Globally, only 2% of existing building stock is built yearly; the remaining 98% already exist. Energy consumption and indoor thermal comfort of the existing building stock are not encouraging. This is due to many challenges associated with existing buildings; the challenges range from cracks, leakages, poor insulation, heat losses and high rate of unsustainable technologies. This paper investigates possible barriers facing the adoption and application of sustainable technologies (STs) for sustainable or energy-efficient upgrade of existing buildings. New STs are manufactured on a regular basis to meet improved energy efficiency standards, yet there are minimal actions/attempts to adopt and apply improved technologies in existing buildings for energy efficiency. Indeed, there are limited studies focused on the use of qualitative approaches to identify barriers to adoption and use of STs. Thus, a semi-structured interview approach was adopted and applied using sustainability/energy efficiency professionals, building services engineers, project managers, architects, and facility managers in Australia. The results indicate that barriers to the adoption and application of sustainable technologies are perceived benefits in demolish-and-build, age of building, cost of STs, perceived poor payback time, unreliable energy-savings projections, existing design, hidden and overall cost of renovation, and cost of STs.

The main purpose of the research is to investigate drivers that motivate homeowners, investors, government institutions etc., to undertake green renovation. Sustainable upgrade actions have been slow although new smart technologies such as solar panels, e-glazing, insulation systems, cogeneration etc., are developed or upgraded every year. At such a slow pace, the existing building stock presents a challenge as drivers are not rigorously identified and applied. A survey questionnaire was designed to examine all the drivers that encourage energy renovation. Extensive review of the literature provided a theoretical framework that supported the study. The survey was administered to energy consultants, architects, quantity surveyors, facility managers and engineers with sufficient professional experience. The data was analysed using means, T-test analysis and Mann–Whitney U test. The results establish a relationship between drivers and upgrade of existing buildings and systems. The findings identified a strong level of agreement among the respondents on the drivers of green renovation. Incentive and support systems, penalties for noncompliance, high energy bills, energy conservation and policy and regulations, awareness etc., are some of the motivating factors that drive energy management retrofit.

The construction industry has been seen as one of the hazardous industries. This is because the industry has a poor health and safety performance record compared to other industries all over the world. The Labour Act provides that it is the duty of an employer to ensure that every worker employed by him or her works under satisfactory, safe and healthy conditions. The objective of this study is to identify how clauses in the Labour Act 651 addressing appropriate health and safety standards are used in construction sites and identify possible challenges facing the adaptation of the requirements of Health and Safety in the Labour Act. Using convenience and snowball sampling techniques, 200 questionnaires were distributed to architects, quantity surveyors, site and structural engineers. One hundred and twenty-one were retrieved representing a response rate of 61.5%. The data was analysed using descriptive statistics, and Relative Important Index ranking. The findings indicate that clauses in the Labour Act 651 addressing appropriate health and safety standards are poorly adhered to. The findings also indicate that the key challenges facing the adaptation of the Labour Act are; inadequate training, poor risk assessment, cost, reporting shortfalls ,lack of H&S professionals, inadequate H&S policies, data collection shortfalls, lack of H&S education, communication shortfalls and workers attitudes towards Health and Safety.

Sustainable upgrades include actual case studies with before and after retrofit results, case studies with simulated results and use of computer systems to predict energy savings based on exiting building parameters. In the latter no actual renovations are done thus technologies and systems are assumed. The review used real cases including simulations and adopts a mix of systematic and content analysis approaches. Thus, over 288 articles were gathered from all the major scientific journals using Scopus, ProQuest, Web of Science etc. The sample was reduced to 230 articles based on the search themes; thereafter, a detailed focus on the methods used provided basis to trim the articles to 47. Sustainable technologies identified cover those installed to the external façade, indoor areas, air filtration, insulation systems, building elements, heating, ventilation and cooling (HVAC) systems, sensors, lighting, hot and cold water systems such as boilers, chillers, pumps, motors and renewable energy technologies. The results show sustainable technologies have been used to improve various existing buildings. Also, the results indicate high rate of adoption of insulation systems for external and internal walls, roofing and ceiling elements. This paper provides evidence to support the drive towards environmental sustainability through the adoption and installation of sustainable technologies. Policies to trigger demand and installation could further improve actions towards greenhouse gas reduction.

The negative effects of construction on the environment have been acknowledged all over the world. Materials and technologies are developed regularly to help address challenges posed by rising populations and related energy demands and emissions. The purpose of this study is to investigate decisions that influence materials selection for sustainable upgrade of existing structures and identify the extent to which environmental factors are applied. The study adopted a quantitative approach that involved an extensive literature review and a survey questionnaire randomly distributed to professionals in the construction industry as a way of identifying innovative sustainable upgrade decisions. A Mann-Whitey U test analysis was applied to establish decisions affecting materials selection. The results show materials selection decisions for sustainable upgrade of existing structures are focused on cost and physical properties including demand for materials, cost of sustainable upgrade, colour and texture of construction materials. Policy decisions and implementation strategies are required to improve environmental sustainability, and thereby reduce the negative effects of construction on the climate. Environmental considerations do not influence decisions on materials selection as much as cost, physical and aesthetics factors.