Building insulation is commonly realized using materials obtained from petrochemicals (mainly polystyrene) or\ud from natural sources processed with high energy consumptions (glass and rock wools). These materials cause\ud significant detrimental effects on the environment mainly due to the production stage, i.e. use of nonrenewable\ud materials and fossil energy consumption, and to the disposal stage, i.e. problems in reusing or\ud recycling the products at the end of their lives. The introduction of the concept of “sustainability” in building design\ud process encouraged researches aimed at developing thermal and acoustic insulating materials using natural\ud or recycled materials. Some of them, such as kenaf or wood fiber, are already commercialized but their diffusion\ud could be further improved since their performance is similar to the synthetic ones. Others are currently under\ud study and their development is only at an early stage. The goal of the paper is to report a state of the art of building\ud insulation products made of natural or recycled materials that are not or scarcely commercialized. Comparative\ud analyseswere carried out considering in particular thermal characteristics in terms of thermal conductivity, specific\ud heat and density. Data on the acoustic performance of the materials were also reported. Life Cycle Assessment\ud data were finally collected, in order to put in evidence the environmental advantages of these materials.\ud Particular attention was paid to researches focused to exploit local materials and even industrial byproducts,\ud since these approaches respectively limit transportation and disposal impacts

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Acoustical sustainable materials, either natural or made from recycled materials, are quite often a valid alternative to traditional synthetic materials. The production of these materials generally has a lower environmental impact than conventional ones, though a proper analysis of their sustainability, through Life Cycle Assessment procedures, has to be carried out. Airborne sound insulation of natural materials such as flax or of recycled cellulose fibres is similar to the one of rock or glass wool. Many natural materials (bamboo, kenaf, coco fibres) show good sound absorbing performances; cork or recycled rubber layers can be very effective for impact sound insulation. These materials also show good thermal insulation properties, are often light and they are not harmful for human health. Furthermore, many of these materials are currently available on the market at competitive prices. There is however a need to complete their characterization, both from an experimental and a theoretical point of view, and especially to propose a standard and unique procedure to evaluate their sustainability. The paper presents an updated survey on the acoustical properties of sustainable materials, both natural and from recycled materials, including mixed and composite materials and systems such as green roofs and green walls, and is completed by a wide selection of recent related bibliography.

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applications in buildings and road barriers. Therefore, the production of these materials is a valid alternative to the disposal into landfill or incineration of used tyres. This paper presents the results of sound absorbing coefficient measurements of several samples manufactured at the Acoustics Laboratory of the University of Perugia. The sound absorbing panels were produced by mixing rubber crumbs and an adequate binder in a proper proportion and then by compacting the obtained mix. The methodology used to evaluate the coefficient of absorption coefficient is indicated in ISO 10534-2 standard, thanks to an impedance tube. The influence on the absorption performance of granules size, binder concentration, thickness and compaction ratio of the samples was investigated and an optimization process was carried out, in order to produce a sample with satisfying acoustical performance.

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Globally, artificial lighting accounts for a considerable part of electrical energy consumption in buildings. Hence, there is a need to design appropriate lighting scenarios for buildings in a way to reduce energy while meeting visual comfort requirements. This research aims to investigate the effects of applying different design strategies on lighting energy use and visual comfort level. Surface finishing reflectance, type, number and mounting height of luminaires are variables in the study. Lighting design software DIALux evo 7.0 provides simulations of a real scale room according to different scenarios whose models were calibrated and validated using experimental field data. The findings indicate that the type of luminaire is the most decisive parameter in quantity and quality of light in an indoor environment. However, increasing the indoor surface reflectance plays a key role in improving energy efficiency and visual comfort. The results show the possibility of electrical energy savings up to 45% by increasing surface reflectance properties. Finally, this paper stresses that there is no single design solution to guarantee both low energy demand and high visual quality, therefore integrating different strategies based on the type of task and the occupant’s activities is highly recommended.