construction.
Abstract: Several studies have documented benefits of prefabrication system (prefab) compared to the traditional building system (TBS). However, the documented benefits have been anecdotal or fragmented with reports of isolated case study projects. Few studies have looked at the objectively quantified benefits from statistical significance point of view and across building types in New Zealand. This study contributes to filling this knowledge gap by analyzing cost and time-savings, and productivity improvement achievable by the use of prefab in place of the TBS. Records of completion times and final contract values of 66 building projects implemented using prefab in Auckland were collected. The building types included commercial, houses, apartments, educational, and community buildings. The project details included final contract sums, completion dates, gross floor areas, and number of floors. Based on these details, the equivalent completion times and the final cost estimates for similar buildings implemented using the TBS were obtained from the Rawlinsons construction data handbook and feedback from some designers and contractors. Marginal productivity outcome for each building project was computed as the product of the cost and time-savings achieved using the prefab. Results showed that the use of prefab in place of TBS resulted in 34% and 19% average reductions in the completion times and costs, respectively. This also translated to overall 7% average improvement in the productivity outcomes in the building projects. Univariate ANOVA-based hypothesis test results showed that ‘building type’ had no significant effects on the cost and productivity improvement outcomes, but had significant effect on the time savings analyzed in the case study projects. The greatest productivity gain of 11% was achieved in house projects. These evidence-based results could guide optimized use of prefab for specific building application. The hypothesis-testing outcome provides insights on one of several potential influences on prefab improvements, which will be analyzed in subsequent research.