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Highlights • Use of outdoor microclimate maps to compare different design options at urban scale. • Tool to evaluate impact on urban comfort of the place/city garden design. • Decision-making tool to improve urban climate design considering outdoor comfort. Abstract The study is aimed at evaluating the potential effects of alternative design solutions with different green elements on outdoor microclimate with relation to a real case study application. The study has been commissioned in the framework of the follow up of a design competition, launched by the Municipality of Cesena to reshape a square in the historic city center, when a public debate raised around the arrangement of trees and green surfaces envisaged by the architectural layout. Different options were considered and the design team and the public authorities sought for evidences on the deriving benefits in the respective configurations in order to properly drive the process. Thus the scientific research approach was applied to investigate the potential impacts according to a microclimate oriented perspective. The outcomes showed that green surfaces significantly improved the outdoor comfort conditions compared to original paved ones and that a minor contribution derived by the trees arrangement. The paper reports the applied methodology according to the specific context, the interpretation of results and how they have been translated into user friendly visualizations in order to make them understandable to a broader and non technical audience. [ABSTRACT FROM AUTHOR]

Studies on Outdoor Comfort in urban open spaces adopt several tools and software to simulate microclimate models, energy performances and the fluid-dynamics of winds. Air temperature, wind speed, relative humidity are the typical input data used by the software to evaluate comfort indexes such as the Predicted Mean Vote [PMV], the Physiological Effective Temperature [PET] or the Universal Thermal Climate Index [UTCI]. Among the available software, Envi-met provides accurate outputs as well as the PMV index space distribution starting from a three-dimensional microclimate model. However it is affected by some limitations for what concerns a user centered approach including the changes in human metabolic activity (met) or clothes (clo). This paper offers a synthesis of a study performed on ENVI-BUG, an Envi-met algorithmic app, to obtain a fast calculation and distribution of local PMV point-by-point displayed with mannequin representation. [ABSTRACT FROM AUTHOR]

Climate change and the deriving impacts on the built environment certainly represent one of the most challenging issue for several key players involved in shaping the cities of tomorrow. This is not simply a matter of adapting buildings to new requirements, but rather to rethink the way the urban fabric reacts to new and sometimes unpredictable phenomena. The process is related to increasingly evident extreme conditions in the summer time, that strongly improve the energy demand for cooling with negative impacts on the energy balance as well as on thermal comfort conditions of the end users and of urban population with severe implication on health and wellbeing. Outdoor comfort depends on a number of inter-related factors: the characteristics of the built environment, the relationship between materials and energy use, global climate change and local micro-climate: Temperature, Solar Radiation, Wind distribution, Wind Speed, Absolute and Relative Humidity. The objective of this specific study is to test the microclimate modeling of a city portion in a demo-case – a plot of building blocks with inner courtyards – as a tool for supporting the regeneration phase addressing technological choices and design solutions to improve outdoor comfort conditions. The outcomes of the performed envi-MET simulations, comparing the situation before and after intervention, are consequently discussed. In the specific case, the developed project involving the courtyard has led the Thermal Comfort perception, evaluated in terms of PMV, to shift from “very hot” (+3.50, +4.00 red zone) and “very very hot” (above + 4.50 violet zone) to “Warm” (+1.50, +2.00) at urban plot scale. [ABSTRACT FROM AUTHOR]

• Energy performance certificate (EPC) to c contribute in defining a energy poverty index. • Mapping building energy poverty risks to support policy actions for tackling energy poverty. • Merging GIS tool and EPC database to obtain city energy poverty maps at city (Bologna) level. Energy poverty is defined as the condition in which low-income people is no more able to face the costs of energy bills and consequently accept to live in cold and uncomfortable houses. In recent years the scientific literature about this specific issue has registered a significant growth, despite the problem is mainly approached from an econometric point of view to which instead medical, social and energy aspects have to be coupled. Recent EU policies like the Clean Energy Package and the Energy Building Performance Directive Recast III encourage to increase the efforts to tackle and eradicate the energy poverty. The paper approaches the problem focusing on one of its complementary causes: the building energy performance. The adopted methodology includes the calculation of the energy costs for each household, the definition of the energy poverty threshold, the calculation of the related building energy performance limit, otherwise leading to the energy poverty condition. These data, associated with the energy performance certificates, are used to create a GIS based mapping of the buildings potentially affected by energy poverty. Maps can be used to support decision making process in addressing appropriate strategies at urban level to tackle the energy poverty risk. The paper includes a case study in the city of Bologna where the proposed methodology is tested. [ABSTRACT FROM AUTHOR]

• Impacts of colour and reflectance variations of building façade on the outdoor microclimate in open spaces. • Outdoor microclimate analysis according to different material options for cladding the building façade. • ENVI-met simulation case study including multiple scenarios. Global warming affects the built environment with relation to its own characteristics, form, density. Heat waves effects would have limited effects if most of the cities would not be affected by Urban Heat Island that strongly increase their impacts (particularly on urban population). Does the choice of façade colours and materials contribute to this issue? The paper reports a research on a case study in Italy that tries to answer to this question comparing the trend in outdoor temperature increase closed to the building façade with relation to its colour and reflectance variations modelled by using Envi-met software. The outcomes point out that there is a correlation between the building façade reflectance and the temperature trend but this has a very limited influence on outdoor microclimate in open spaces as it varies in a range of less than 1 °C. [ABSTRACT FROM AUTHOR]