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Modular construction has become exceedingly relevant against the current scenario of increasing housing demand and can respond to this need in Canada due to its advantages of rapid construction. However, a holistic environmental sustainability framework for this construction method is still lacking. This paper proposes a hierarchical-based framework to benchmark the environmental performance of modular buildings versus conventional buildings. The framework identifies criteria and indicators affecting environmental sustainability, makes composite indicators, and establishes performance benchmarks. Based on expert survey, six criteria (construction waste management, energy performance and efficiency strategies, site disruption and appropriate strategies, renewable and environmentally preferable products, regional materials, and renewable energy use) are first identified. The related indicators and sub-indicators are combined to develop indices using Technique for Order of Preference by Similarity to Ideal Solution. Robust benchmark scales were established through application of Monte Carlo analysis on data collected through experts. Finally, the developed indices were compared against the benchmark scales at different assessment levels. The proposed framework was examined for two single-family modular buildings in British Columbia, Canada. The overall environmental performance benchmarking informs the policy makers on the usefulness of modular buildings, while the criteria-level indices direct the construction industry practitioners to improve the low performing indicators. The proposed framework will enhance the sustainability of modular and offsite construction in Canada. [ABSTRACT FROM AUTHOR]

Financial Incentives (FIs) for green buildings are a major component of energy policy planning and play a vital role in the promotion of sustainable development and carbon mitigation strategies. Despite the presence of numerous FIs in Canada, there is still a lack of understanding on their distribution and effectiveness. This review first investigates the FIs available for residential and commercial buildings in Canada, and then performs a comprehensive review of studies related to FIs' effectiveness evaluation. It is found that FIs for buildings in Canada can be distributed into four categories: tax, loans, grants, and rebates. Among these, rebates from utility providers are the most common and are administered in all provinces. In addition to these, special incentives are available for three end-users (low-income, aboriginal people, landlords and tenants) and for three types of buildings (heritage, non-profit and energy rated). A clear contrast is observed on FIs offered in three regulatory regimes (Federal, provincial and municipal). Four provinces (Alberta, British Columbia, Ontario and Quebec) are leading in green building efforts. The in-depth literature review was also used to develop an understanding on the criteria used in effectiveness evaluation and the factors impacting effectiveness. Based on the findings of different studies on FIs effectiveness, a generic approach for evaluation of FIs is proposed that can help in deploying successful FIs programs. The results of this review are of importance to the policymakers, government authorities, and utilities engaged in designing and improving FIs for energy efficient buildings. • Reviews financial incentives (FIs) present for green buildings in Canada. • Determines Canadas' FIs vary with respect to number, type, and location. • Identifies factors impacting effectiveness of FIs. • Finds predominant criteria in FIs effectiveness evaluation studies. • Provides approach for evaluation of effectiveness of FIs. [ABSTRACT FROM AUTHOR]

Occupant behavior in residential buildings has a direct impact on the effectiveness of energy-saving measures. In order to realize a buildings' carbon mitigation targets, the impact of individual occupancy profiles needs to be integrated with building simulation models. This paper introduces a decision support framework as a potential solution to make energy performance upgrade choices based on different occupancy profiles. This framework has been demonstrated through a case study of two single-family detached homes in Canada, which were highly instrumented with sensors for monitoring energy input and output. The case studies represented two common occupancy profiles-(1) a family of four (consisting of 2 working adults and 2 teenagers); and (2) a retired couple. Firstly, calibrated energy models were developed by using one-year energy use data collected through an intrusive load monitoring technique. Secondly, energy upgrade combinations were considered for each profile and tested for additional investment, payback period and greenhouse gas (GHG) emissions. Lastly, the most suitable combination of energy upgrade for each profile was ranked using a multi-criteria decision-making method (e.g., TOPSIS). Results indicated that the retired couple used more energy than the family of four and required energy upgrades with usually higher payback periods to achieve the same level of GHG emission reduction. The results of this research are timely for energy policymaking and developing best management practices, which need to be implemented along with the deployment of more stringent building standards and codes. • A scenario-based framework was developed for residential homes energy upgrades. • It considers occupant behavior and preference in selecting energy upgrades. • Field data is used to represent energy use of a family of four and a stay-at-home retired couple. • Energy upgrades are same under pro-economic choices for two profiles. • Energy upgrades vary under pro-environmental scenarios for two profiles. [ABSTRACT FROM AUTHOR]

A human health risk-based life cycle assessment (LCA) framework was developed for selecting low-impact water treatment systems with a focus on heavy metal(loids) removal. The framework comprises three phases, including pilot-scale water treatment, human health risk assessment (HRA), and LCA. The application of the framework was demonstrated by a case study. Two water treatment systems employing ozonation-greensand-ferric hydroxide-based sorbent (OGF) and Birm-ferric hydroxide-based sorbent (BF) processes were used to reduce arsenic and manganese concentrations in the source water of a small municipality in southwestern Canada. The heavy metal(loids) concentration as well as material and energy use data of the two systems were collected to perform HRA and LCA. The results showed that both systems can reduce arsenic and manganese concentrations; however, the removal efficiencies of OGF and BF processes decreased with the increase of treatment volume. At a constant inflow rate, the ferric hydroxide-based sorbent needed to be replaced every 31 and 25 days in the OGF and BF processes, respectively, to ensure that arsenic concentration in the effluent would not pose any significant human health risk. The LCA results indicated that the system using the OGF process generated lower life cycle environmental impacts than the system using the BF process throughout ten years' operation. It was also found that the arsenic removal process was the largest impact contributor in both systems. The manufacturing of ferric hydroxide-based sorbent and disposal of arsenic-contaminated treatment waste accounted for the highest impact in water treatment. Image 1 • A health risk-based LCA framework is proposed for assessing water treatment systems. • Two water treatment systems designed for arsenic and manganese removal are assessed. • Human health risk assessment determines acceptable adsorbent replacement frequency. • System using ozonation-greensand-ferric oxyhydroxide treatment shows lower impacts. • Arsenic removal process generates the highest life cycle environmental impacts. [ABSTRACT FROM AUTHOR]