Advanced coatings for buildings

Based on five Special Issues in Coatings, this e-book contains a series of fifteen articles demonstrating actual perspectives and new trends in advanced coatings in buildings. Innovative materials and multiperformance solutions provide a basis, contributing also to better protection of buildings’ surfaces during the service life, and users’ wellbeing

Rehabilitation of renders of old buildings in Portugal: survey, supporting methodology proposal and case study

The main purpose of the research is to present a proposal for a methodology to support the rehabilitation project of renders of old buildings in Portugal. To achieve the objective it was considered essential to define the main types of participants and aspects to integrate the proposal. The research methodology consists in an inquiry presented to professional participants in rehabilitation, a market study of materials and products available in Portugal, the design of a methodology proposal and its application to a case study. The inquiry sample totals 24 answers from the targeted professionals. A sequence of relevant supporting procedures consists in the proposal, which aims to provide a supporting methodology to decide and project in this context and also to be tested with its application to the building. This proposal was applied to an old building with load-bearing stone masonry walls and air-lime based renders. It was concluded that the assessment of the building and external renderings’ condition, its diagnosis and of the supporting walls, the definition of intervention, the specification of materials to be used and performance requirements to comply, and also plans for conservation and periodic maintenance, are crucial. From the inquiry, compatibility between materials and complementary roles and points of view of different types of participants in rehabilitation must be highlighted. A proposal for a methodology to support the project could provide useful guidance particularly for architects and construction engineers, and improve the understanding of direct participants on site, therefore contributing for the correct implementation of intervention

Statistical survey of the pathology, diagnosis and rehabilitation of ETICS in walls

This paper presents a statistical survey on the pathology, diagnosis and rehabilitation of ETICS (external thermal insulation composite system) in walls. The development of an expert-knowledge inspection and diagnosis system for this type of cladding implied the creation of classification lists of anomalies, most probable causes, diagnosis methods and repair/maintenance techniques. The collection of data through field work where the tools developed within the proposed system were applied was the basis for this statistical survey. The field work consisted of the visual inspection of 146 façades with ETICS cladding located in various areas in Portugal and aged from 3 to 22 years. The data obtained enable anomalies to be related to their causes and so conclusions can be drawn on the best way to minimize the development of the former and eliminate the latter, at the design and application stages. The study further revealed the main sensitive issues of the cladding system during its service life, highlighting the importance of a correct maintenance plan

Reliability of in-situ diagnosis in external wall renders

This study focuses on the reliability of in-situ diagnosis performed on external rendered façades. This analysis was based on a set of parameters drawn from different visual observation, in-situ and laboratory testing techniques. The results were collected based on the previous inspections of 98 rendered façades of buildings and individual testing walls with different components, ages and degradation types. For that purpose, a reliability indicator was proposed and applied for better results interpretation of multiple testing techniques. In each case study, the parameters with higher reliability are defined. The final reliability indicator was established based on the average of three partial indicators, namely a reliability indicator for the established base criteria' uncertainty in laboratory testing (reference reliability indicator); a reliability indicator for the assessment techniques' uncertainty (verification method reliability indicator); and a reliability indicator for the results' uncertainty (number of the tests and their accuracy; reliability indicator of results obtained in-service). The reference parameters for each testing technique were synthesised. The relevant aspects, such as uncertainty associated with the reference parameter and type of verification method (quantitative, qualitative, and intervals), were defined. The analysis of the relationships between the parameters (exemplified for mechanical properties) and their correlation coefficients were assessed. Selection matrices were proposed that qualitatively identify the set of parameters that contribute to indirectly analyse the characteristics and performance relevant to the behaviour of the renders applied on façades. (c) 2020 Elsevier Lt

Argamassa industrial para a reabilitação de rebocos antigos

Argamassas 2014 - I Simpósio de Argamassas e Soluções Térmicas de Revestimento, 5-6 Junho, ITeCons, Universidade de CoimbraA crescente procura de argamassas técnicas que satisfaçam os requisitos impostos pelos edifícios antigos tem conduzido a indústria das argamassas a desenvolver e apresentar várias soluções para a área da reabilitação. Contudo este trabalho ainda se encontra num patamar em que é importante continuar a aprofundar e sedimentar conhecimentos nesta área. Concretamente o estudo do comportamento de argamassas com materiais mais sustentáveis que possam oferecer ao mercado produtos adequados, compatíveis com os edifícios em questão e economicamente viáveis, tem todo o interesse. Neste sentido, neste trabalho de investigação estudaram-se várias formulações industriais baseadas em cal aérea CL 90-S e em cais hidráulicas natural (NHL5 ou NHL3.5), com base num traço volumétrico 1:3 (ligante: agregado). Partindo de argamassas só de um desses ligantes (aéreo ou hidráulico), procedeu-se a substituições parciais pelo outro ligante, em teores de 25%, 50% e 75%, nas condições de cura preconizadas na norma EN 998-1. Era expectável que a cais hidráulicas naturais permitisse que as argamassas adquirissem valores de resistências mecânicas mais elevados nas primeiras idades, 28 dias, comparativamente às argamassas de cal aérea, de forma a adequar as características das argamassas aos prazos atuais de obra. Todas as formulações foram caracterizadas em termos de resistências mecânicas (28, 90 e 180 dias), aderência, massa volúmica, capilaridade e permeabilidade ao vapor de água. Verificou-se que, em termos de comportamento mecânico, algumas das as argamassas apresentaram valores satisfatórios. O mesmo se observa em termos de valores de aderência, comparativamente aos requisitos definidos na bibliografia e na norma EN 998-1. No entanto, argamassas com cais hidráulicas naturais e elevados teores de cal aérea parecem menos interessantes. Relativamente ao seu comportamento face à água observa-se que todas as formulações apresentam baixos valores de coeficiente de capilaridade e permeabilidade, o que demostra um bom desempenho, cumprindo plenamente os requisitos impostos. Considera-se que argamassas de NHL3.5 e baixos teores de cal aérea, a otimizar industrialmente, podem ser particularmente adequadas para aplicação em edifícios antigos

Multivariate Data Analysis of the Thermal Performance of Portuguese Residential Building Stock

The purpose of this study is to explore the relationship between solar orientation, age (constructive characterization) and energy performance of Portuguese residential building stock and to assess the usefulness of exploring the Portuguese National System for Energy and Indoor Air Quality Certification of Buildings (SCE) database through multivariate analysis techniques. By using principal components technique, it was possible to condense the residential units’ features to only four principal components (PC): solar orientation; constructive characterization; geometry and energy performance, making information more workable. Grouping the entities into Clusters with favourable and unfavourable solar orientation and old buildings allowed to dilute the particularities of each entity, facilitating the interpretation of the data through generalization. A regression model was generated in order to explore/confirm which factors influence summer comfort the most. Using this approach, it was illustrated that the exploration of the SCE database through multivariate data analyses has an enormous potential to convert data into knowledge

Use of Polycarbonate Waste as Aggregate in Recycled Gypsum Plasters

The use of gypsum as an indoor coating material for buildings is very extensive. This means that huge amounts of gypsum waste are generated daily worldwide. Therefore, many researchers in the last years have been working on the generation of new gypsum-related materials and products that incorporate recycled gypsum waste as a replacement for the commercial one. On the other hand, trying to reduce the large amounts of plastic generated globally each year, several studies have used different types of plastic waste as aggregates for the development of new construction and building materials. However, up to now, no previous studies have been found in which any type of plastic waste has been used as an aggregate in a recycled gypsum matrix. This paper presents a study in which two different types of waste were mixed for the development of new gypsum plasters: unheated gypsum waste from industrial plasterboard production (GPW) and polycarbonate (PC) waste from rejected compact discs (CDs) and digital versatile discs (DVDs). In this sense, the mechanical and thermal performance of plasters was evaluated. Finally, in order to evaluate the changes in the microstructure of the composites, a scanning electron microscopy (SEM) analysis was conducted. The results showed a good performance of the new composites when both types of waste were combined in the mixes. New lightweight eco-efficient plasters, completely recycled, with enhanced flexural strength (by 14.8%), compressive strength (by 26.8%), and thermal conductivity (42.8% less), compared to the reference material, were achieved

Impact of Water-Repellent Products on the Moisture Transport Properties and Mould Susceptibility of External Thermal Insulation Composite Systems

External Thermal Insulation Composite Systems (ETICS) are constructive solutions widely used to increase the thermal insulation in new and retrofitted buildings. However, these systems can present several anomalies due to their constant exposure to weathering agents and anthropic factors. Water is generally the major cause of degradation. Thus, the application of water-repellent products can minimize the appearance of anomalies and increase the durability of the systems. In this paper, acrylic-based and siloxane-based hydrophobic products were applied to ETICS, with the aim of assessing the compatibility, effectiveness, and durability of these products. The moisture transport properties and mould susceptibility were assessed through laboratory tests on untreated and treated specimens. The durability of the hydrophobic treatments was also evaluated through artificial aging tests (heat-cold and freeze-thaw cycles). Results show that the protection products generally decreased water absorption, slightly decreased the drying rate, and presented adequate water vapor permeability. After aging, the products still had reasonable effectiveness and, with one exception, improved the water vapor diffusion of the systems. Additionally, ETICS underwent an alteration in the finishing coat (possible modification of the porosity) due to the aging cycles. No clear linear correlation was found between the contact angle values and water absorption results, evidencing the influence of other factors related to the composition of the water-repellent products.This research was funded by Portuguese Foundation for Science and Technology (FCT) within research project PTDC/ECI-EGC/30681/2017 (WGB_Shield-Shielding building' facades on cities revitalization. Triple resistance for water, graffiti and biocolonization of external thermal insulation systems) and for the scholarship 2020.05180.BD (J. L. Parracha).info:eu-repo/semantics/publishedVersio

Durability of a New Thermal Aerogel-Based Rendering System under Distinct Accelerated Aging Conditions

The widespread application of innovative thermal enhanced facade solutions requires an adequate durability evaluation. The present work intends to assess the durability of a new aerogel cement-based rendering system through the adaptation of different accelerated aging cycles, such as heating-freezing, freeze-thawing, and heat-cold. Several mechanical properties and also capillary and liquid water absorptions were tested for uncoated and coated specimens. A decrease in the mechanical strength, especially after freeze-thaw cycles, was observed. However, the water action promoted the late hydration of the cement paste contributing to the densification of the matrix and, consequently, the increase of the adhesive strength. Additionally, a decrease in the dynamic modulus of elasticity and an increase in the Poisson's ratio were observed after aging, which indicates a higher capacity of the render to adapt to substrate movements, contributing to a reduction of cracking

ESTUDO COMPARATIVO ENTRE DIFERENTES TIPOS DE INTEGRAÇÃO DE SISTEMAS DE FACILITY MANAGEMENT E BUILDING INFORMATION MODELING

Facility management (FM) is a profession that contributes to maintaining, improving, and adapting buildings’ in-service conditions, involving multidisciplinary activities and relying on different technologies to promote a productive environment that supports the organization’s primary objectives (core-business). Also, various FM systems carry the information of FM. With the emergence of intelligent buildings, which embed most spaces with smart objects, building information modelling (BIM) has provided builders new opportunities to quality upgrade them at lower costs and shorter project duration, allowing information exchange between the various stakeholders involved. However, one of the biggest challenges to adopting the BIM approach is to ensure an efficient and robust exchange of information. Furthermore, as data amount drastically increases over time, it is vital to provide information consistency, traceability, and long-term archiving, so current solutions include integrating BIM and FM systems data. So, interoperability and automatic combination are the main reasons for common problems during a building life cycle, such as information asymmetry and data fragmentation. For this purpose, open-standard data models improve this integration between BIM models and FM systems. This paper discusses conventional approaches with potential and higher impact on FM data integration and their benefits and shortcomings.A Gestão de Instalações ou Facility management (FM) é uma atividade profissional que contribui para a manutenção, melhoria e adequação dos edifícios em condições de uso, envolvendo atividades multidisciplinares e contando com diferentes tecnologias para promover um ambiente produtivo que suporte os objetivos primordiais da organização. Além disso, vários sistemas específicos carregam as informações do FM. Com o aparecimento dos edifícios inteligentes, que incorporam a maioria dos espaços com objetos inteligentes, o Building Information Modelling (BIM) tem proporcionado aos gestores uma melhoria na qualidade das operações a custos mais baixos e num tempo mais reduzido, permitindo a troca de informações entre os diversos stakeholders envolvidos. No entanto, um dos maiores desafios para a adoção da abordagem BIM é garantir uma troca de informação eficiente e robusta. Ademais, devido ao elevado número de dados gerados ao longo do ciclo de vida de um ativo, é crucial fornecer consistência de troca de informação, rastreabilidade e um repositório a longo prazo, de modo a que as soluções atuais devam incluir a integração de dados de sistemas FM e BIM. Assim, a interoperabilidade e a integração automática são os principais motivos de problemas durante o ciclo de vida de um ativo, assim como a assimetria de informação e a fragmentação de dados. Para isso, modelos de dados de padrão aberto melhoram essa integração entre modelos BIM e os sistemas FM. Este artigo discute abordagens convencionais com potencial e maior impacto na integração de dados FM e seus benefícios e deficiências