The Reporting of End of Life and Module D Data and Scenarios in EPD for Building level Life Cycle Assessment

This paper identifies the need for Environmental Product Declarations (EPD) to provide End of Life (EoL) and Module D data for products for use in building level Life Cycle Assessment (LCA). Although the provision of data for EN 15804 Modules A4-D is not currently mandatory for EPD, many currently report some or all of these. This paper provides an overview of the existing reporting of the end of life (Modules C1-4) and Module D and the types of scenarios used in European EPD. Using examples from existing EPD for two product groups, this paper examines the variation in approaches to scenarios for Module C and D. It explores the difficulties brought by this variation and discusses benefits from using default national scenarios at end of life, but additionally considers the advantages of providing alternative EoL scenarios for products to promote the circular economy

Design strategies for low embodied energy and greenhouse gases in buildings: analyses of the IEA Annex 57 case studies

This paper introduces the IEA Annex 57 case study method, consisting of a format for describing individual case studies and an evaluation matrix covering all case studies. Sample case studies are used to illustrate the method and the evaluation matrix through a first preliminary analysis. In compiling and evaluation existing, transparent case studies we have taken a stakeholder perspective. By so doing it is intended to identify fordecision makers the key issues affecting EE/EC in buildings. Analysis in this paper focuses on one of the six case study themes, building design strategies for EE/EC mitigation and references cases covering e.g. material selection, building shape, construction stage strategies and strategies to handle the trade-off between embodied and operational impacts in net-zero emission building design

Alzheimer's Disease Amyloid-β Links Lens and Brain Pathology in Down Syndrome

Down syndrome (DS, trisomy 21) is the most common chromosomal disorder and the leading genetic cause of intellectual disability in humans. In DS, triplication of chromosome 21 invariably includes the APP gene (21q21) encoding the Alzheimer's disease (AD) amyloid precursor protein (APP). Triplication of the APP gene accelerates APP expression leading to cerebral accumulation of APP-derived amyloid-β peptides (Aβ), early-onset AD neuropathology, and age-dependent cognitive sequelae. The DS phenotype complex also includes distinctive early-onset cerulean cataracts of unknown etiology. Previously, we reported increased Aβ accumulation, co-localizing amyloid pathology, and disease-linked supranuclear cataracts in the ocular lenses of subjects with AD. Here, we investigate the hypothesis that related AD-linked Aβ pathology underlies the distinctive lens phenotype associated with DS. Ophthalmological examinations of DS subjects were correlated with phenotypic, histochemical, and biochemical analyses of lenses obtained from DS, AD, and normal control subjects. Evaluation of DS lenses revealed a characteristic pattern of supranuclear opacification accompanied by accelerated supranuclear Aβ accumulation, co-localizing amyloid pathology, and fiber cell cytoplasmic Aβ aggregates (∼5 to 50 nm) identical to the lens pathology identified in AD. Peptide sequencing, immunoblot analysis, and ELISA confirmed the identity and increased accumulation of Aβ in DS lenses. Incubation of synthetic Aβ with human lens protein promoted protein aggregation, amyloid formation, and light scattering that recapitulated the molecular pathology and clinical features observed in DS lenses. These results establish the genetic etiology of the distinctive lens phenotype in DS and identify the molecular origin and pathogenic mechanism by which lens pathology is expressed in this common chromosomal disorder. Moreover, these findings confirm increased Aβ accumulation as a key pathogenic determinant linking lens and brain pathology in both DS and AD

Demand for Zn2+ in Acid-Secreting Gastric Mucosa and Its Requirement for Intracellular Ca2+

Recent work has suggested that Zn(2+) plays a critical role in regulating acidity within the secretory compartments of isolated gastric glands. Here, we investigate the content, distribution and demand for Zn(2+) in gastric mucosa under baseline conditions and its regulation during secretory stimulation.Content and distribution of zinc were evaluated in sections of whole gastric mucosa using X-ray fluorescence microscopy. Significant stores of Zn(2+) were identified in neural elements of the muscularis, glandular areas enriched in parietal cells, and apical regions of the surface epithelium. In in vivo studies, extraction of the low abundance isotope, (70)Zn(2+), from the circulation was demonstrated in samples of mucosal tissue 24 hours or 72 hours after infusion (250 µg/kg). In in vitro studies, uptake of (70)Zn(2+) from media was demonstrated in isolated rabbit gastric glands following exposure to concentrations as low as 10 nM. In additional studies, demand of individual gastric parietal cells for Zn(2+) was monitored using the fluorescent zinc reporter, fluozin-3, by measuring increases in free intracellular concentrations of Zn(2+) {[Zn(2+)](i)} during exposure to standard extracellular concentrations of Zn(2+) (10 µM) for standard intervals of time. Under resting conditions, demand for extracellular Zn(2+) increased with exposure to secretagogues (forskolin, carbachol/histamine) and under conditions associated with increased intracellular Ca(2+) {[Ca(2+)](i)}. Uptake of Zn(2+) was abolished following removal of extracellular Ca(2+) or depletion of intracellular Ca(2+) stores, suggesting that demand for extracellular Zn(2+) increases and depends on influx of extracellular Ca(2+).This study is the first to characterize the content and distribution of Zn(2+) in an organ of the gastrointestinal tract. Our findings offer the novel interpretation, that Ca(2+) integrates basolateral demand for Zn(2+) with stimulation of secretion of HCl into the lumen of the gastric gland. Similar connections may be detectable in other secretory cells and tissues

Implications of using systematic decomposition structures to organize building LCA information: A comparative analysis of national standards and guidelines - IEA EBC ANNEX 72

Introduction: The application of the Life Cycle Assessment (LCA) technique to a building requires the collection and organization of a large amount of data over its life cycle. The systematic decomposition method can be used to classify building components, elements and materials, overcome specific difficulties that are encountered when attempting to complete the life cycle inventory and increase the reliability and transparency of results. In this paper, which was developed in the context of the research project IEA EBC Annex 72, we demonstrate the implications of taking such approach and describe the results of a comparison among different national standards/guidelines that are used to conduct LCA for building decomposition.Methods: We initially identified the main characteristics of the standards/guidelines used by Annex participant countries. The “be2226” reference office building was used as a reference to apply the different national standards/guidelines related to building decomposition. It served as a basis of comparison, allowing us to identify the implications of using different systems/standards in the LCA practice, in terms of how these differences affect the LCI structures, LCA databases and the methods used to communicate results. We also analyzed the implications of integrating these standards/guidelines into Building Information Modelling (BIM) to support LCA. Results: Twelve national classification systems/standards/guidelines for the building decomposition were compared. Differences were identified among the levels of decomposition and grouping principles, as well as the consequences of these differences that were related to the LCI organization. In addition, differences were observed among the LCA databases and the structures of the results. Conclusions: The findings of this study summarize and provide an overview of the most relevant aspects of using a standardized building decomposition structure to conduct LCA. Recommendations are formulated on the basis of these findings

A Comparative Review of existing data and methodologies for calculating embodied energy and carbon of buildings

In the Climate Change Act of 2008 the UK Government pledged to reduce carbon emissions by 80% by 2050. As one step towards this, regulations are being introduced requiring all new buildings to be ‘zero carbon’ by 2019. These are defined as buildings which emit net zero carbon during their operational lifetime. However, in order to meet the 80% target it is necessary to reduce the carbon emitted during the whole life-cycle of buildings, including that emitted during the manufacture of materials and components, and during the processes of construction, refurbishment and demolition. These elements make up the ‘embodied carbon’ of the building. This paper reviews the existing European and UK standards, methodologies, databases and software tools for the estimation of embodied energy and carbon of buildings. While there is currently no legislation requiring the calculation of embodied energy in buildings, voluntary standards are being developed by the European Committee for Standardisation Technical Committee 350 (CEN/TC 350). Based on BS EN ISO 14040 and BS EN ISO 14044, these define a four stage process-based life cycle assessment method to calculate the embodied energy in construction, with a compulsory ‘product’ stage and optional further stages for ‘construction’, ‘use’ and ‘end of life’. A further voluntary specification for the assessment of the life-cycle greenhouse gas emissions of goods and services, PAS2050, was introduced in the UK in 2008. It too uses a process-based assessment the environmental impact of a building calculated through this method can therefore be seen as the sum of the environmental impacts of the products and processes that have created the building. Other Life Cycle Assessment methodologies have been developed in this area, including input-output (I-O) and hybrids of process and input-output. The environmental impact of a building defined by an input-output based assessment in contrast to that by a process-based method, is seen as a proportion of the total impacts of the different economic sectors which have created the building. The I-O approach therefore inherently assigns responsibility for environmental impacts to a particular industrial sector. Process-based methods are more specific to the construction product, and more accurate within the limited boundaries used. However they omit the supporting services necessary for construction, including finance, insurance, government and organisational administration and all related office buildings. While I-O assessment overcomes the problems with process assessment by considering a complete system boundary, the assumptions of homogeneity and proportionality in particular limit its use for comparison of impacts from individual products. For the purposes of designing a low embodied energy building, the I-O approach is too broad-brushed and generic to be helpful. The hybrid approaches attempt to overcome the limitations of both the process and the I-O methods. There is some existing embodied carbon and embodied energy data. However, due to the lack of current regulations and the inherent complexity and diversity of the area, the available data are varied in scope and application. There are three main sources of data: 1. There are several databases which include embodied energy and carbon of standard building materials and components. Some of these are construction sector-specific, while others contain more general product data. These provide data for the ‘cradle to factory gate’ phase of the embodied energy. Manufacturers are also starting to develop their own Environmental Product Declarations (EPDs) which include this data, and several of these are publicly available. 2. Both commercial and in-house software tools have been developed to calculate whole life-cycle embodied energy for buildings and infrastructure projects. This is known as ‘cradle to grave’ assessment. 3. Detailed life cycle assessments of specific buildings, including housing developments and individual dwellings, have also been carried out by academic researchers. A review of the research literature shows a wide range for the calculated embodied energy. This range in reported figures is due to the use of diverse product data arrived at through different LCA methodologies, different boundaries and often for specific manufacturers, which are therefore non-comparable; different calculation methodologies for the LCA of the whole building; and different building construction and designs. Perhaps most crucially, in spite of the likelihood of an underestimation by current analysis methods, the results show that embodied energy and carbon of buildings can be a very significant absolute value, as well as an increasingly high proportion of the whole life energy and carbon. The existing databases and much of the literature provide data for the product stage (stage 1) of the process – that is for the embodied energy and carbon in the building materials. However there is less, very limited, data available for composite components such as windows, for services components and for innovative materials and products. There is also a particular shortage of data across the construction sector in the energy used and carbon emitted during transport to site (part of stage 1 in prEN 15804), stages 2 (construction), 3 (in use) and 4 (end of life). The commercial and in-house analysis tools also vary in the databases they use, in their LCA methods and in the boundaries assumed in analysis. Taking each of the missing calculations in turn, the calculation of the reduced impacts of transport to site of local construction materials will inform and support the European standard BS EN 15643 parts 3 and 4, which considers the social and economic sustainability of construction works. Some construction projects last for several years and have hundreds of workers on site carrying out energy intensive activities. The accurate prediction of energy use and carbon emissions during standard site operations for stage 2 of the life cycle is therefore a fundamental part of the calculation for whole life embodied energy. Separately the development of off-site construction systems has been heralded as a ‘sustainable’ solution; this can only be verified with the development of an accurate ‘carbon costing’ method for both on-site and off-site construction activities, enabling the accurate comparison of different techniques and materials. Furthermore there is a lack of general data on the carbon and energy savings to be made by site management operations such as reuse of subgrade rather than the import of new materials. While ongoing maintenance and repair can be considered as part of the operational energy requirements, as suggested by the Strategic Forum for Construction (SFfC) [15], the impacts of major retrofit and refurbishment works form part of stage 3 of the whole life embodied impacts of a building. A clear understanding of the service life of individual components is necessary for these to be calculated. Finally there is limited data on the energy used by demolition, reuse and recycling processes at the end of life of a building. While these may be less important for building types with a long expected lifetime such as UK housing, it is a key element of short expected lifespans such as stadia, where design approaches are often required to consider deconstruction and reuse of components. In conclusion, it is essential to measure the whole life embodied energy and carbon of buildings, as well as their operational energy and carbon emissions. The comprehensive development of a robust methodology, and a deeper understanding of its limitations, is a necessary prerequisite for this. Various initiatives to develop and collate data and tools and make them freely available are still in their infancy, and these should be encouraged by the construction industry. It is hoped that the forthcoming standardisation of EPDs should ensure that all manufacturers produce equivalent information for their products within a few years. However the diversity of products used within construction will mean that the LCA of individual buildings will remain complex. This review will guide the future development of a consistent and transparent database and software tool to calculate the embodied energy and carbon of buildings within the specific context of the UK. The research is being carried out as part of a project led by BLP Insurance, and with the support of the Technology Strategy Board and the Engineering and Physical Sciences Research Council (EPSRC). In the Climate Change Act of 2008 the UK Government pledged to reduce carbon emissions by 80% by 2050. As one step towards this, regulations are being introduced requiring all new buildings to be ‘zero carbon’ by 2019. These are defined as buildings which emit net zero carbon during their operational lifetime. However, in order to meet the 80% target it is necessary to reduce the carbon emitted during the whole life-cycle of buildings, including that emitted during the processes of construction. These elements make up the ‘embodied carbon’ of the building. While there are no regulations yet in place to restrict embodied carbon, a number of different approaches have been made. There are several existing databases of embodied carbon and embodied energy. Most provide data for the material extraction and manufacturing only, the ‘cradle to factory gate’ phase. In addition to the databases, various software tools have been developed to calculate embodied energy and carbon of individual buildings. A third source of data comes from the research literature, in which individual life cycle analyses of buildings are reported. This paper provides a comprehensive review, comparing and assessing data sources, boundaries and methodologies. The paper concludes that the wide variations in these aspects produce incomparable results. It highlights the areas where existing data is reliable, and where new data and more precise methods are needed. This comprehensive review will guide the future development of a consistent and transparent database and software tool to calculate the embodied energy and carbon of buildings