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Decarbonization is gaining priority from the macro to the micro level. However, achieving this is a critical challenge, as industries are still immature. This study explores the practices used to calculate and reduce embodied carbon (EC) in New Zealand (NZ) commercial construction projects. In the Paris Agreement, NZ pledged to reduce its net GHG emissions to 50 percent below the gross 2005 levels by 2030. The built environment generates approximately 40% of global greenhouse gas (GHG) emissions, with 11% being generated by manufacturing materials. EC represents carbon dioxide (CO2) emitted into the atmosphere throughout the extraction, fabrication, transportation, and assembly of building materials. A survey questionnaire was distributed to stakeholders in commercial construction via the New Zealand Institute of Quantity Surveyors (NZIQS) open forum. Twenty-seven valid responses were analyzed. The survey tested and expanded on the interview findings. Calculating and reducing EC are not mandatory in NZ. Most industry professionals had yet to experience EC calculation in projects. Clients most commonly drive EC reduction in public projects with calculations that are often conducted during the concept or detailed design stages. The challenges in measuring and lowering EC include a lack of client willingness to fund EC calculation, lack of knowledge and experience, lack of previous cost data, lack of EC materials, and lack of fit-for-purpose EC calculation tools. These findings may inform NZ government policy initiatives supporting EC reduction to meet their 2050 target. [ABSTRACT FROM AUTHOR]

Closed-loop control of commercial building heating, ventilating, and air conditioning (HVAC) for demand response requires measurements used as feedback to the controllers. Demand response effectiveness is usually measured as a power deviation from baseline, but the building automation system (BAS) does not usually collect power measurements, and whole-building electric meters typically measure power at intervals of 15 min, which may be too slow for some types of demand response. Demand response strategies are sometimes focused on components of building HVAC systems, e.g., the response of supply/return fans to temperature set-point changes, but these components are usually not submetered. Fan power can be estimated from physics-based models leveraging BAS data, e.g., airflow measurements; but our ability to effectively close the loop on these estimates is not clear. In this paper, we introduce a massive dataset that contains both submetered fan power data and BAS data for several building HVAC systems during typical operation and demand response events. Through a case study we show that models leveraging BAS data alone do not provide accurate estimates of fan power during event transients, making it unlikely that closed-loop control of commercial building HVAC components for demand response would be effective using BAS data alone. This demonstrates the value of submetering HVAC components. More broadly, our dataset will enable future research bridging the gap between building control and power systems research. [ABSTRACT FROM AUTHOR]

Decarbonization is gaining priority from the macro to the micro level. However, achieving this is a critical challenge, as industries are still immature. This study explores the practices used to calculate and reduce embodied carbon (EC) in New Zealand (NZ) commercial construction projects. In the Paris Agreement, NZ pledged to reduce its net GHG emissions to 50 percent below the gross 2005 levels by 2030. The built environment generates approximately 40% of global greenhouse gas (GHG) emissions, with 11% being generated by manufacturing materials. EC represents carbon dioxide (CO2) emitted into the atmosphere throughout the extraction, fabrication, transportation, and assembly of building materials. A survey questionnaire was distributed to stakeholders in commercial construction via the New Zealand Institute of Quantity Surveyors (NZIQS) open forum. Twenty-seven valid responses were analyzed. The survey tested and expanded on the interview findings. Calculating and reducing EC are not mandatory in NZ. Most industry professionals had yet to experience EC calculation in projects. Clients most commonly drive EC reduction in public projects with calculations that are often conducted during the concept or detailed design stages. The challenges in measuring and lowering EC include a lack of client willingness to fund EC calculation, lack of knowledge and experience, lack of previous cost data, lack of EC materials, and lack of fit-for-purpose EC calculation tools. These findings may inform NZ government policy initiatives supporting EC reduction to meet their 2050 target.

Design/Bid/Build (DBB) delivery is the traditional approach for establishing the least cost for building projects, but other alternative project delivery methods have become increasingly popular. Although multiple studies have compared delivery methods for vertical construction, there have not been any comprehensive studies quantifying how delivery methods compare specifically for repetitive commercial construction. This research utilized a mixed methods approach to compare the cost, schedule, and quality of Construction Manager/General Contractor (CM/GC) delivered projects with DBB projects for repetitive commercial construction, using 173 facilities built with the same base floorplan. A comprehensive quantitative comparison was conducted, excluding potential confounding variables and including short- and long-term direct and indirect costs, construction time, and quality assessment scores. Contractors and project managers were also surveyed regarding their perceptions of CM/GC process effectiveness in a repetitive construction environment. This research demonstrated that the CM/GC delivery method was more effective for repetitive commercial construction, uniquely quantifying the relative cost, schedule, and quality improvements of CM/GC delivery over DBB projects. Compared to DBB, CM/GC projects produced total construction cost savings of 5.4%, a 20% shorter construction cycle time, consistently higher quality assessment scores, and an overall reduction in repair costs of 34%. [ABSTRACT FROM AUTHOR]

HIGHLIGHTS* Identify patients with chronic conditions that might benefit from outreach efforts, and the place to start is with the EHR.* Start small and build gradually. Is the practice getting [...]

This article reports the findings of a quantitative study on the relationship between various project performance outcomes and the use of Building Information Modeling (BIM), within the commercial construction industry. The literature review identified inconsistent results among prior qualitative and quantitative work concerning the relationships of key project performance measures and BIM use. Data on 13 variables from 93 completed construction projects were collected and examined through a causal comparative research design. Projects that used BIM (in design or construction) were not found to experience significant performance outcomes when controlling for the contribution of other independent variables and covariates at the 95% confidence level (CL). At the lower 90% CL, however, projects using BIM in construction experienced significantly higher levels of schedule growth than projects that did not use BIM in construction. Recommendations are made for training of construction management staff as a step to avoid unwanted schedule growth associated with BIM use during construction. This study is one of a very small group of rigorous quantitative analyses of BIM project performance outcomes conducted to date; additionally, it is the only study that has analyzed BIM in a multivariate context that controlled for the contribution of other project variables not directly related to BIM use. [ABSTRACT FROM AUTHOR]