This article analyzes the feasibility of using construction and demolition waste (expanded polystyrene, ceramic, and concrete waste) in a gypsum matrix to manufacture plaster for interior coatings or for prefabricated elements for interior partitions. To do this, several gypsum specimens were prepared (4 × 4 × 16 cm) incorporating different percentages of waste based on the weight of the gypsum (25%, 50%, and 75% of ceramic, concrete, and a mixture of both). Reference samples were also produced (without additions) to compare the results obtained. The compounds with the best performance were selected and lightened by preparing other samples in which 1/3 and 2/3 of the volume of ceramic, concrete, and mixed waste were replaced with expanded polystyrene (EPS). All samples were tested in the laboratory and the following physical and mechanical characteristics were determined: density, surface hardness, flexural strength, compressive strength, capillary water absorption, and thermal conductivity. Several applications were proposed for the selected compounds. A gypsum block with a sandwich configuration was obtained (40 × 20 × 10 cm) using the optimum compound. The block was further tested regarding its density and compression strength. A comparative analysis showed that it is possible to produce materials with a gypsum matrix by adding ceramic, concrete, and EPS waste, improving the behavior of the traditional gypsum and enabling them to be applied in various construction applications. These applications have a lower environmental impact than ordinary ones because they use less primary raw material, due to the reuse of waste.

The need to diminish the final amount of waste produced in construction and demolition processes in plants of concrete prefabricated products, has made us analyze the mechanical behaviour of concrete made with recycled aggregate coming from discarded concrete prefabricated units. The aim was to find a possible use for this recycled aggregate in different proportions in reinforced concrete and prestressed concrete, for prefabricated elements. Two situations using recycled aggregate have been studied: one of them, in natural state and subject to pre-saturation with selfcompacting H40 and H50 concrete, using as the only variable the substitution of the 4/12mm coarse aggregate in the following percentages: 0%, 20%, 50% and 100%. The results of the tests performed indicate that concretes with recycled aggregate coming from discarded prefabricated units can offer an excellent quality as structural concrete for future uses.

Demolition activity plays an important role in the total energy consumption of the construction industry in the European Union. The indiscriminate use of non-renewable raw materials, energy consumption, and unsustainable design has led to a redefinition of the criteria to ensure environmental protection. This article introduces an experimental plan that determines the viability of a new type of construction material, obtained from crushed brick waste, to be introduced into the construction market. The potential of crushed brick waste as a raw material in the production of building precast products, obtained by curing a geopolymeric blend at 60 °C for 3 days, has been exploited. Geopolymers represent an important alternative in reducing emissions and energy consumption, whilst, at the same time, achieving a considerable mechanical performance. The results obtained from this study show that the geopolymers produced from crushed brick were characterized by good properties in terms of open porosity, water absorption, mechanical strength, and surface resistance values when compared to building materials produced using traditional technologies.

This paper carries out a survey conducted among the construction agents in order to evaluate the effectiveness and viability of several best practice measures regarding construction and demolition waste (CDW) management in building rehabilitation works. This survey was developed considering that in rehabilitation works two well differentiated activities are carried out: those of the dismantling of the building (deconstruction activities) and those of the execution of the new construction (construction activities). Results of this survey show that among the highly rated best practices for the design phase “designing the building in order to help the recovery of the materials at the end of its use” can be highlighted, despite less than 25% of respondents usually implement this measure in their works. Moreover, according to BP during the construction phase, the results reveal that only 70% of respondents routinely implement the most valued measure “Hiring authorized companies for the management of CDW” and 60% the second “Respecting the manufacturer’s directions regarding the transport, collection and commissioning”.

Nowadays, nobody can deny that climate change is a reality and that the life cycle of buildings contributes greatly to that reality. Therefore, proposals such as the circular economy must be integrated into the construction sector. This article shows part of the results of a research project whose objective is to introduce circular economy criteria in building materials, seeking new uses for construction and demolition waste from buildings. In particular, this article analyses the possibility of replacing fibres currently used to reinforce cement mortars with recycled fibres. After consulting the bibliography, we can conclude that some studies analyse the behaviour of cement mortars reinforced with different types of fibres, but none has been found that analyses the behaviour of these mortars for the application of continuous coatings. For this purpose, a two-stage experimental plan is designed to test cement mortar samples with different types of fibres, recycled fibres and commercial fibres, taking into consideration the characteristics that these mortars have to comply to be applied as continuous coatings. Moreover, a detailed study about the porosity of these mortars and its influence on how the mortars behave with regard to compression, water vapour permeability and impermeability has been conducted. From the results obtained, it can be concluded that the mortars containing recycled fibres have very similar resistance, absorption and permeability values to those containing commercial fibres, so that they might be suitable for application as external coatings.