Existing benchmark systems for assessing global warming potential of buildings – Analysis of IEA EBC Annex 72 cases

Life cycle assessment (LCA) is increasingly being used as a tool by the building industry and actors to assess the global warming potential (GWP) of building activities. In several countries, life cycle based requirements on GWP are currently being incorporated into building regulations. After the establishment of general calculation rules for building LCA, a crucial next step is to evaluate the performance of the specific building design. For this, reference values or benchmarks are needed, but there are several approaches to defining these. This study presents an overview of existing benchmark systems documented in seventeen cases from the IEA EBC Annex 72 project on LCA of buildings. The study characterizes their different types of methodological background and displays the reported values. Full life cycle target values for residential and non-residential buildings are found around 10-20 kg CO$_2$e/m$^2$/y, whereas reference values are found between 20-80 kg CO$_2$e/m$^2$/y. Possible embodied target- and reference values are found between 1-12 kg CO$_2$e/m$^2$/y for both residential and non-residential buildings. Benchmark stakeholders can use the insights from this study to understand the justifications of the background methodological choices and to gain an overview of the level of GWP performance across benchmark systems

Existing benchmark systems for assessing global warming potential of buildings – Analysis of IEA EBC Annex 72 cases

Life cycle assessment (LCA) is increasingly being used as a tool by the building industry and actors to assess the global warming potential (GWP) of building activities. In several countries, life cycle based requirements on GWP are currently being incorporated into building regulations. After the establishment of general calculation rules for building LCA, a crucial next step is to evaluate the performance of the specific building design. For this, reference values or benchmarks are needed, but there are several approaches to defining these. This study presents an overview of existing benchmark systems documented in seventeen cases from the IEA EBC Annex 72 project on LCA of buildings. The study characterizes their different types of methodological background and displays the reported values. Full life cycle target values for residential and non-residential buildings are found around 10-20 kg CO2e/m2/y, whereas reference values are found between 20-80 kg CO2e/m2/y. Possible embodied target- and reference values are found between 1-12 kg CO2e/m2/y for both residential and non-residential buildings. Benchmark stakeholders can use the insights from this study to understand the justifications of the background methodological choices and to gain an overview of the level of GWP performance across benchmark systems.publishedVersio

Comparison of the environmental assessment of an identical office building with national methods

The IEA EBC Annex 72 focuses on the assessment of the primary energy demand, greenhouse gas emissions and environmental impacts of buildings during production, construction, use (including repair and replacement) and end of life (dismantling), i.e. during the entire life cycle of buildings. In one of its activities, reference buildings (size, materialisation, operational energy demand, etc.) were defined on which the existing national assessment methods are applied using national (if available) databases and (national/regional) approaches. The ?be2226? office building in Lustenau, Austria was selected as one of the reference buildings. TU Graz established a BIM model and quantified the amount of building elements as well as construction materials required and the operational energy demand. The building assessment was carried out using the same material and energy demand but applying the LCA approach used in the different countries represented by the participating Annex experts. The results of these assessments are compared in view of identifying major discrepancies. Preliminary findings show that the greenhouse gas emissions per kg of building material differ up to a factor of two and more. Major differences in the building assessments are observed in the transports to the construction site (imports) and the construction activities as well as in the greenhouse gas emissions of the operational energy demand (electricity). The experts document their practical difficulties and how they overcame them. The results of this activity are used to better target harmonisation efforts.IEA -International Association for the Evaluation of Educational Achievement(Slovenia

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

Occurrence of thyroid papillary carcinoma in young patients. A Chernobyl connection?

The risk of thyroid papillary carcinoma is increased by external radiation particularly in children under 15 years of age as shown by a marked increase in those exposed to radiation after Chernobyl. We were recently confronted in Belgium over a short period with four patients (3 F, 1 M) with papillary thyroid carcinoma who were aged 10 years, 2 months, 2 years and 6 years when the Chernobyl accident occurred. We thus raise the question of a possible relationship. The patients were aged 17, 11, 10, 19 years at presentation. They all presented fortuitously over 3 years which was a very unusual increase in our extensive experience in thyroid surgery (62 cases of thyroid cancer among 1014 thyroidectomies in adults vs 4 cases in 18 children since the Chernobyl accident in 1986). Two out of the four patients had psammoma bodies (identifiable on CT scanning and ultrasound) and thyroglobulin autoantibodies (TgAb). The first patient had positive lymph nodes at the time of surgery. The incidence of thyroid cancers in Belarus and Ukraine rose just 4 years after the Chernobyl disaster; because radioactive clouds passed over Belgium, we wonder whether the occurrence of thyroid cancer in our patients could be related to this irradiation. The mechanism of increased incidence of radiation-induced thyroid cancer is thought to be due to rearrangement of the tyrosine kinase domains of the RET and TTK genes. The other important similarities in our patients are the presence of psammoma bodies that can be visualized on radiological examination and the presence of TgAb that are more frequent in differentiated thyroid cancers. Whether or not these cases reflect an increased incidence in the population as a whole, clinicians must remain vigilant for this rare but curable cancer in young patients, especially if suggestive radiological features or TgAb are present

Systemic supply to a pulmonary arteriovenous malformation: potential explanation for recurrence.

A pregnant woman presented with hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome) and a single pulmonary arteriovenous malformation (AVM) that had been embolized 5 years previously. Partly due to pregnancy, recanalization of the aneurysm occurred with subsequent hemoptysis. Despite successful therapeutic reembolization of the afferent pulmonary artery, hemoptysis recurred 5 days later. At this time, recanalization of the pulmonary artery was not demonstrated by pulmonary angiography, but a systemic angiogram revealed a bronchial arterial supply to the pulmonary AVM. A systemic supply should always be sought in cases of recurrent hemoptysis after technically successful embolization of the feeding pulmonary artery