Roof Types Research Articles

Modular Green Roofs and their Usage in the World

This article wants to introduce modular green roof systems and their usage in the world as well as in the Czech Republic, because green roofs are now used more than they have been constructed in any era in the history. Their construction is almost same as it was in previous centuries, so the obvious solution for their improvement is in the construction of themselves. Especially in the improvement of their construction time which should be lower with usage of modular system than at classical layer system of the green roofs. This research also wants to speak about construction system for individual types of green roof. Where the purpose of this article is to set optimal solution for modular green roof panel which will be economical and environmentally friendly.

컬러 태양전지 적용 유형에 따른 건축물 심미성 요소의 상관성 분석 : 색상 인자를 중심으로

Purpose: This research was conducted to analyze the aesthetics of solar cells considering the building facade aesthetics according to the recent research and development. In particular, the research focused on the analysis of the building facade aesthetics according to colored solar cells for BIPV (Building-Integrated Photovoltaic) as the solar cells of various colors were developed to be set as CBIPV (Colored BIPV). This research aims to derive the element of the facade to which CBIPV is applied. The effect of colored solar cells on aesthetics was analyzed by dividing into elevation and roof types. The purpose of this study is to discuss the design approach in the planning stage. Method: The SD (Semantic Difference) questionnaire analyzed the elevation aesthetics of colored solar cells. Also, multiple regression analysis is used for analyzing the effect of factors on the aesthetics of the facade. Aesthetic elements of the building facade were derived through principal component analysis, a factor analysis technique. Result: Five categories of elevation aesthetics of CBIPV were prepared, and seven significant factors were derived. The analysis discussed issues to consider during the planning phase. Through multiple regression analysis, the influence of each factor on the aesthetics was derived, and the characteristics of each color of the solar cell were analyzed.

Dynamic buckling analysis of cylindrical steel water storage tanks subjected to Kobe earthquake loading

AbstractCylindrical steel storage tanks are thin‐walled significant engineering structures. This study investigated the buckling conditions of ground‐supported cylindrical steel liquid storage tanks according to roof shapes and shell thicknesses. The roof shapes selected were open‐top, flat‐closed, conical‐closed and torispherical‐closed‐top tanks, and shell thicknesses were 4, 6 and 8 mm. These tanks may be exposed to several types of failure during earthquakes, such as elephant‐foot buckling, diamond‐shape buckling, overturning and uplift. Great financial loss and environmental damage can also ensue when steel liquid storage tanks are damaged in an earthquake. The seismic analyses were conducted under Kobe earthquake conditions for cylindrical steel tanks with different shell thicknesses and roof types. To investigate dynamic behaviour of the tanks accurately, the hydrodynamic response of each tank was divided into impulsive and convective components. Directional deformation and buckling results are presented for both impulsive and convective masses. As a result, the deformation of the tank is significantly reduced when the top of the tank is in the shape of a torispherical dome. The flat‐closed tank has a maximum directional deformation in both impulsive and convective modes. Results also show that when shell thickness was increased, buckling deformation decreased, but different deformation states were observed on the wall and roof components depending on the type of roof.

Sensitivity Analysis of Passive Design Strategies for Residential Buildings in Cold Semi-Arid Climates

Buildings are significant drivers of greenhouse gas emissions and energy consumption. Improving the thermal comfort of occupants in free-running buildings and avoiding active and fossil fuel-based systems is the main challenge in many cities worldwide. However, the impacts of passive design measures on thermal comfort in cold semi-arid regions are seldom studied. With the rapid urbanization and the widespread use of personalised heating and cooling systems, there is a need to inform building designers and city authorities about passive design measures that can achieve nearly optimal conditions. Therefore, in this study, a global sensitivity analysis of the impact of passive design parameters on adaptive comfort in cold semi-arid climates was conducted. A representative residential building was simulated and calibrated in Quetta, Pakistan, to identify key design parameters for optimal thermal comfort. The results list and rank a set of passive design recommendations that can be used widely in similar climates. The results show that among the investigated 21 design variables, the insulation type of roof is the most influential design variable. Overall, the sensitivity analysis yielded new quantitative and qualitative knowledge about the passive design of buildings with personalised heating systems, but the used sensitivity analysis has some limitations. Finally, this study provides evidence-based and informed design recommendations that can serve architects and homeowners to integrate passive design measures at the earliest conceptual design phases in cold semi-arid climates.

Integration of Recreational Spaces into Living Buildings Considering Ecological Aspects

The main goal of this article is to explore the modern approaches to solving problems of energy saving and environmental pollution by introduction recreation areas to the residential buildings. Reviewed the popular elements of green building - green roofs and vertical greening in residential buildings. Also, identified the advantages of greened roofs, studied the different types of roofs and various types of plants. The author considered vertical gardening and constructions (such as – suspended systems, modular lattices, metal mesh). The examples of foreign houses using vertical gardening confirm this type of landscaping as a unique. They can create new favorable spaces in an urban environment. So we can conclude that using of green roofs and vertical gardening is very relevant nowadays. They make urban accommodation more comfortable, increase aesthetic conditions of urban environment and they have good effect on human health.

The Uniqueness of the Saoraja La Tenri Bali Traditional House of South Sulawesi in Terms of its Building

The typical house of South Sulawesi is more typical of the Wajo Regency tribe called the traditional home of Saoraja La Tenri Bali. The purpose of this study was to look at the architecture of buildings in the Saoraja La Tenri Bali traditional house in the Wajo Regency. The results of this study illustrate that the traditional home of the Wajo Regency is a stilt house with a design of 101 poles because the number of poles supporting this house is 101 poles and is also one of the uniqueness of this traditional house. The primary building materials used are generally wood, a type of wood that is usually used ironwood to support the conventional house of Saoraja La Tenri Bali. The walls are composed of boards and a roof using a type of shingle roof. The structural system uses a home on stilts using support poles and uses a foundation; the house has 101 poles. Each pole weighs 2 tons made of ironwood from Kalimantan.

Green Roofs as Effective Tools for Improving the Indoor Comfort Levels of Buildings—An Application to a Case Study in Sicily

In the line of pursuing better energy efficiency in human activities that would result in a more sustainable utilization of resources, the building sector plays a relevant role, being responsible for almost 40% of both energy consumption and the release of pollutant substances in the atmosphere. For this purpose, techniques aimed at improving the energy performances of buildings’ envelopes are of paramount importance. Among them, green roofs are becoming increasingly popular due to their capability of reducing the (electric) energy needs for (summer) climatization of buildings, hence also positively affecting the indoor comfort levels for the occupants. Clearly, reliable tools for the modelling of these envelope components are needed, requiring the availability of suitable field data. Starting with the results of a case study designed to estimate how the adoption of green roofs on a Sicilian building could positively affect its energy performance, this paper shows the impact of this technology on indoor comfort and energy consumption, as well as on the reduction of direct and indirect CO2 emissions related to the climatization of the building. Specifically, the ceiling surface temperatures of some rooms located underneath six different types of green roofs were monitored. Subsequently, the obtained data were used as input for one of the most widely used simulation models, i.e., EnergyPlus, to evaluate the indoor comfort levels and the achievable energy demand savings of the building involved. From these field analyses, green roofs were shown to contribute to the mitigation of the indoor air temperatures, thus producing an improvement of the comfort conditions, especially in summer conditions, despite some worsening during transition periods seeming to arise.

Measuring the sustainability of wood consumption at the household level in Indonesia: Case study in Bogor, Indonesia

Abstract. Abdulah L, Suhendang E, Purnomo H, Mattangaran JR. 2020. Measuring the sustainability of wood consumption at the household level in Indonesia: Case study in Bogor, Indonesia. Biodiversitas 21: 457-464. Data on consumption of wood products at the end-user level does not yet exist. This is caused by variations in the shape of wood products and raw materials used. Meanwhile, information on the level of consumption per capita is needed to measure sustainability consumption at the household level, determine the volume of wood production and carbon storage in wood products in the household. The novelty of this study is in method for measure wood product consumption. The aim of this study was to estimate the level of wood consumption at the household level in the form of use for construction and furniture. The method used was a survey of wood products at the industrial level and to make a database and then confirmed to households to determine the level of consumption. The results showed that wood products in the household are divided into 2 main parts namely construction and furniture. The level of wood consumption varied greatly depending on the type of roof, the number of doors and windows and the amount of furniture used. The level of consumption in Bogor reached 0.1 m3 per capita. This consumption was influenced by the time of use and the size of family.

The Role of the Extensive Green Roofs on Decreasing Building Energy Consumption in the Mediterranean Climate

Buildings portion in global energy consumption is 40%, and in the building envelope, the roof is a crucial point for improving indoor temperature, especially in the last and second last floors. Studies show that green roofs can be applied to moderate roof temperature and affect the indoor temperature in summer and winter. However, the performance of green roofs depends on several parameters such as climate, irrigation, layer materials, and thickness. In this context, the present research deals with a comprehensive experimental analysis of different thermal impacts of green roofs in summer and winter in a Mediterranean climate. Measurements carried out in one year in three different types of green roofs with different thicknesses, layers, and with and without the insulation layer. The analysis determined the possible period that indoor cooling or heating might be required with and without green roofs and demonstrated the positive impact of green roofs in moderating the roof temperature and temperature fluctuations, which in summer was remarkable. In conclusion, since in the Mediterranean climate, the thermal differences between green roofs and conventional roofs in summer are much higher than winter, it seems that the green roof without an insulation layer would show better performance.

Combating Climate Change-induced Heat Stress: Assessing Cool Roofs and Its Impact on the Indoor Ambient Temperature of the Households in the Urban Slums of Ahmedabad.

Background:The rising global temperature and frequent heatwaves are the adverse effects of climate change. The causalities and ill impacts of the heat stress were higher among the slum dwellers because of the vulnerable household structures, which were made by heat-trapping materials like tin sheets, cement sheet (asbestos), plastic, and tarpaulin. The houses are not only dwellings but also a source of livelihood for many slum dwellers as they are involved in home-based work. The increase in the temperature of more than 40°C severely affects health and increases energy expenditures.Objective:The present study conducted to identify the efficient cool roof technologies that reduce indoor temperature of the households and improve the heat resilience of dwellings located in the urban slums of Ahmedabad.Methodology:The performances of cool roof interventions were compared with the nonintervention - roof types, namely, tin, asbestos/cement sheet, and concrete. Relative humidity/temperature data loggers (Lascar EL-USB-2-LCD, Sweden) were used to measure the indoor ambient temperature and humidity. The questionnaire-based survey also has been conducted to understand the socioeconomic status and the perceptions related to roofing and health.Results:The results revealed that selected cool roof technologies including Thermocol insulation, solar reflective white paint on the outer surface of the roof, and Modroof are effectively reducing the indoor temperature as compared to the nonintervention roofing.Conclusion:Cool roof technologies have a wider scope as number of informal settlements are increasing across the cities in India and other developing countries. The governments may not able to provide proper housing to all these inhabitants due to various reasons including the land tenure of the habitats. Validated cool roof technologies can be promoted as these structures are not requires legal sanctions and easily dismantled and installed in multiple places and safeguards the investment of urban poor.

Numerical Simulation of the Supporting Effect of Anchor Rods on Layered and Nonlayered Roof Rocks

In order to clarify the influence of anchor bolts on the supporting effect of the layered weak roof and surrounding rock of nonlayered roof with good integrity, the mechanical model of the roadway with nonlayered homogeneous roof and layered weak roof was established using FLAC3D. The distribution characteristics of the stress field and the displacement field of the bolt support are analyzed, and the supporting effect of the bolt on the roof of two types of roadways is studied. The research results show that when the original rock stress is not considered, the bolt support shows obvious tensile, compressive stress areas and positive and negative displacement areas in the surrounding rock of the roof of the roadway; when the original rock stress is taken into account, the tensile and compressive stress zones and the positive and negative displacement zones of the anchor support in the surrounding rock of the roof plate disappear obviously. The effect of the bolt support on the stress field and plastic area of the surrounding rock of the two types of roadway roof is not obvious. However, it has a significant effect on suppressing discontinuous deformation such as delamination and sliding between layered roof rocks. The delamination phenomenon between rock layers disappeared obviously, and the range of each numerical curve of the displacement field of the surrounding rock in the anchoring area was significantly reduced. However, the effect of the anchor support on continuous deformation control such as elastoplastic deformation of roof rock of nonlayered roadway is very limited. There is almost no change in the displacement field curve in the depth of the roof‐surrounding rock. Only the shallow surrounding rock displacement field curve range has decreased.

Analysis of roof greening technology impact on rain and meltwater retention

Over the past 20 years, a large number of studies have been published on reducing storm runoff by various types of green roofs. This article analyzes the results of experimental studies presented in 39 publications on green roof runoff reduction in a climate similar to the climate of Russia: in Canada, the USA, Finland, Norway, France. An analytical review found that the ability of green roofs to retain rainfall varies from 20 to 99.5% depending on climatic conditions (duration and intensity of rains, duration of dry periods, solar radiation, temperature and humidity, wind conditions), the properties of green roof layers (moisture capacity of the substrate and a drainage layer, the substrate thickness), the type of vegetation, the geometry of a green roof (slope and orientation). Green roofs can be a useful tool for reducing urban storm water runoff. However, in order to ensure high efficiency, it is necessary to use green roof technology with other measures to reduce runoff.

On the investigation of providing space truss roofs with ductility until failure under monotonically increasing vertical loads

The aim of this paper is to investigate the nonlinear behavior of space truss roofs subject to different load accumulation forms considering the effect of initial imperfection and slenderness ratio of the truss members. For this, a typical space truss roof using MERO-connection type with flat double-layer was selected as a sample. 3D model of the roof was developed and analyzed by using OpenSEES. Nonlinear behavior of each typical bar of the space truss roof, which, was mainly composed of particular sub-elements such as a tubular element, bolts, sleeves and spheres was represented by a single truss bar. Axial load-displacement relationship of each single truss bar was obtained from nonlinear analysis performed under reversal cyclic loading. Besides, three different types of load distribution that simulates accumulation of rainwater or drifted snow were taken into account as an external load acting on upper layer of the roof system. Analyses results showed that load carrying capacity of the space truss roofs was susceptible to the form of accumulation and reduces abnormally when the accumulation, in particular, occurred locally. Furthermore, failure mode of the system designed with optimal solution was dominated by buckled truss bars and brittle failure occurred. Also initial imperfection had a negative effect on the members in compression.

Anatomical variations of paranasal sinus and ethmoid roof type on computed tomography in patients admitted to the emergency department with migraine headache

Anatomical variations of paranasal sinus and ethmoid roof type on computed tomography in patients admitted to the emergency department with migraine headache

Rural Harvested Rainwater: Effect of Roof Types and its Design on Water Quality and Health: A Case for CBP Approach in Anambra State

Rural Harvested Rainwater: Effect of Roof Types and its Design on Water Quality and Health: A Case for CBP Approach in Anambra State

A Study on the Types of Rural Housing in the Taean Peninsula with a Special Focus on the Roof Types and Materials

A Study on the Types of Rural Housing in the Taean Peninsula with a Special Focus on the Roof Types and Materials

Comparison of heat gain values obtained for building structures with real and constant properties

The magnitude of energy consumption due to heating and cooling of buildings has led to the demand for increasing the thermal performance of building structures. Many investigations are presented in literature arguing to find the effect of each thermophysical property on the thermal characteristics of building components, while the properties have been assumed as independent of each other. In this context, this paper focuses on the effect of each property on heat gain value utilizing relationships between the measurement values of thermophysical properties of building structures. In previous study, 102 new wall samples were produced, their thermophysical properties were tested and expressions among these properties are obtained. In this study, the heat gain values through the structures are computed using solution of transient heat transfer problem by using both the obtained expressions between the thermophysical properties and assumptions proposed from the literature. Results obtained for varying and constant thermophysical properties have been compared with those values presented in literature. The results show that the assumptions are not realistic in a significant number of cases. Moreover, if one of the thermophysical properties of a material is known, heat gain values can be calculated easily for the selected wall or roof types.

Estudio experimetal del efecto hidrológico de cubiertas verdes para su utilización en el área metropolitana del Gran Resistencia

Se presentan los resultados preliminares de un estudio sobre modelo físico, referidos a la eficacia y eficiencia hidrológicas de cubiertas verdes para su utilización en el Área Metropolitana del Gran Resistencia (AMGR), Chaco. Las cubiertas verdes de tipo extensivas son sistemas que se colocan sobre techos tradicionales para disminuir los efectos de la impermeabilización del suelo urbano, buscando laminar los hidrogramas de escurrimiento que se generan. Están compuestas por varias capas construidas con distintos elementos, con características y propiedades diferentes, estando la capa superior constituida por un sustrato orgánico, de poco espesor, que permite el crecimiento de vegetación de bajo porte y por el que recibe el nombre de cubiertas verdes. El aumento de la impermeabilización asociada a la creciente urbanización, la baja pendiente natural del terreno y su localización en una zona de riesgo hídrico hacen propicia la implementación de este sistema en las ciudades que conforman el Área Metropolitana del Gran Resistencia como una medida de mitigación que permitiría minimizar los efectos de precipitaciones de elevada intensidad, reduciendo y retardando el agua de escurrimiento directo, colaborando a evitar (o por lo menos minimizar) los anegamientos provocados por las lluvias. En el presente trabajo se buscó evaluar cualitativa y cuantitativamente el efecto de este tipo de techos. Para ello, se construyó un modelo físico de la cubierta extensiva, utilizándose además otra de tipo plana tradicional como contraste. Los resultados preliminares obtenidos mostraron un notorio efecto amortiguador y retardador del escurrimiento de este tipo de cubiertas.

Combining Hydrologic Analysis and Life Cycle Assessment Approaches to Evaluate Sustainability of Water Infrastructure: Uncertainty Analysis

The goal of this research is identifying major sources of uncertainty of an environmentally-sustainable urban drainage infrastructure design, based on hydrologic analysis and life cycle assessment (LCA). The uncertainty analysis intends to characterize and compare relative roles of unreliability, incompleteness, technological difference, and spatial and temporal variation in life cycle impact assessment (LCIA) data, as well as natural variability in hydrologic data. Uncertainties are analyzed using a robust Monte Carlo simulation approach, performed by High Throughput Computing (HTC) and interpreted by Morse-Scale regression models. The uncertainty analysis platform is applied to a watershed-scale LCA of rainwater harvesting systems (RWH) to control combined sewer overflows (CSOs). To consider the watershed-scale implications, RWH is simulated to serve for both the water supply and CSO control in an urban watershed in Toledo, Ohio, USA. Results suggest that, among the studied parameters, rainfall depth (as a hydrologic parameter) caused more than 86% of the uncertainty, while only 7% of the uncertainty was caused by LCIA parameters. Such an emphasis on the necessity of robust hydrologic data and associated analyses increase the reliability of LCA-based urban water infrastructure design. In addition, results suggest that such a topology-inspired model is capable of rendering an optimal RWH system capacity as a function of annual rainfall depth. Specifically, if the system could capture 1/40th of annual rainfall depth in each event from rooftops, the RWH system would be optimal and, thus, lead to minimized life cycle impacts in terms of global warming potential (GWP) and aquatic eco-toxicity (ETW). This capture depth would be around 2.1 cm for Toledo (given an 85 cm/year rainfall and 200 m2 typical roof area), which could be achieved through an RWH system with 4.25 m3 capacity per household, assuming a uniform plan for the entire studied watershed. Capacities smaller than this suggested optimal value would likely result in loss of RWH potable water treatment savings and CSO control benefits, while capacities larger than the optimal would likely incur an excessive wastewater treatment burden and construction phase impacts of RWH systems.

An investigation on external airflow around low-rise building with various roof types: PIV measurements and LES simulations

In this study, the influence of different roof shapes on the airflow around isolated low-rise buildings is investigated with particle imaging velocity (PIV) wind tunnel experiments and large eddy simulations (LESs). PIV measurements are conducted in an atmospheric boundary layer wind tunnel for obtaining the mean velocity, fluctuating velocity component and time-averaged vortical structure around three low-rise buildings. The results provide a useful database for validation of an LES numerical model. Next, LES simulations are employed for solving the flow fields. Then, the performance of LES prediction is quantitatively evaluated based on the PIV database. Finally, the influences of the various roofs on the flow characteristics around buildings are analysed. The results illustrate that the LES numerical predictions show good agreement with the experimental results for all models. However, the predicting performance is largely related to the roof shape: A flat roof with a simpler geometry results in better prediction performance than more complex geometries do. The roof shapes remarkably affect the surrounding wind conditions at the pedestrian level. The area of low wind velocity (Ri < 0.2) in the wake region of the stepped model is by far the smallest at a wind direction of 180°. The size of a horseshoe vortex formed at the front of the model is positively correlated with the upwind height. The turbulence energy downstream is approximately concentrated around the non-dimensional frequency of 0.10, and the probability density functions of the velocity component at the monitor points approximately obeyed a normal distribution, with a weak skewness and kurtosis fatness.