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Automation in Construction
Volume 127, July 2021

Sheida Shahi, Patryk Wozniczka, Chris Rausch, Ian Trudeau, Carl Haas


Adaptation of existing building stock is an urgent issue due to aging infrastructure, growth in urban areas and the importance of demolition mitigation for cost and carbon savings. To accommodate the scale of implementation required, there is a need to increase the efficiency of current design and production processes. Computational methodologies have proven to increase design efficiency by generating and parsing through myriad design options based on multivariate (e.g., spatial, environmental, and economic) factors. Modular Construction (MC) is another approach used to increase efficiency of both design and production. This paper combines these approaches in a novel methodology for generating modular design options for extensions of existing buildings (an efficacious form of building adaptation). The methodology focuses on key architectural design metrics such as energy use, daylighting, life cycle impact, life cycle costing and structural complexity, whereby a set of Pareto-optimal exploratory design options are generated for evaluation and further design development. A functional demonstration is then carried out for the extension of Ken Soble Tower in Hamilton, Ontario. The contribution of this research is the efficient development and evaluation of design options for improving existing residential infrastructure in order to meet required energy improvements using modular extensions.

Sustainable Cities and Society
Volume 63
December 2020

Sheida Shahi, Mansour Esnaashary Esfahani, Chris Bachmann, Carl Haas

Building adaptation encompasses a range of construction activities that improve existing building conditions and extend the effective lives of buildings. The scopes of building adaptation projects vary, and may include rehabilitating failing structures, improving environmental performances, and changing functional uses. In order to address multiple aspects of building adaptation, different terminologies are used in the literature and in practice, including refurbishment, retrofitting, rehabilitation, renovation, restoration, modernization, conversion, adaptive reuse, material reuse, conservation, and preservation, amongst others. These terminologies are often used interchangeably with overlapping definitions, causing a lack of clarity in the addressed scope of work. An extensive literature review of terminologies related to building adaptation was conducted and the most common and applicable terminologies were identified. Recent definitions, applications, and scope for the identified terminologies are reviewed. Based on this classification, a definition framework is developed enabling precise categorization of building adaptation projects, and application is demonstrated in multiple case studies. The proposed definition framework is a valuable reference for future researchers and practitioners to clearly and consistently define the scope of work in their building adaptation projects, and thus avoiding the high costs arising from codes, specifications, and project descriptions that confuse these definitions.

Energy Performance and LCA-driven Computational Design Methodology for Integrating Modular Construction in Adaptation of Concrete Residential Towers in Cold Climates

2020 Proceedings of the 37th ISARC, Kitakyushu, Japan

Sheida Shahi, Patryk Wozniczka, Tristan Truyens, Ian Trudeau and Carl Haas


Adaptation of dated residential towers is an urgent issue due to aging housing infrastructure and growing demand for affordable housing. Computational design methodologies have the potential for facilitating optimized design strategies driven by improved energy performance and reduced life-cycle carbon emissions. Modular Construction (MC) can also increase efficiencies in the design and implementation of building adaptation projects and minimize construction waste. The application of MC in the adaptation of existing buildings is gaining interest with improvements to MC technologies and processes, as well as large-scale adoption. There are currently no frameworks for the integration of MC in the adaptation of complex buildings driven by energy performance and Life Cycle Analysis (LCA). To address this gap, a framework is developed for integrating computational design methodologies and design optimization using energy use and LCA for improving overall building adaptation processes. The building adaptation of Ken Soble Tower in Hamilton, Ontario, is used for the functional demonstration. A set of extension modules are considered, and various adaptation scenarios that conform to set design constraints are evaluated for energy use and LCA. The results of this study prove the practicality of using computational design methodologies for the integration of MC in the adaptation of concrete residential towers and can promote the efficiency of improving existing residential infrastructure.

Journal of Cleaner Production Volume 324, November 15 2021

Beatriz C.Guerra, Sheida Shahi, Aida Mollaei, Nathalie Skaf, Olaf Weber, Fernanda Leite, Carl Haas

Construction consumes more than 3 billion tons of raw materials globally each year. Adopting circular economy principles can help reduce waste and save more than $100 billion per year by improving construction productivity. This study’s overarching objective was to investigate the state of adoption of circular economy principles in the construction sector. A multiple case study approach was used, and adoption opportunities were investigated in a global scan of 81 companies implementing circular economy principles in the construction industry. A knowledge framework with 33 attributes was developed to classify the companies, and their initiatives were analyzed in terms of overall focus, lifecycle operations, and business operations. These companies were categorized into seven identified business types, and their adoption of nine major circular business models was evaluated. Opportunity gaps and areas for improvement were identified, and steps for accelerating the shift towards a circular economy in construction were suggested. Furthermore, specific opportunities and prospects were discussed for implementing a circular economy in the United States, Canada, and the European construction industries. Notably, this study fills a gap in the literature by providing empirical evidence of the state of adoption of circular economy principles in the construction sector. Presented findings can help both academics and industry practitioners understand the current state of adoption of circular economy principles by construction companies and accelerate steps towards circularity in construction. Furthermore, the present study highlights the current differences between circular economy in theory and practice.