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The construction industry is the major source of Construction and Demolition (C&D) waste in Hong Kong. The capacity of landfills will reach saturation in a couple of years. Refurbishment and renovation projects contribute 10 to 20% of C&D waste. There are about 50,000 buildings in Hong Kong that are more than 30 years old and may require extensive refurbishment or renovation under the Mandatory Building Inspection Scheme. Besides, most new owners/tenants will renovate their premises before moving in. There is an urgent need to explore and develop effective waste management strategies and measures for refurbishment/renovation projects in Hong Kong. This research study aims to identify the types and estimate the quantities of refurbishment and renovation (R&R) waste; and evaluate the effectiveness of Pre-refurbishment Auditing (PRA) as a waste management strategy for these projects. Desktop study, semi-structured interviews, site observations and document reviews were used as the data collection methods to achieve the objectives of this research study. Content Analysis and Thematic Analysis were used for data analysis. The findings revealed that PRA is an effective strategy to be implemented in R&R waste management. Barriers for implementing PRA include (a) lack of sorting and storage spaces; (b) high cost; (c) insufficient government supporting policy; (d) complicated recycling processes, (e) immature recycling market, and (f) insufficient public education. To tackle these obstacles, government is recommended to take lead in conducting PRA and issue guidelines as a reference. The Building Department can also consider taking up an active role in policy making and promoting PRA.

Earthen materials have been used in civil engineering construction worldwide with different forms, such as mud, adobe, rammed earth and bricks. Compressed stabilized earth blocks (CSEB) can be considered as a new member of the earthen building material family. Also, it can overcome the problems associated with fired bricks and cement blocks. Cement is the most commonly used as stabilizers to enhance the properties of CSEB. The governing factor which controls the properties of CSEB is the amount of clay content in the soil. Researches have concluded that about 25% of clay and silt (finer) content contributes to high compressive strength. However, controlling of larger particles is not addressed much. This study focused on controlling the finer content as well as larger particles with the use of construction waste (mostly with crushed concrete) and river sand. Selected soil was modified to get the finer content as 5%, 10%, 15% and 20%. This modification was done by adding river sand and construction waste to the soil to optimize the particle packing based on particle packing theories. Cement was used as the stabilizer with 6%, 8%, and 10%. (150 × 150 × 150) mm3 cubes were cast and tested for dry density, water absorption, 28 days wet and dry compressive strength, accelerated erosion and compared with SLS 1382; part 2 requirements. Block properties were conformed with SLS 1382 requirement when finer contents are 10% and 5% with 10% and 8% cement. Further, Industrial-scale blocks of (350 × 100 × 175) mm3 made with 10% finer and 8% cement satisfied the Grade 1 block properties. CSEB made mixing with construction waste contributes to manage the environmental pollution due to construction waste while giving a fair solution to the problem with the shortage of building materials.

Waste generated by the Construction Sector represents an environmental problem in many countries. To achieve increasingly eco-efficient waste management, Life Cycle Assessment (LCA) provides an objective method for the quantification of the potential impact that waste management exerts on the environment. Traditionally, LCA has focused on the evaluation of non-prevention scenarios once the waste is generated, mainly by showing the benefits of recycling vs. disposal. Consequently, the literature has hardly addressed the positive environmental impacts caused by waste prevention, that is, the reduction at source, which constitutes the preferred option of any waste management hierarchy. Therefore, this study proposes a model to simulate the environmental performance of the prevention vs. the non-prevention of construction waste production. The model is applied to an urban system of residential buildings in Spain. The results provide evidence of the environmental benefits achieved with the prevention scenario. The prevention scenario reduces the construction waste generated in the non-prevention scenarios by up to 57%. Furthermore, it allows a potential reduction of up to 4.6 and 171.1 times the impact caused by the disposal scenario; and up to 1.7 and 8.3 times those of the recycling scenario. The model can be implemented in other contexts with other reference buildings, and enables the environmental benefits of reduction strategies to be studied, thereby providing a tool to guide and support decision-making during the building design stage. Moreover, the results obtained can help professionals and policymakers to incorporate effective construction waste prevention measures in waste prevention plans and programs. Spanish Government Spanish Government ref. BIA2017-84830-R

The modern world is facing unprecedented population growth and increasing demand for consumer goods which, in turn, causes a demand for an increasing supply of materials. At the same time, technological advancement has enabled the development of novel materials suitable for a wide range of applications. Composites are a great example of such materials because they can be produced from feedstock which is not suitable for other applications, such as waste. A substantial body of research has been conducted exploring various industrial and municipal waste streams. Composite matrices can be made of low-quality recycled plastic originating from construction and demolition activities while fillers can be made from a variety of waste streams, such as primary sludge, wood waste, sawdust, agricultural residues, mineral wool, and plasterboard, among others. Generally, the cumulative share of the matrix and filler is above 90% of the composites, thus significantly contributing to a potential reduction in environmental impacts, including climate change. The climate change impacts of waste-derived composites (WDC) can be best assessed using the carbon footprint (CF) methodology. The CF is a specific node of life cycle assessment (LCA) focusing on climate change impacts. The method accounts for the emissions and removal of greenhouse gases during all life-cycle stages of composites or parts thereof. Post-print / Final draft

Material use in buildings affects the climate over centuries, however, temporal aspects are often ignored in Life Cycle Assessment (LCA). Results too often promise uncontested precision of impacts occurring far into the future. Additionally, the validity of building LCAs is being questioned over inadequate scope and inventory. A dynamic LCA method for material use in buildings that addresses those concerns is presented, along with a case study of 20 buildings. In particular, a novel solution to account for delayed emissions is presented, along with future technological improvements. Climate change effects of material use in construction, operation, and end-of-life phases are estimated, from production, transport, construction-waste incineration, biogenic carbon-sequestration, and cement carbonation. Building subpart metrics reveal drivers of impacts and are used for generating statistical emission profiles. Application on a bottom-up harmonized dataset produces statistical results for building types (typology, timber/concrete) and building subparts (building elements, material categories). Global warming policy targets requires that the building industry focuses on interventions with short-term effects, such as low-impact materials in the construction phase and reduced construction waste. Uncertainty is estimated, and parameter influence assessed with global sensitivity analysis. Time horizon (TH), building lifetime, and construction waste parameters are found most sensitive. The method reduces uncertainty of postulated future impacts; an important step in the direction of policy-relevant modeling. We recommend that building LCA modeling practice adopts the presented methodological concepts to gain trust and policy-relevance. © 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

The 2015 Mw 7.8 Gorkha Nepal Earthquake had severely damaged buildings producing massive amount of debris. This paper assessed the amount of debris generated and construction waste during post-earthquake housing reconstruction in the earthquake most affected two districts. The study was carried out between April 2017 to December 2019, in Gorkha and Sindhupalchok districts of Nepal. The questionnaire survey were conducted in 17,814 households (Gorkha: 4896 and Sindhupalchok: 12,918) that were reconstructed after the earthquake. The sample household was selected randomly and the amount of debris and waste generated from each household was visually estimated. A z-test was performed to determine the quantity of debris and waste generated in each household at district as well as local administrative level. The result showed significant difference between the total amounts of debris generated in two districts - Gorkha (m = 17.03 m3/HHs; SD = ± 10.15) and Sindhupalchok (m = 21.61 m3/HHs; SD ± 8.92). Construction waste that was produced in construction sites in Gorkha and Sindhupalchok were 1.11 m3/HHs and 1.59 m3/HHs respectively. Proper management of debris and waste was lacking due to the absence of policies and guidelines on debris and waste in Nepal. However, individuals reused 57.96% of generated debris for housing reconstruction. The study recommends for preparation of debris and waste management plan for the future reconstruction activities.

Many rehabilitation operations of historic buildings have not succeeded to utilize appropriate material for purpose of the project. Currently, the use of construction waste, especially the waste brick, is largely expanded in the world due to construction and rehabilitation of buildings. For efficient and sustainable use of such material in the rehabilitation of the architectural ornaments, an experimental study was conducted to examine the influence of the waste brick content on the physical and mechanical properties of the gypsum mortar. The materials used to prepare the gypsum mortar were gypsum, natural sand, waste brick, water and superplasticizer. The main variable in this study were the waste brick content (0% to 100%) and the type of the substrate (limestone and brick). The W/B ratio of all the mixtures was kept constant to maintain a similar level of the workability. Several tests were performed to assess the physical and the mechanical behaviour of the gypsum mortars including the adhesion test, XRD and the SEM analysis. The results found show that the adhesion strengths in the mortars are more important when the substrate is made from limestone with the regard to the substrate made with brick. However, excessive percentage of waste brick in the mortar can lead to adverse effects and reduce the adhesive strength. Gypsum mortars made with 75% of waste brick should be recommended for the rehabilitation of the architectural ornaments., (undefined)

Existing energy infrastructure have a technical and/or economic lifecycle predetermined by the lifetime of certain components. In energy infrastructure, the residual lifetime of civil structure or other components with a longer life is usually wasted. Modular energy infrastructure can be reconfigurable decoupling the life of the infrastructure from their modules, and extending module and/or infrastructure lifecycle. Modularisation could become a cornerstone to enable circular economy (CE) and enhanced sustainability. Remarkably, despite the growing interest among policymakers, practitioners and academics in both CE and modularisation, there is a lack of knowledge about the link between CE and modularisation in energy infrastructure. Through a Systematic Literature Review, this paper derives the gap in knowledge regarding the link between CE and modularisation in energy infrastructure. This link is then investigated in other sectors identifying relevant implications such as reduction of construction waste and achievement of the closed-loop material cycle. Furthermore, the case of Yamal Liquefied Natural Gas project is used to compare and contrast two perspectives: “Traditional modularisation” and “Modular CE”. Lastly, the paper discusses existing policies, provides policy recommendations to foster “Modular CE” in energy infrastructure and suggests a research agenda.

Solid construction waste from the demolition of old buildings has reached millions of tons worldwide. Recycled aggregates are obtained by crushing and sorting waste concrete blocks in construction waste. Concrete prepared by replacing some or all of natural aggregate with recycled aggregate is called recycled concrete. The engineering application and scientific issues of recycled concrete are related to the importance and effective promotion of construction waste recycling. This chapter describes the use of construction waste recycling, recycled coarse aggregates, to prepare recycled concrete as a potential alternative to natural aggregate concrete, which discusses the mechanical properties, durability, and other applications of recycled concrete. In particular, for a layer of old mortar that is not easily peeled from the surface of recycled coarse aggregate, one of its feasible uses is as a self-repairing concrete for microorganisms. The old mortar on the surface of recycled aggregate can improve the repairing effect and provide a good repairing environment as a microbial self-repairing carrier due to its inherently weak alkaline porous property. On the other hand, recycled coarse aggregates containing natural stone have better strength than other self-repairing carriers, and can serve as a carrier to significantly improve the performance of recycled concrete without adversely affecting the environment.

Cement manufacture is responsible for 5-7% of world CO2emissions. Cement is primarily used in concrete, the most used material on the planet and a critical part of any analysis of emissions reduction strategy. To estimate the potential for reducing demand, this work analyses material flow in the cement industry, using the UK in 2014 as a case study. Combining published data, analytic assumptions, and interviews we estimated the material flow of cement from the production to a breakdown of its use in applications. Having broken down the demand for cement into 25 applications, multiple material efficiency techniques were considered: substituting cement for calcined clay and limestone, reducing the cement content of concrete, post-tensioning floor slabs, using more precast building elements, reducing construction waste, and reducing the overdesign in construction. We produce a final estimate of the total reduction in emissions achievable from material efficiency: 51.3%. Due to overlap and interactions between the methods, the attribution of the carbon abatement depends on the sequence of application. In this analysis, we have applied the reduction of overdesign last, because it is independent of the others, and would require a cultural change. We show then that cement demand from floors, repairs and maintenance, concrete beams, and applications within the transport sector should be targeted. The substitution of cement with calcined clay and limestone has the biggest potential to reduce cement demand (27%) and carbon emissions in the UK. Reducing the amount of cement in concrete has the next highest potential (10%), followed by post-tensioning floor slabs (3%)., NMZL/112 RG82144 EPSRC ref EP/N02351X/1

Beginning with an overview of the current waste landscape, including green engineering, processing principles and regulations, the book then outlines waste streams and treatment methods for over 25 different types of waste and reviews best ...

Recent influential reports like the World Economic Forum’s “Global Risks 2017” have identified the failure of climate-change mitigation and adaptation to be among the greatest risks to humanity in the foreseeable future. The construction industry is at the center of this debate. Greenhouse gas emissions from the building sector have more than doubled since 1970 and the industry currently consumes nearly one-third of global energy consumption, making it responsible for about one-third of total direct and indirect energy-related carbon dioxide CO2 emissions. Energy demand in buildings is also predicted to rise by almost 50% between 2010 and 2050 and a 25% reduction in total energy use would represent energy savings of more than 40 exajoules (EJ), equivalent to total annual current energy use in India and Russia combined. Historically, the construction industry has also contributed hugely to environmental pollution, waste, and degradation. For example, in the United Kingdom, construction waste consumes more than 50% of overall landfill volume with 70 million tons of construction waste being discarded annually. Similarly, the US construction industry generates over 100 million tons of construction waste per annum and contributes approximately 29% of the solid waste going to landfill. In Australia, construction activities generate 20%–30% of all the waste entering landfills and in Hong Kong the figure is around 25% which amounts to about 3850 tons per day of construction waste. The construction industry is also a huge consumer of natural resources with approximately 3 billion tons of natural raw materials (40%–50% of the total flow in the global economy) being used each year in the manufacturing of building products and components worldwide. Buildings in use have also been estimated to be responsible for 12% of global water use.

Notwithstanding that efforts made at the design stage of building construction projects have significant impacts on project outcome, most waste management efforts are usually focussed on construction stage. This is albeit the understanding that construction waste could be significantly reduced through design activities. This study investigates the underlying design measures that are capable of minimising waste generated by construction and demolition activities. Using exploratory sequential mixed method research, the study employs focus group discussions and thematic analysis at the exploratory phase, while questionnaire and structural equation modelling were used at the explanatory stage of the study. The study suggests that construction waste could be significantly reduced by designing for standard materials size and by designing for modern method of construction, thereby minimising waste due to breakage, materials leftover and other major causes of waste. The study further suggests that the design process and design documentation are key underlying measures for mitigating waste in construction projects. This could be enhanced through such critical success factors as a collaborative delivery process, which is characterised by early involvement of contractors and adequate coordination of design between various disciplines involved. Findings of this study would assist designers and other construction stakeholders in understanding the significant measures for designing out waste in construction projects.

The formation of technogenic deposits (TDs) in urban areas resulted from the improper disposal of household, industrial, and civil construction waste. The present study focuses on identifying the types of pollutants in TDs and the dangerousness/toxicity to the pedological layer in the city of Araguaina, located in the northern region of Brazil. The methodology was based on TD location by satellite images; structural and textural characterization of technogenic materials; identification of types of polluting elements; and their danger ratings and toxicity according to the norms and parameters of the ABNT/10004 (Brazilian Association of Technical Standards). Technogenic deposits are mainly composed of inert materials, such as concrete (CaMg) and Ca(SO4), bricks and tiles (clay), ceramics and metal structures, together with the presence of metallic minerals, such as Fe, Al, and Zn, plastics (PVC, PET, and PS), and paint, including Pb, Cr, Zn, Ti, among others. Due to the hazardousness and toxicity of these elements, especially the heavy metals resulting from paints, it is necessary to remove the contaminated material to landfills and to decontaminate the soil through the use of appropriate techniques.

Enormous resources are invested in Europe for the transition into a sustainable, low carbon, and resilient society. In the construction sector, these concepts are slowly being applied to the renovation of the existing building stock by enforcing their deep and holistic renovation targeting sustainability, safety and resilience. Effectiveness of such an approach to the renovation with respect to traditional retrofit actions emerges when broadening the time frame of the analyses, shifting from the construction time to a life cycle perspective. In this case, the potential of the holistic approach becomes clear in reducing costs, impacts on the inhabitants and impacts on the environment over the building life cycle. Within such a new perspective, new technology options are needed to innovatively combine structural retrofit, architectural restyling and energy efficiency measures. Furthermore, a new design approach conjugating the principles of sustainability, safety and resilience over the building life cycle is required. In such a transition, synergistic and cooperative work of researchers, design professionals, and all the stakeholders in the construction sector is required. In this paper, the basic features of an expanded Life Cycle Thinking (eLCT) approach will be presented, which not only entails the use of recyclable/reusable materials, but also encourages interventions carried out from the outside the buildings to reduce building downtime and avoid inhabitant relocation. In addition, such an expanded LCT fosters the adoption of reparable, easy maintainable, adaptable and fully demountable solutions, such as those featuring dry, demountable and pre-fabricated components. Finally, it addresses the need to account for the End of Life scenario from the initial design stages to guarantee selective dismantling and reuse or recycle to reduce construction waste. Finally, a discussion on the main barriers and challenges in the transition towards this new approach to the renovation of existing building stock is briefly presented.

Legislation and fiscal policies have remained the key drivers of construction waste minimization. It has often been suggested that reducing waste to the landfill does not only require improvement on existing waste management policies and fiscal framework; there is a need for adequate inputs from the construction professionals. As a means of engendering effective waste management policies, this study explores industry practitioners’ viewpoints on effective policies for minimising waste landfilled by the UK construction industry. Using exploratory sequential mixed method approach, qualitative and quantitative methods were used. In the first phase of the study, data was collected through focus group discussions with 24 experts from the UK construction industry. Findings from the qualitative study served as an input into a questionnaire, which was used to elicit a wider opinion from 63 experts at the quantitative stage of the study. The study suggests that for waste management legislation and policies to effectively drive construction waste minimization, six key measures are important. These include (i) provision of tax breaks and incentives to good waste performers and waste management businesses; (ii) increased targeting of design stages in policies; (iii) Extension of sustainable design appraisal systems by allocating more points to proven waste performance measures; (iv) increased stringency of legislative measures by requiring use of proven waste efficient design, procurement and construction methods; (v) increased stringency of fiscal policies by increasing penalties for poor waste performance; and (vi) corroboration of policy requirements with enablers and facilitators. The strategies through which each of the legislative and fiscal measures could be tailored and enhanced are discussed in the paper. By embracing both stringent and palliative policy measures suggested in the study, substantial construction waste could be diverted from landfill.

© 2016 Elsevier Ltd. As a result of increasing recognition of effective site management as the strategic approach for achieving the required performance in construction projects, this study seeks to identify the key site management practices that are requisite for construction waste minimization. A mixed methods approach, involving field study and survey research were used as means of data collection. After confirmation of construct validity and reliability of scale, data analysis was carried out through a combination of Kruskal-Wallis test, descriptive statistics and exploratory factor analysis. The study suggests that site management functions could significantly reduce waste generation through strict adherence to project drawings, and by ensuring fewer or no design changes during construction process. Provision of waste skips for specific materials and maximisation of on-site reuse of materials are also found to be among the key factors for engendering waste minimization. The result of factor analysis suggests four factors underlying on-site waste management practices with 96.093% of total variance. These measures include contractual provisions for waste minimization, waste segregation, maximisation of materials reuse and effective logistic management. Strategies through which each of the underlying measures could be achieved are further discussed in the paper. Findings of this study would assist construction site managers and other site operatives in reducing waste generated by construction activities.

This chapter explores the definition of a green material and natural versus synthetic materials. It also discusses low-emitting materials such as adhesives and sealants, the harmful effects of toxins, and the potential impact that building materials have on the environment. Characteristics of various flooring systems such as carpet, PVC/vinyl, cork, bamboo, earthen, building materials, and tile are explored. Building elements such as windows, gypsum wall board (drywall), siding, roofing (including green roofs), and wood products (e.g., MDF) are investigated. The reader is then introduced to advanced framing techniques, structural insulated panels (SIPs), insulated concrete forms (ICFs), and concrete applications. A number of green strategies are outlined (facilitates achieving LEED® credits) such as material reuse, construction waste management (to minimize materials going to landfills), material recycling, regional materials, rapidly renewable materials (bamboo, cork, insulation, linoleum, straw bales, wheatboard, wool, etc.), and straw-bale construction. In addition, the importance of using green office equipment that is ENERGY STAR® certified is emphasized. The purpose of forest certification and certified wood is explained as is life cycle assessment (LCA, also known as life-cycle analysis) of building materials and products.

Different types of industrial construction and demolition wastes in various places were collected. The mercury content varies much overall, whereas the wastes from the chemical industry contain most due to the mercury-containing raw materials used. Waste from the light industry poses a high risk of Cd. Residential wastes and recycled aggregates exhibit a low ecological risk. The mobility fractions of heavy metals can be very high; most anthropogenic polluted metals bind loosely with minerals in construction waste. The metals easiest to be leached are Zn and Cu, whereas Cd is the hardest. A high Cd content exists in pesticide manufacturing factory, mainly coming from phosphorus rocks. These wastes are also severely contaminated by organophosphorus, intermediates, and pyrethroid pesticide. Pesticides spread all over the plant both in enclosed workshops and in residues, in which bricks and coatings contain the most. Centralized collection for disposal of wastes can only eliminate part of the contaminated waste. Risk assessment indicates that highly noncarcinogenic risks exist, especially in dermal contact and oral ingestion. Industrial construction and demolition waste generated in a fire/explosion accident may be hazardous and cause spread of pollution with explosion shock waves.

The UK Government has set out ambitious plans for all new domestic and commercial buildings to be zero carbon rated by 2016 and 2020 respectively. These are some of the most progressive environmental targets for the built environment in the western world. However, there are also other sustainability issues that need to be addressed by the UK construction industry, particularly negative impacts from the generation of waste. Currently, 100 million tonnes of construction waste, including 13 million tonnes of unused materials, is generated each year, with only 20% currently capable of being recycled. The majority of this waste ends up in landfill, contributing to further pollution of the biosphere. The literature suggests that these negative impacts result from a variety of causes, including ineffective leadership, ingrained cultures, outdated technologies and poor logistics. There are a number of innovative projects within the UK, particularly at a local level, that pose the question as to whether bottom up approaches may be more successful than top down policies, as set by national and local government. This paper presents a case study demonstrating the former approach within the construction industry. Research and consultancy has been undertaken collaboratively between industry, academia and professional practice in the production of 15 individually designed sustainable dwellings in the North East of England. This project has employed Building Information Modelling (BIM) as a new collaborative working platform, aligned to the Modern Method of Construction (MMC). By situating this inquiry within an authentic case study it has highlighted ineffective strategies, policies and leadership, which have prevented full exploitation of the potential of BIM and MMC towards sustainable production. This inquiry supports the integration of the Framework for Sustainable Strategic Development (FSSD) into construction procurement, as a method for implementing bottom up leadership in a value driven project.

This paper addresses the efficiently reuse of the recycled construction waste cementitious materials (RCWCM). The RCWCM is firstly collected, and then subjected to crushing, grinding and thermal treatments, respectively. After that, the obtained powder material is named dehydrated cement paste (DCP) in this study. Due to the fact that the DCP has relatively high pH value and high activity, two specific attempts are tried to efficiently reuse the obtained DCP. The results show that it is possible to produce a prefabricated building material with an industry by-product (fly ash) and a recycled waste material (DCP). The compressive strength of the produced prefabricated building material can be higher than 60 MPa. Additionally, after being further dispersed, the DCP could be utilized as a high performance cement additive, which can significantly promote the hydration and microstructure development of cement.

© 2015 Elsevier Ltd. All rights reserved.Owing to its contribution of largest portion of landfill wastes and consumption of about half of mineral resources excavated from nature, construction industry has been pressed to improve its sustainability. Despite an adoption of several waste management strategies, and introduction of various legislative measures, reducing waste generated by the industry remains challenging. In order to understand cultural factors contributing to waste intensiveness of the industry, as well as those preventing effectiveness of existing waste management strategies, this study examines cultural profile of construction industry. Drawing on four focus group discussions with industry experts, the study employs phenomenological approach to explore waste inducing cultural factors. Combining findings from phenomenological research with extant literatures, the study suggests that in order to reduce waste intensiveness of the construction industry, five waste inducing cultural factors need to be changed. These include (i) "make-do" understanding that usually result in "make-do waste" (ii) non-collaborative culture, which results in reworks and other forms of wasteful activities (iii) blame culture, which encourages shifting of waste preventive responsibilities between designers and contractors, (iv) culture of waste behaviour, which encourages belief in waste inevitability, and (v) conservatism, which hinders diffusion of innovation across the industry. Changing these sets of cultural and behavioural activities is not only important for engendering waste management practices; they are requisite for effectiveness of existing strategies. Improvement in the identified areas is also required for overall improvement and general resource efficiency of the construction industry. Thus, this paper advocates cultural shift as a means of reducing waste landfilled by the construction industry, thereby enhancing sustainability and profitability of the industry.

Reduction in construction waste is a pressing need in many countries. The design of building elements is considered a pivotal process to achieve waste reduction at source, which enables an informed prediction of their wastage reduction levels. However the lack of quantitative methods linking design strategies to waste reduction hinders designing out waste practice in building projects. Therefore, this paper addresses this knowledge gap through the design and validation of a Building Design Waste Reduction Strategies (Waste ReSt) model that aims to investigate the relationships between design variables and their impact on onsite waste reduction. The Waste ReSt model was validated in a real-world case study involving 20 residential buildings in Spain. The validation process comprises three stages. Firstly, design waste causes were analyzed. Secondly, design strategies were applied leading to several alternative low waste building elements. Finally, their potential source reduction levels were quantified and discussed within the context of the literature. The Waste ReSt model could serve as an instrumental tool to simulate designing out strategies in building projects. The knowledge provided by the model could help project stakeholders to better understand the correlation between the design process and waste sources and subsequently implement design practices for low-waste buildings.

Microbial biotechnological products are developing to make new ecologically friendly and economically efficient construction materials. Low-cost, sustainable, and environmentally friendly microbial cements, grouts, biopolymers, and bioplastics are useful in civil engineering. The biobased or bio-inspired materials and processes can be used for dust immobilization in construction zones, formation of soil crust to reduce its erosion, soil biogrouting, and bioclogging in the construction of levies or tunnels, biocementation of the porous soil for strengthening, biodesaturation of water-saturated soil biocoating and biorepair of the concrete surfaces, construction of artificial coral reefs, decoration of the building exterior, for the improvement of cementitious materials and production of biodegradable plastic composites reducing the area of construction waste landfills.

This chapter contains information about the main issues in the estimation of construction waste (CW), for the purpose of promoting waste recovery within the framework of sustainable construction. Several studies and quantisation tables estimating construction and demolition (C&D) waste, both regionally and on a smaller scale and in different types of buildings, are given. The difficulties and importance of obtaining a greater knowledge of CW from the initial conception of the project are discussed. Seventeen examples and case improvement achieved in the management scenarios and the benefits of implementation in attaining sustainable buildings.

Publisher Summary The built environment consumes more natural resources than necessary and therefore generates a large amount of waste. This chapter sheds light on the idea of rethinking construction waste management by reengineering processes and practices to reduce construction waste at source. It examines the concept of waste and definitions. Rethinking waste management in construction requires adopting ‘cyclic’ rather than ‘linear’ approach to design and construction. This requires re-engineering current practice to contribute to a cleaner environment through efficient and cost effective sustainable waste minimization strategies. Following this, the chapter discusses construction waste quantification and source evaluation. It also explores current thinking on construction waste research and appraises the current construction waste management and minimization status in the United Kingdom (UK) in terms of drivers and pressures for change, design and onsite practices, and challenges and enablers. For waste minimization to be effective and self-sustaining, it is important that all stakeholders along the construction supply chain embrace a more proactive approach in dealing with waste. In recognition of the responsibility of the architectural profession, through its leading role in project management and a key player in the construction industry, architects should move beyond the concept of eco-efficiency through bolt-on environmental strategies and strive to adopt eco-effective practices by implementing a holistic approach to design out waste, which will be reinforced in tender documents and implemented during the construction stage, in addition to the capture and dissemination of lessons learnt to inform construction waste reduction baselines and benchmarking in future projects.

The new EU challenge is to recover 70% by weight of C&D waste in 2020. Literature reveals that one major barrier is the lack of data. Therefore, this paper presents a model which allows technicians to estimate C&D waste during the design stage in order to promote prevention and recovery. The types and quantities of CW are estimated and managed according to EU guidelines, by building elements and specifically for each project. The model would allow detection of the source of the waste and to adopt other alternative procedures which delete hazardous waste and reduce CW. Likewise, it develops a systematic structure of the construction process, a waste classification system and some analytical expressions which are based on factors. These factors depend on technology and represent a standard on site. It would allow to develop a database of waste anywhere. A Spanish case study is covered. Factors were obtained by studying over 20 dwellings. The source and types of packaging waste, remains, soil and hazardous waste were estimated in detail and were compared with other studies. Results reveal that the model can be implemented in projects and the chances of reducing and recovery C&D waste could be increased, well above the EU challenge. Consejería de Vivienda y Ordenación del Territorio de la Junta de Andalucía

Publisher Summary Construction and demolition (C&D) wastes are considered the major wastes that are produced by the construction and demolition industries. Construction and demolition waste may include packaging material and land-clearing debris. As a result of disposing of such wastes, there is a minute impact to the environment. First, it is unsightly and can lead to huge economic losses and the second impact is on the groundwater quality. This chapter discusses the sustainability of construction and demolition waste and explains the relevant guidelines to owners and contractors. This includes three case studies. The first case study uses the 7Rs rule as a guideline for handling construction waste in a manner that applies “cradle-to-cradle” concepts. The second case study demonstrates the amount of money that is typically spent on getting rid of construction waste. The third and final case study demonstrates the advantages and benefits of implementing “cradle-to-cradle” concepts on construction waste.

Publisher Summary Most of the construction trades in Hong Kong have their strict and hard boundaries, which workers will not or cannot cross over and hence induces inflexibility both for workers in seeking continuous employment and for employees in labor deployment. This results in the lack of continuous employment for workers due to the daily pay arrangement of the workforce. The use of prefabrication has been strongly advocated recently in the industry, as it can help to improve site safety by providing a cleaner and tidier site environment, enhance quality by producing elements under the factory conditions, and eliminate site malpractices. Further, factory production can reduce wastage and encourage re-cycling of construction waste, leading to environment protection and sustainability of the industry. The Hong Kong Special Administration Region (HKSAR) government can encourage contractors to set up prefabrication yards within the Hong Kong region by offering land with low rental fees. To facilitate building control and to ensure that the use of materials and construction methods coupled with the performance of the finished products do comply with the Hong Kong Building Regulations, the large developers, especially the public clients, can mandate that all prefabrication yards must be located within the Hong Kong SAR or located in a place acceptable to them.

Publisher Summary Gelation of construction waste mud using water-soluble polymers or superabsorbent polymers (SAPs) improves handling of mud by creating a more manageable soil-like appearance. Compared to the traditional mechanical dehydration, this is a much simpler process. However, under the current legal system, even if treatment is given, if the treated material is not value-added, it still must be discarded as industrial waste. Thus, it remains similar to the dehydration approach. The chapter discusses the treatment and dumping of construction waste mud. Generated waste mud is often treated at either the construction site or the intermediate treatment plant, followed by disposal at the final treatment plant. The main intermediate treatment methods are machine treatment and chemical treatment. Treatment of waste mud by chemicals has been used for many years. The chemicals used are inorganic ones—such as cement and calcium carbonate—and organic ones—such as water-soluble polymers and SAPs. These are widely used methods as they are quite simple. The chapter presents the current situation regarding use of these compounds. Depending on the development of technology as well as regulations, more innovative and focused technological progress may follow.

The continuous growth of municipal solid waste generation, especially from construction activities, has been responsible for the appearance of many and efficient municipal solid waste management policies from public authorities. An efficient waste management program can avoid inappropriate waste, disposal, which can cause damage to both environmental and public health. Additionally, it may even lead to the development of recycling programmes. Giving special attention to solid waste from civil construction enterprises, it is important to develop environmentally active practices among construction companies with a view to reduce waste generation, increase reuse and recycling. In order to develop alternatives for construction wastes recycling, it is important to provide efficient solid waste characterization studies. An experimental study has been carried out in the city of Salvador, Brazil. Currently, 1450 tons daily of construction and demolition (C&D) wastes has been generated in Salvador. Solid waste has variable physical characteristics that depend on the construction sector involved, the techniques employed, the construction phase and the social-economic characteristics present in the urban area in question. This paper presents the results of an intensive study of construction and demolition wastes from Salvador with the intention of creating alternative methods of increasing environmental protection and generation of low price raw material by recycling solid waste. The principal procedure used involves the characterisation of solid waste according to its physical characteristics and social-economic aspects. The results of this characterisation identified priority research lines that will help to maximise recycling of C&D waste produced in Salvador and help develop a local construction material market.

Based on experiences gained from the Great Belt Link and Oresund Link projects together with the work in the RILEM Technical Committees 34 and 121 on Demolition and Recycling of Concrete and Masonry, it is stated that much of the demolition and construction waste material generated in large construction projects can be reused. Construction and demolition waste management and handling is an important part of environmental management according to BS 7750. Recycled building rubble could substitute natural resources.

Summary Although Britain is relatively rich in natural aggregate reserves, planning approvals to develop new quarries are running at about half the rate of aggregate extraction. This paper reports on a property study of crushed concrete and demolition debris with a view to using these materials in construction instead of natural aggregate. One of the objects of the research, on which this paper reports, was to accumulate data which would be a basis for the production of a British Standard for recycled materials in construction.