Dissertations / Theses on the topic 'Double-skin facade'

The main objectives of this research are (a) to investigate the thermal effect of double skin facades in office buildings in hot climates and (b) to propose guidelines for their efficient design based on this evaluation. The study involves the energy performance analysis of two buildings in India. A base case with the existing building skin was simulated for both the cities. The main source for the high cooling loads was found to be heat gain through windows and walls. This led to the evolution of a series of facade strategies with the goals of reducing heat gain, providing ventilation and day-lighting. The buildings were then simulated for their energy performance with the proposed double-skin strategies. Each of these strategies was varied according to the layers constituting the facade, the transparency of the facade and the orientation of the facade to which it is applied. Final comparisons of energy consumption were made between the proposed options and the base case to find the most efficient strategy and also the factors that affected this efficiency. The simulations were done using the building simulation software, Ener-Win. The double skin was simulated as per an approximate and simplistic calculation of the u-value, solar heat gain coefficient and transmissivity properties of the layers constituting the facade. The model relied on logically arrived at assumptions about the facade properties that were approximately within 10% range of measured values. Based on inferences drawn from these simulations, a set of design guidelines comprised of goals and parameters was generated for design of double-skin facades in hot climates typical to most of the Indian subcontinent. It was realized that the double-skin defined typically as a 'pair of glass skins separated by an air corridor' may not be an entirely energy efficient design strategy for hot climates. However, when used appropriately in combination with other materials, in the right orientation and with the right transparency, a double-layered facade turns out to be an energy efficient solution.

Visual integration of the building interior and exterior is one of the charms of today's architecture. The Double-Skin facade system is a technology that can reduce the drawbacks of using glass in a building's elevation. In fact, the double-skin façade (DSF) offers transparency while reducing energy consumption when compared to single-skin systems in cold and moderate weather conditions. However, there is no clear evidence of how the system will perform in hot climate conditions. In this research, a testing procedure was established to experimentally evaluate the performance of the double-skin façade system, data was collected to create multiple regression models, and then evaluate the double-skin façade's performance and compare it to a single-skin system in hot arid climate conditions.
Doctor of Philosophy
Improving the quality of indoor environments is a main goal in today’s architecture. Towards this goal, the use of glass and curtain walls is common in office buildings. The building façade is a key factor for the amount of energy consumed to reach comfort levels in the building. That is, because facades influence lighting, glare, heat gain, noise safety and energy usage. Therefore, the use of glass improves transparency which can interfere with comfort levels inside the building due to solar heat gain. The Double Skin façade system is widely adopted in Europe and has been shown to reduce energy used for heating in cold weather. In winter, heat losses can be reduced as the system’s intermediate cavity acts as a thermal buffer. However, there is no clear understanding of how the system will perform in hot arid climate conditions where cooling is the dominant operating mode. A Double Skin Façade can provide shading during the overheating period, while having the desired glass elevations sought by designers. This is due to ventilation and solar control devices located inside the system’s cavity. Being placed between the interior and the exterior glass panels, solar control devices are protected from the weather, which in return decreases its size. Furthermore, the additional glass panel allows windows in the system’s inner layer to be opened for natural ventilation. Unfortunately, the performance of the Double Skin Façade system for hot arid climate is not well documented. Therefore, the primary goal of this research is to compare the thermal and light performance of the Double Skin Façade system to a single façade system for hot weather conditions.

A smart building is an intelligent living space that elevates energy efficiency, comfort and safety. The word “smart” implies that the building would have a decision making system that can sense its conditions and reacts to them in an automatic and effective manner. Modem buildings contain many subsystems and, thus, to achieve automation, sophisticated sensing networks and robust control systems must be installed. The proposed research focuses on integrating several building systems—structural health monitoring (SHM), and structural and environmental controls—and explores synergy among them to improve efficiency and sustainability of buildings.

More specifically, an integrative, smart building system is developed by combining double skin façades and mass dampers in buildings to improve both safety and energy efficiency. Double skin façade systems protect and insulate buildings with two heavy glass layers between which air is allowed to flow for ventilation. By enabling movements in the outer façade skin, the façade can be used as a mass damper that reduces structural vibration and damage during earthquakes and wind storms. The added mobility also leads to innovative ways to control ventilation rate and improve energy efficiency by adjusting the gap size between the outer and inner skins.

In this dissertation research, the energy impact of the integrated system was first investigated. Then both passive and active structural control strategies were experimented and analyzed on a six-story shear building model. Results indicated the proposed system can significantly reduce structural response under the earthquakes excitations. In addition, the sensor networks and actuators introduced by the active structural control system were utilized for structural health monitoring purposes. The actuators provided harmonic excitations while the acceleration data were collected by the sensor networks to perform damage diagnosis.

Finally, since typical SHM systems require large networks of sensors that are costly to install, this dissertation research also examined using smartphones as alternative sensors. Using the aforementioned six-story experimental structure, a sensing system consisted of six smartphones was tested and proven effective in detecting structural damage. The experimental result demonstrates that further developments of smartphone SHM can lead to cost-effective and quick sensor deployments.

This research seeks to find a design solution for reducing the energy usage in high-rise office buildings in Singapore. There are numerous methods and techniques that could be employed to achieve the purpose of designing energy efficient buildings. The Thesis explores the viability of double-skin fa??ades (DSF) to provide natural ventilation as an energy efficient solution for office buildings in hot and humid environment by using computational fluid dynamic (CFD) simulations and case study methodologies. CFD simulations were used to examine various types of DSF used in office buildings and the behaviour of airflow and thermal transfer through the DSF; the internal thermal comfort levels of each office spaces were analyzed and compared; and an optimization methodology was developed to explore the best DSF configuration to be used in high-rise office buildings in the tropics. The correlation between the fa??ade configurations, the thermal comfort parameters, and the internal office space energy consumption through the DSF is studied and presented. The research outcome of the Thesis has found that significant energy saving is possible if natural ventilation strategies could be exploited with the use of DSF. A prototype DSF configuration which will be best suited for the tropical environment in terms of its energy efficiency through cross ventilation strategy is proposed in this Thesis. A series of comprehensive and user-friendly nomograms for design optimization in selecting the most appropriate double-skin fa??ade configurations with considerations of various orientations for the use in high-rise office buildings in the tropics were also presented.

This thesis contributes to the improvement of Double Skin facades' thermal performance in warm climates. A new design for DSF was proposed and evaluated using an experimental study on a scaled model and Computational Fluid Dynamics simulations. The proposed facade named IS-DSF (Interstitial slat-blind DSF) showed the capability to reduce overheating risk in the cavity due to two applied strategies: shading devices’ specific placement and wind-induced ventilation improvement. Finally, a framework was developed for the implementation of IS-DSF in warm climates applicable at the early stage of building design.

L'objectif de ce travail de thèse est de développer une méthodologie d'aide à la prise de décisions pour la conception énergétique de bâtiments durables. La méthodologie proposée est composée de : (1) une base de seize indicateurs caractérisant la performance énergétique du bâtiment, couvrant les trois dimensions du concept de la durabilité (aspects environnementaux, économiques et de confort des occupants) et suivant une approche de type cycle de vie ; (2) une méthode d'évaluation de ces indicateurs adaptée au niveau de précision de la connaissance du bâtiment dans les premières phases de projet ; (3) une logique de progression des décisions de conception donnée comme un modèle de répartition séquentielle des choix à effectuer à chaque phase de projet ; et (4) une base de connaissances d'éléments du bâtiment comprenant les données techniques, environnementales et économiques nécessaires pour la méthode d'évaluation. Cette méthodologie est destinée à être utilisée par la maîtrise d'œuvre d'un projet de construction, y compris architectes et bureaux d'études concernés par la performance énergétique, pour la conception de bâtiments de bureaux dans un contexte français. Un outil numérique d'évaluation a été mis en place comme une première application de la méthodologie proposée afin d'étudier ce qu'elle peut apporter au concepteur comme éléments d'aide à la prise de décisions. L'intérêt de la mise en œuvre de la méthodologie a été validé par divers cas d'étude à chaque stade du processus de conception : de la phase d'Esquisse à la phase d'Avant-Projet Détaillé. En particulier, l'intégration d'une façade double peau vitrée, dont l'impact sur la performance du bâtiment est encore peu maîtrisé, a été évaluée
The aim of this thesis work is the development of a decision-support methodology for the energy design of sustainable buildings. The proposed methodology consists of: (1) a set of sixteen indicators of energy performance, covering the three dimensions of the concept of sustainability (environmental, economic and user comfort aspects) and based on a whole life-cycle approach; (2) a framework for the calculation of these indicators, adapted to the level of knowledge and detail of buildings in the early design phases; (3) a decision making roadmap, proposed as a sequential model for structuring decision making throughout the design process; and (4) a knowledge base of building elements, compiling the necessary technical, environmental and economic data for evaluating energy performance. This methodology is aimed to assist architects and engineers who participate in the energy design of office buildings within a French context. An assessment tool has been developed as a first application of the proposed methodology in order to determine its contribution to the process of decision making. The methodology has been validated through various case studies at each stage of the design process: from the schematic design phase to the detailed design phase. In particular, the integration of a double skin facade, whose impact on building performance is still not fully understood, was assessed

The assignment of my diploma thesis was to design a polyfunctional building. Function of the building is based on the requirements of the Land Use Plan Brno, cadastral zone Židenice. The aim of the design was to improve the quality of public space in the area by creating parks, urban parterre with services, parking and by bringing missing features to the area. The building is located in the centre of the plot. The main facade is oriented to the main street. Design creates new parking on the ground and in the underground garage. On the first floor are rentable spaces for commerce and services. At 2nd and 3rd floor are open space offices with the possibility of spatial variability solutions. Architectural expression of the building is simple, consisting as a compact mass with parterre subsided, useful in terms of energetical sustainability. The facade of the building is made as a combination of a transparent double skin facade and opaque ventilated facade with fibre cement panels. Structural system is a precast concrete frame with a cast-in-place reinforced concrete shear core. Foundation is made as a reinforced concrete pads and strips. Ceiling is made of a precast prestressed hollow core slabs.

Notre investigation porte sur la simulation numérique des échanges thermo-convectifs dans un canal vertical ouvert à flux imposé. Cette étude rentre dans le cadre des recherches sur le rafraîchissement passif des composants PV intégrés au bâtiment. À cet effet, un code numérique en Différences Finies est utilisé pour résoudre les équations de Navier-Stokes et simuler la convection naturelle dans un canal. Ce problème reste difficile à résoudre parce que l'écriture des conditions aux limites d'entrée et de sortie reste un problème ouvert. Notre travail consiste d'abord en étude des différentes conditions aux limites pour le benchmark numérique AMETH. Les travaux réalisés ont permis de faire un premier choix sur les conditions aux limites. L'étude s'oriente ensuite sur la qualification et la quantification numériques et expérimentales pour deux fluides : l'air (convection-rayonnement) et l'eau (convection pure). Les résultats numériques/expérimentaux ont été comparés et les discordances ont été analysées. Plusieurs aspects phénoménologiques (rayonnement entre surfaces, variation des propriétés thermo-physiques, variation du nombre de Prandtl) ont été abordés afin de caractériser leurs influences respectives sur l'écoulement et le transfert thermique. Enfin, dans le but d'apporter des éléments de réponses sur les conditions aux limites dynamiques, nous avons simulé la convection naturelle d'un canal dans une cavité et tenté une modélisation
The present investigation deals with natural convection flow in a vertical open-ended channel with wall constant heat flux. This study falls under the framework of research on passive cooling of building integrated PV components. For this purpose, a numerical code developed with Finite Differences scheme is used to solve Navier-Stokes equations and simulate the natural convection in a channel. This problem is difficult to solve because the writing of inlet/outlet boundary conditions remains an open problem. First, our work consists of studying different boundary conditions for the the numerical benchmark AMETH. The work carried out has enabled a first choice of boundary conditions. The study then focuses on numerical and experimental quantification and qualification for two fluids : air ( convection - radiation) and water ( pure convection) . Experimental and numerical results were compared and discrepancies were analyzed. Several phenomenological aspects ( surface radiation, thermophysical properties variation, Prandtl number variation ) were discussed in order to characterize their influence on flow and heat transfer. Finally, in order to provide some answers on dynamical boundary conditions, we simulated natural convection of a channel inside a cavity and tried a modeling

Double-skin facades (DSF) have been implemented to harness benefits of increased energy efficiency, acoustic isolation, and access to natural ventilation. The continued innovation and implementation of these systems presents a need for revised structural standards that account for the differing airflow inlet and outlet configurations. Recent multi-story double-skin applications in North America are evaluated to document the current airflow and structural design methodologies utilized in practice. Multi-story double-skin configurations are the focus due to their prevalence in the United States, as learned following a review of 30 existing projects of which 21 had multi-story cavity partitioning. Preliminary simulations are performed using a two-dimensional transient simulation model where the variables considered included cavity aspect ratio (height/depth), ventilation geometry and permeability. These simulations revealed a prominent sensitivity to airflow inlet and outlet configurations, leading the research to extensive three-dimensional simulations with varied airflow configurations while holding other variables constant. To evaluate the structural response of multi-story double-skin facades, the effects of various airflow configurations on the pressure coefficient distribution are examined by using computational fluid dynamics to simulate a wind tunnel testing environment with scaled building geometries. The simulation method is first calibrated and reviewed against existing wind tunnel studies. A prototypical geometry is developed and three-dimensional steady-state computational fluid dynamic simulations are run for twelve configurations of airflow inlet and outlet combinations. The interior skin’s coefficient of pressure profile fluctuates considerably depending on the varying inlet and outlet configurations. Computational fluid dynamics with multiphysics software is evaluated to determine its potential effectiveness as a design tool for the determination of coefficients of pressure for double-skin facades. A set of guidelines is provided for 1) the evaluation process of coefficients of pressure for double-skin facades and 2) the design of various multi-story double-skin facades.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2000.
Includes bibliographical references (p. 267-273).
A new era of commercial buildings is emerging in Europe, driven by innovative designs in Germany, Britain and the Netherlands. Engineers and Architects are collaborating to design a new typology of buildings that are energy efficient, environmentally friendly, and architecturally sleek. The common elements are double-skin facades (DSF's) that employ sun shading and air movement between inner and outer glass membranes. The doubleskin or "airflow" facade is tied to mechanical systems either physically with ducts or by significantly affecting the performance of those systems by reducing building loads. As compared to conventional facade systems, DSF's are credited with providing a 30% reduction in energy consumption, providing for natural ventilation even in skyscrapers, and providing valuable noise reduction. They also create a visually transparent architecture that is impossible with conventional curtain wall facades with similar properties. However, most building owners, architects and engineers do not have the language or analytical tools to analyze the appropriateness of this technology to buildings of varying occupancies and configurations and in various climates. Double-skin facades are defined and a typological system is proposed as a quick reference tool that will aid in understanding and communicating about the family of solutions that lie within a family of technologies that fit the definition of DSF's. A series of case studies examines a range of DSF typologies and analyzes their goals, structure, and relative success. An analytical model is developed and described to provide a flexible tool for evaluating energy impacts of a wide range of double-skin facade designs. A parametric analysis suggests how this model may be used as a design tool by emphasizing key properties of DSF systems. The analysis and model is applied to the potential technology transfer to Tokyo, Japan.
by Daniel M.M. Arons.
S.M.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.
Includes bibliographical references (p. 47).
Double-skin airflow facades have been in use for several years in European countries. They have yet to be used in the United States. One factor is that there is a lack of a heat transfer model which can accurately predict facade performance. A model of performance has been developed by Daniel Arons. The goal of the work presented is to verify the model with experimentation on a small-scale facade. Sunlight was simulated with a 400 W metal halide High Intensity Discharge lamp. Outdoor summer conditions were simulated with a residential space heater. Two 1/8" thick panes of uncoated window glass, separated by 7", with 1" white aluminum blinds in the center, made up the facade structure. Air was driven through the channel at velocities up to 0.7 mis. The results of experimentation validate the model when no light is being projected on the facade. More work needs to be done to refine the model for cases where there is little or no airflow and also when light is shining on the facade. More specifically, the interaction between incident radiation and blinds should be refined. The greatest discrepancy between model and experiment occurs for the surface temperature of glass on the heated side.
by Jui-Chen Chang.
S.B.

Una proporción muy importante del presupuesto energético total de los países europeos es destinado al consumo energético del sector de la edificación, tanto en el ámbito doméstico como terciario. Debido a que esta tendencia continúa en aumento, es de vital importancia optimizar los edificios tanto desde el punto de vista de las envolventes térmicas, como de las instalaciones térmicas y las condiciones de operación y funcionamiento.

Esta tesis incide fundamentalmente en el diseño eficiente de la fachada, ya que éste es uno de los principales elementos que determinan el comportamiento térmico de los edificios. No sólo actúa como barrera entre las condiciones externas e internas, sino que el diseño eficiente de la misma, contribuye en forma relevante a la reducción del consumo de calefacción, aire acondicionado, ventilación e iluminación. Asimismo, es un elemento que incide notablemente en las condiciones de salubridad y confort.

Actualmente, existe un gran auge del uso de fachadas completamente hechas de vidrio, este tipo de construcción presenta una serie de ventajas arquitectónicas y estéticas, pero desde el punto de vista térmico pueden representar problemas de sobrecalentamientos y pérdidas de energía importantes, tanto en las áreas mediterráneas como en otras zonas climáticas. En este sentido, las fachadas de doble piel, compuestas por dos capas separadas por un canal de aire, usado para evacuar o aprovechar la energía solar absorbida por la fachada, pueden representar una opción de diseño válida para solventar esta problemática. Asimismo, este tipo de diseño puede producir unas condiciones de confortabilidad adecuadas debido a la reducción de las temperaturas de las superficies interiores de las fachadas.

El objetivo de esta tesis es el de contribuir al estudio de sistemas pasivos en general, y fachadas avanzadas en particular. Para ello, se ha desarrollado una herramienta numérica para la simulación de fachadas de edificios de simple y doble piel. La principal característica de este código es la de asumir un comportamiento unidimensional y transitorio. Las ecuaciones gobernantes (continuidad, momentum y conservación de la energía) son resueltas mediante la aplicación del método de volúmenes finitos. Las fachadas incluyen elementos arquitectónicos novedosos, como materiales de cambio de fase, aislamiento transparente, superficies selectivas y colectores solares con acumuladores integrados en la superficie de las fachadas. En la tesis, se describen las características de los modelos físicos y matemáticos implementados y se definen parámetros instantáneos e integrados que describen el comportamiento térmico de las fachadas.

Los modelos numéricos implementados han sido sujetos a procesos de verificación y validación en diferentes formas: i) por comparación de los resultados numéricos con los obtenidos para situaciones simplificadas que cuentan con solución analítica, ii) por comparación con parámetros globales tabulados en la literatura de ciertas configuraciones de fachadas, y iii) por comparación de los resultados numéricos con los obtenidos experimentalmente en celdas de ensayo sometidas a diferentes condiciones climáticas.

Se presentan resultados de estudios paramétricos de diferentes configuraciones de fachadas y aplicaciones del código numérico para la optimización del diseño de fachadas de edificios emblemáticos del entorno. Como acciones futuras, se prevé la conexión de este tipo de simulaciones con otras de más alto nivel, bidimensionales, para optimizar zonas concretas de las fachadas.
A significant proportion of the total national energy budget of european countries goes toward energy consumption in buildings, therefore the efforts addressed to optimize building's thermal behaviour are of vital importance. In this sense, facades play a fundamental role. Not only do they act as barriers between external and internal conditions, but they can also help to reduce the consumption of energy for heating, ventilation and air conditioning. Moreover, they can help to produce healthy and comfortable indoor conditions. The use of large, transparent areas in facades is a common current practice. Despite the architectural interest of these glazed areas, in Mediterranean climatic conditions they are responsible for building overheating. In these zones, double-skin envelopes made up of two layers of glass separated by an air channel -to collect or evacuate the solar energy absorbed by the facade- are considered to be a design option that could resolve this issue. In other climatic conditions, large heat losses may constitute the most determinant factor. Anyway, the comfort parameters are influenced by the large transparent areas, also in this design aspect, double skin facades may contribute to obtain more comfortable and pleasant living spaces.

The objectives of this thesis are to give a step forward in the study and numerical analysis of passive systems in general, and advanced facades in particular. A one-dimensional and transient numerical code for the simulation of double and single skin facades including advanced technological elements, like phase change materials, transparent insulation and facade integrated collectors-accumulators has been developed. The features of the physic and mathematical models implemented are described and instantaneous or integratedperformance parameters describing thermal behaviour of the facades are defined. The numerical models implemented within the numerical tool have been subjected to a verification and validation process in different forms: by comparing the numerical results with those obtained for simplified situations with analytical solutions, with tabulated global performance coefficients of simple façade configurations and with the results of other building simulation codes. Experimental research has been carried out in test cells situated at different geographical locations, thus they were subjected to different climatic conditions. The main objective of the developed numerical code is to simulate advanced facades in order to assess the long term performance, and to account with a virtual tool to test passive designs, including challenging innovations.

The applications of the numerical tool described in this thesis, for the optimisation of facades of real buildings are presented. As future actions, the link of the one-dimensional simulations produced by this numerical tool with a multi-dimensional simulation of specific zones of the facades is foreseen.

Purpose: The building sector accounts for 40 % of the total energy consumption in Sweden today, and the largest proportion is consumed during the operating phase. From the year 2020 and onwards, all new buildings should be erected as zero-emissionbuildings. The building’s design can reduce energy demands, but the current legal requirements do not favour energy-efficient designs. This study focuses on the design’s importance for the energy efficiency of buildings, i.e., energy-saving design. The impact of specific measures is difficult to calculate due to the complexity of reality. This study aims to highlight the measures that could reduce energy consumption in commercial buildings. Method: In order to provide answers to the issues stated in the report and to achieve the objective of the study, case studies are being conducted investigating three commercial buildings where deliberate decisions were made to use energy-reducing measures. Results and conclusions are based on qualitative interviews and literature studies. Findings: The energy-reducing design measures found to be of most importance used in the studied buildings are the form factor, the window portion and the thermal storage capacity. Moreover, significant savings are possible by carefully consider how solar energy can be limited or used in the building. Generally, buildings tends to become more technical, therefore technical knowledge early in the process is important to reach a good result. Economic incentives and clear objectives with right focus are also important for optimizing a building’s energy performance. The wording and the requirement levels in the Swedish building regulations highly controls the construction of energy efficient buildings. Implications: This study shows how energy efficient design is made today and provides an indication of what can be done and what should be prioritized. By imposing requirements on consumed energy instead of bought, energy efficient design could be favoured. Furthermore, this study suggests that a balance between windows, façade and solar shading are important energy-reducing measures. Regardless of selected energyreducing measures, a good performance is essential. Finally, this study shows that a methodical use of existing knowledge and technology makes a difference. Limitations: A lifecycle approach provides an overall picture of a building’s energy consumption. However, this study is based on the energy consumption during the operating phase. The result of this study does not take economic or aesthetic factors into account. This study is a comparative case study and is based on few but carefully matched cases. The selected cases are commercial buildings where deliberate decisions were made to use energy-reducing measures.

Predmet istraživanja načelno se odnosi na razmatranje koncepta dvostrukih ventilisanih fasada (DVF) i njihov uticaj na energetsku efikasnost objekta. Ovaj koncept predstavlja jedan od primera adaptivnih fasada. Plan istraživanja zasnovan je na eksperimentalnom radu (na realnom objektu) i na numeričkim simulacijama modela objekta. Rezultati eksperimentalnog dela istraživanja pokazuju na koji način zavise termičke osobine objekta sa DVF od trenutnih meteoroloških uslova. Takođe, ovi rezultati poslužili su za fino podešavanje modela i za postizanje što vernije slike realnog objekta. Kriterijum prihvatljivosti, kada je model potvrđen, definisani su sa preporučenim statističkim indikatorima. Na taj način, formiran model u daljoj analizi je korišćen za definisanje sezonskih operativnih strategija. Rezultati simulacija za sve predložene operativne strategije, ocenjuju kakav je njihov uticaj na potrošnju energije za grejanje i klimatizaciju posmatranog objekta. Poređenjem sa modelima objekta sa tradicionalnom fasadom, pokazana je opravdanost primene koncepta DVF u klimatskim uslovima Beograda.
Research generally refers to the consideration of the concept of a double skin facades (DSF) and their impact on energy efficiency of the building. This concept is an example of adaptive facades. The research plan is based on experimental work and on the numerical model simulation. The results of experimental research works show how energy characteristics of the object with the DSF depend of current meteorological conditions. Also, these results were used to fine-tune the model to achieve as closely as possible the real presentation of the real building. The criterion of eligibility, when the model is verified, are defined with the recommended statistical indicators. Validated model in further analysis is used to define seasonal operational strategies. The simulation results for all proposed operational strategies, assess what is their impact on the building energy consumption for heating and air-conditioning. Compared to the models with a traditional facade, analysis show justification for the application of the concept of DSF in the climatic conditions of Belgrade.

Today, ever changing and advancing techniques of construction are constantly pushing the envelope of structural possibilities in the built environment. Although not new, the concept of Double-Skin Façades (DSF) finds increasing implementation with the advent of sustainable construction, aiming to reduce energy consumption to condition buildings whilst improving indoor air quality. As is the case with the traditional concept of the compartment fire, methodologies and assumptions on which our general understanding of the fire problem is based, did fundamentally not change. Inherently bound to this, is the concept of compartmentalisation, prescribing measures to avoid horizontal and vertical fire spread in buildings. A DSF, most commonly featuring a ventilated cavity between curtain wall and the secondary glass façade at an offset, is prone to drastically alter fire and smoke behaviour once able to enter. Unlike curtain walls, the chimney-like aspect ratio of such façades is able to trap fire and combustion gases within the cavity, potentially compromising the integrity of the building perimeter above the fire. The current approach to this issue tends to focus on using non-combustible construction materials and the installation of sprinkler systems to avoid breakage of window panes in the first place. Another topic of interest is the weak connection between floor slab and curtain wall which can allow vertical fire spread to adjacent floors. Research has also been discussing the use of mullions to deflect the fire plume away from the façade. Even if useful in DSF’s, aesthetics and problems with functionality will most likely prevent mullions from being introduced into the DSF. However, very little relevant research actually investigated the fire-induced flow structure under these conditions so that properly informed design decisions can be made. The project at hand aims to understand hazards to the floors above and below the fire floor by experimentally investigating the governing processes by means of large-scale fire testing and small-scale salt-water modelling (SWM). The gathered data shall serve as a basis to discuss current spandrel and cavity design decisions. Results have been compared in terms of dimensionless numbers and demonstrate complex interactions between DSF cavity width and spandrel height, encouraging a discussion about the need of further research of this topic.

Double Skin Facades (DSFs) have been developed as an alternative technology to improve the thermal performance of conventional fully glazed buildings. Nevertheless, there is little test information on the behaviour and real performance of DSFs. This is specifically the case when the facade has to perform under extreme or moderate summer conditions. The characteristics of thermal overheating of a specific type of DSF with various configurations and its practical control have not been subjected to systematic experimental and computational investigations. This research which is based on an existent load of knowledge, carried out experiments of a full-scale one-storey laboratory chamber of a selected type of Double Skin Facade in which a comparative analysis of the thermal performance is assessed, CFD simulations of the experimental model and a Field Case Study of an existing building in the United Kingdom is also monitored. The basic thermal behaviour in the facade cavity and adjacent room is investigated by a series of parametric studies and basic flow field investigations. Section models of the DSF chamber and the case building were made and modelled using CFD in order to visualise the thermal and airflow behaviour inside the DSF complementing the experimental and field work. The modelling work has demonstrated the feasibility and versatility of the technique for probing the flow and thermal behaviour of double skin facades. It was found that natural ventilation through the cavity by a series of controlled opening shafts on the upper and lower facade are effective means to reduce DSF overheating. It was also observed that the optical properties of cavity elements, cavity depth size, solar control and the basic operation of the facade are key issues to address in order to prevent overheating and additional heat loads from the facade.

The facade's configuration in hot arid areas is predicted to be responsible for up to 40% of the building's cooling loads. The increasing reliance of public buildings in Cairo on air conditioning systems indicates the failing role of the building envelope to perform its function as a moderator leading to an alarming increase in electricity consumption. Office buildings in Cairo consume 5-7% of the total national energy consumption. The need to reduce energy consumption in this sector targets benefits of reductions of electricity bills to building owners as well as reducing C02 emissions from the built environment due to increasing electricity generation. The lack of maintenance funds left the office building facades in a deteriorated state. This deterioration of image led to abandonment of buildings and loss of economic revenue. Double skin facades were investigated as a novel facade refurbishment option, targeting a multi criteria framework for facade refurbishment set in this thesis. To achieve the aim of the thesis, different facade technologies were simulated using a dynamic software (APACHE v.4.3.1) to understand their thermal performance. Quantitative results of simulations were parametrically examined to identify benchmark options for facade refurbishment to reduce building total cooling loads. Simulations results indicated up to 40% reductions in total cooling loads if a double skin facade with an outer reflective surface is used. Information generated from the simulation of single and double skin facade configurations were inducted into qualitative theories predicting human comfort aspects within the workplace. Three qualitative criteria underpinning the psychological comfort of occupants and its impact on productivity are set for balancing energy saving measures through facade refurbishment. These criteria are: the need for a view out, day light availability for non-task performances, and perceived control over the facade in work places.

The building industry makes up a considerable fraction of world&
#8217
s energy consumption. The adverse effects of a growing energy demand such as depletion in fossil fuel reserves and natural resources hassled the building industry to a search for new technologies that result in less energy consumption together with the maximum utilization of natural resources. Energy- and ecology-conscious European countries incorporated the well-being of occupants while conducting research on innovative technologies. In view of the fact that double-skin faç
ades offer a healthy and comfortable milieu for the occupants and use natural resources hence consume less energy they became a promising invention for all concerns. The analysis of the performance of the double-skin faç
ades and energy consumption is inconclusive at this time. However, based upon thermal performance analysis have been done so far, a double-skin faç
ade perform better and provide some energy reduction, particularly on the heating side cycle, from a standard double glazed unit wall. The aim of this study was to examine the relationship between double-skin faç
ades and building management systems in intelligent office buildings as they relate to energy efficiency issues thus to find out whether or not the integration of these systems into intelligent buildings provides optimization in energy performance and comfort conditions. The building for the case study, which is an intelligent office building incorporating a double-skin faç
ade was selected as one that promises high comfort conditions for the occupants with low energy consumption. The working principles of integrated faç
ade systems, together with their advantages and disadvantages were investigated by means of the case study. It was concluded that due to their high initial costs, these systems offer no real advantages for today. However with the inevitable exhaustion of fossil fuels that is foreseen for the future, these systems would become an innovative solution in terms of energy conservation.

The aim of this diploma thesis is to create a detailed design of a public library with cafeteria. The building is situated in the developing city area of Jihlava in the cadastral area of Horní Kosov. It has four storeys above ground and no basement floor. The 4th floor has a smaller net floor area than the rest floors. The building is designed also for disabled people. The expected number of employees is 18 and the number of visitors is 150 in a daily average. An entrance to the property is on the Vrchlického street. There is a parking lot in front of the building with a total capacity of 50 parking spaces including three parking spaces for disabled. The cafeteria and its facilities are situated in the ground floor of the building. Browsing area is situated in the second and third floor. The type of the structure is a frame structure with infill walls made of aerated concrete. The building has a double-skin facade. The cladding of the facade is made of fibre-cement boards. There is a curtain wall designed at some sections of the facade. The building has a warm flat roof with a parapet wall and interior roof drains.

L'objectiu general d'aquest treball és contribuir a l'avaluació de la transferència de l'energia en règim dinàmic de sistemes Fotovoltaics de doble pell Integrats en Edificis (EIFV) amb ventilació forçada sota condicions climàtiques exteriors reals. Per tant, un dels objectius d'aquest treball de recerca va consistir a recol.lectar dades experimentals sota condicions externes reals amb el “Test Reference Environment” (TRE) al Parc Científic i Tecnològic Agroalimentari de Lleida (PCiTAL). Es va dur a terme una llarga campanya de mesures on es van realitzar diversos experiments, amb diferents inclinacions i règims de ventilació. Un altre objectiu va ser estimar paràmetres físics desconeguts mitjançant l'ús de models d'identificació. Per aconseguir aquest objectiu, diversos models de caixa grisa estocàstics es van desenvolupar. Finalment, a partir de l'experiència adquirida durant el treball experimental, d'anàlisi i de modelatge, s'ha proposat la definició d'un entorn de prova “Test Reference Environment” estandarditzat per a les aplicacions de EIFV de doble pell.
El objetivo general de este trabajo es contribuir a la evaluación de la transferencia de la energía en régimen dinámico de sistemas de doble piel FotoVoltaicos Integrados en Edificios (EIFV) con ventilación forzada bajo condiciones climáticas exteriores reales. Por lo tanto, uno de los objetivos de este trabajo de investigación consistió en recolectar datos experimentales bajo condiciones externas reales con el “Test Reference Environment” (TRE) en el Parque Científico y Tecnológico Agroalimentario de Lleida (PCiTAL). Se llevó a cabo una larga campaña de medidas donde se realizaron varios experimentos, con diferentes inclinaciones y regímenes de ventilación. Otro objetivo fue estimar parámetros físicos desconocidos mediante el uso de modelos de identificación. Para lograr este objetivo, varios modelos de caja gris estocásticos se desarrollaron. Por último, a partir de la experiencia adquirida durante el trabajo experimental, de análisis y de modelación, se ha propuesto la definición de un entorno de prueba “Test Reference Environment” estandarizado para las aplicaciones de EIFV de doble piel.
The general aim of this work is to contribute to the energy dynamics assessment of mechanically ventilated double skin Building Integrated PhotoVoltaic (BIPV) systems under real outdoor weather conditions. Therefore, one of the objectives of this research work has consisted in collecting experimental data under real outdoor conditions in the Test Reference Environment (TRE) at the Lleida Agri-food Science and Technology Park (PCiTal). An extensive monitoring campaign has been carried out and several experiments, at different inclinations and ventilation regimes, have been performed. Another goal was to estimate unknown physical parameters by using identification models. To achieve this goal, several stochastic grey-box models have been developed. Finally, from the experience gained during the experimental, analysis and modelling work, the definition of a standardized set-up for a Test Reference Environment for double skin applications of BIPV has been proposed.

碩士
國立臺灣大學
土木工程學研究所
100
This dissertation discusses the design of double-skin facade (DSF), especially distance between two facades. It evaluates efficiency of DSF system based on a Vietnam case study. According to previous studies, the suggestion for range between two facades should be 0.22 – 2 meters. However, most researchers do not give the actual calculations in their researches. By using the Designbuilder software, this research tried to analyze the data from an actual building to draw the comparisons and conclusions in DSF ventilation system. In summary, my case study indicates that the optimal distance between two facade is 0.55 meters and it can be applied in similar designs and locations. The dissertation not only provides optimal distance between two facades but also provides suggestions in choosing materials, cavity design, ventilation and shading system design. The purpose of dissertation is to achieve the optimal design for typical double-skin facade building. Besides, to improve the accuracy of thesis’s results, the parameters from outside environment have been focused. Climate features, opposite building, ventilation system and the building’s dimension are the four factors concerned, which affect the accuracy of evaluations and results. The results show the change of energy saving effect of double-skin facade design in comparison with conventional building. By using the dissertation’s results, designer can reduce the time required for calculations and improve the efficiency of their design. Investment cost has been analyzed based on Vietnam case study building. However, this research does not give conclusions or suggestion for the economic efficiency of investment. The cost analyzing work serves for references and for further study’s purposes.

碩士
國立中央大學
營建管理研究所
101
雙層帷幕外牆是目前建築物外牆設計方法之一，此方法可直接提供舒適之室內溫度，以改善冷暖氣之能源消耗。本研究主要目的在於探討在潮溼與悶熱的台灣環境裡，運用自然通風與雙層帷幕外牆之設計，降低既有建築物室內冷卻之能源消耗。本研究運用DesignBuilderEnergyPlus作為模擬工具，分別針對兩棟台灣國立中央大學之既有校舍進行雙層外牆間之空隙與外牆材料變異之模擬，並研究參數改變後之能源差異。第一個模擬情境，僅就單層外牆與雙層外牆之最高受熱面進行數據蒐集與差異探討；第二個模擬情境，假設建築物所有外牆皆採用雙層外牆之設計之差異。在兩個情境模擬下，案例一顯示當採用1.2公尺之空隙設計與Low-E玻璃時，分別可節省31.28% 與34.69%之建築物室內冷卻能耗；案例二之結果亦顯示採用1.2公尺之空隙設計與Low-E (Low Emissivity) 玻璃，是能源效率最高之組合，分別可節省了11.94% 與21.26%之冷卻能耗。而在不同的模擬情境或參數改變下，案例一與案例二分別至少改善8.5MWh及15.33MWh之能耗。此模擬之結果顯示，即使在潮溼與炎熱的台灣夏季，雙層帷幕外牆設計仍具備一定之效能，亦可作為未來台灣建築物節約能源策略之一。

A Building Integrated Photovoltaic/Thermal (BIPV/T) system that consists of a mechanically ventilated, multi-skin facade, a between-the-panes venetian blind layer, and a between-the-panes Photovoltaic (PV) panel is considered. Ambient air is drawn in and forced to flow upward through the system. As air moves through the system, it is heated by the blind layer, the glazing layers, and the PV panel. This BIPV/T system is especially attractive because it can produce electricity and thermal energy in the form of preheated fresh air and allow for adjustable daylighting. There is a need to understand, design, and optimize BIPV/T systems. The velocity and temperature fields around the blind slats were experimentally and numerically studied. Experimental observations and numerical models are essential in understanding the complex fluid dynamical and thermal system and providing design and optimization guidelines. Solar-optical and Computational Fluid Dynamics (CFD) models were developed and validated at various blind slat angles and flow mean speeds. Particle Image Velocimetry (PIV) and temperature measurements were taken inside the ventilated facade. A simple empirical one-dimensional (1–D) model was developed, based on average surface temperatures and heat transfer coefficients, to quickly calculate average surface temperatures and heat flux rates. Between-the-panes convective heat transfer coefficients were obtained from CFD and used in the 1–D model. Despite high vertical temperature stratifications along the glazing, shading, and air layers, the 1–D model can predict the surface temperatures accurately and allow for future optimization and inclusion in building energy simulation software.

La Biomimicry è una scienza applicata che studia le forme, i materiali, i sistemi e i processi naturali per individuare soluzioni applicabili anche a problemi umani. Tale scienza trova applicazione in molti campi, quali l’agricoltura, la medicina, l’ingegneria e l’architettura. Grazie ai progressi compiuti nella modellazione parametrica, ad oggi sono disponibili potenti strumenti che, oltre alla simulazione energetica, consentono di esplorare le potenzialità delle soluzioni tratte dal mondo naturale nella progettazione architettonica, superando i limiti della semplice imitazione della forma. Una delle maggiori sfide per gli architetti negli ultimi anni è la riduzione della domanda energetica del costruito. Per i climi caldi, le esigenze di ventilazione e raffrescamento sono pertanto fattori cruciali per migliorarne la prestazione energetica. La tesi di ricerca affronta il problema della progettazione e dell’efficienza energetica dell’involucro edilizio in contesti climatici caldi, quale l’Egitto. A tal fine, è stato definito e applicato un approccio progettuale biomimetico-computazionale, per studiare e analizzare i comportamenti adattivi di termoregolazione di vari organismi naturali. In particolare, il lavoro di ricerca esplora possibili soluzioni architettoniche, ispirate a caratteristiche biologiche, per l’involucro di un edificio per uffici, con l’obiettivo di ridurre la domanda energetica per il raffrescamento. L’involucro dell’edificio è stato modellato parametricamente utilizzando Grasshopper Visual Programming Language per Rhino 3D Modeller, applicando inoltre alcuni algoritmi evolutivi multi-obiettivo per ottimizzare la soluzione architettonica rispetto al duplice obiettivo di diminuire i carichi di raffrescamento e mantenere un buon livello di illuminazione naturale. In tal modo, la riduzione dei carichi di raffreddamento non comporta un incremento dei consumi elettrici per l'illuminazione artificiale. Le prestazioni termiche dell’edificio sono state valutate con il software EnergyPlus. La soluzione architettonica esplorata è una facciata a doppia pelle ispirata a vari principi della natura. Le prestazioni della soluzione proposta sono state confrontate con quelle di un edificio per uffici esistente a Il Cairo. Il modello dell’edificio è stato ricostruito sulla base di planimetrie e specifiche sui materiali presenti; inoltre la disponibilità di dati sui consumi energetici per il raffrescamento dell’edificio ha permesso di valutare l’accuratezza della prestazione energetica calcolata con il software di modellazione. La soluzione progettuale è stata comparate anche rispetto alle prestazioni di una tipica facciata a doppia pelle. Inoltre le prestazioni termiche calcolate con EnergyPlus sono state confrontate con quelle ottenute con software di simulazione fluidodinamica computazionale (CFD), più accurati nel calcolo delle facciate a doppia pelle. Tale comparazione ha permesso di identificare il grado di errore e l’appropriatezza dell’uso di EnergyPlus nelle fasi iniziali della progettazione. La facciata a doppia pelle proposta consente una diminuzione della domanda di raffrescamento fino al 13,4%, migliorando al tempo stesso il livello di illuminazione naturale, che spesso costituisce uno dei maggiori limiti per l’applicazione di tale sistema. La ricerca termina con una sintesi dei risultati ottenuti e una valutazione complessiva del processo di progettazione presentato, degli strumenti di progettazione/simulazione utilizzati e delle prestazioni dell’involucro proposto, discutendone vantaggi e limiti. Sulla base delle sperimentazioni e dei risultati conseguiti, sono state individuate linee guida e raccomandazioni per la progettazione delle facciate a doppia pelle nei climi caldi. Inoltre viene fornita una matrice che raccoglie tutte le idee biomimetiche esplorate e analizzate, che rappresenta una mini-banca dati per architetti o designer interessati a questo approccio progettuale nell’affrontare i problemi di termoregolazione del costruito. Infine, la differenza di accuratezza tra i risultati di EnergyPlus e quelli dello strumento CFD è risultata trascurabile.
Biomimicry is an applied science that derives inspiration for solutions to human problems through the study of natural designs, materials, structures and processes. Many fields of study benefit from biomimetic inspirations, such as agriculture, medicine, engineering, and architecture. Technological advances in parametric and computational design software in addition to environmental simulation means offer very useful tools in order to explore the potential of nature’s inspirations in architectural designs that does not just mimic shapes and forms. Energy efficiency is one of the major and growing concerns facing architects. Cooling and ventilation needs are critical factors that affect energy efficiency especially in hot climates. This thesis addresses the problem of designing building skins that are energy efficient in the context of hot climates such as that in Egypt. The research attempts to define and apply a biomimetic-computational design approach to study and analyse natural organisms in terms of their behaviour regarding thermoregulation. Aiming to decrease cooling loads, the research explores possible architectural solutions for a biologically inspired skin system for office buildings. The building’s skin is parametrically designed using Grasshopper Visual Programming Language for Rhino 3D Modeller, and it is optimised using multi-objective evolutionary algorithms which are particularly important in the attempt of finding a range of solutions that reduce cooling loads while maintaining daylight needs. Consequently, the reduction in cooling loads should not be at the expense of increased energy consumption in artificial lighting. Simulations regarding the thermal performance were performed using EnergyPlus. A Double-Skin Façade (DSF) is proposed based on inspirations from nature. In order to evaluate the performance of the proposal, it is compared to the performance of the skin of an existing office building in Cairo acting as a reference case. Data regarding the reference case such as the building drawings, material specifications and annual cooling consumption were obtained in order to build its digital model and assess its accuracy. The proposed design is also evaluated by comparing it to a typical flat DSF. The obtained results regarding the thermal performance of the proposed building skin are verified by comparing them to results of more accurate simulations performed using Computational Fluid Dynamics (CFD). The aim is to know the degree of error as well as the appropriateness of using EnergyPlus for geometrically-complex DSFs in early design phases when CFD is not practical. The proposed DSF was able to decrease cooling loads by up to 13.4% while improving daylight performance at the same time which is often one of the main challenges of using DSFs. The research criticises the presented design approach as a whole, the design/simulation tools used and the performance of the proposed skin discussing their benefits and limitations. Based on the design experimentation and results, general guidelines and recommendations for DSF design in hot climates are presented. Additionally, the research presents a compiled matrix of the biomimetic ideas explored and analysed in order to serve as a mini-data bank for architects or designers interested in this design approach in addressing thermoregulation problems. Finally, the comparison between EnergyPlus and CFD software results showed minor differences.

博士
國立臺灣科技大學
建築系
94
In many studies of other countries about ecological construction, for the purpose of envelope load, ventilation, noise prevention, and specific visual penetrability, double-skin facades system that was actively developed by European countries at present, a construction research direction that has developed prosperously and popular trend are pointed out. However, the double-skin facades system is based on the natural environment of Europe, if the set pattern is followed in Taiwan, it may cause some unsuited or insufficient construction capabilities and negative results as a consequence. Based on the above, this study is to review and also try to raise the double-skin facades construction principle suitable for Taiwan aiming at local requirement and domestic climate, and furthermore, provide reference for decision making when Taiwan architecture related people implement double-skin facades system. A key point in this study is to compare the differences between original foreign theories and local influential factors, to build a basis for comparison and analysis of construction differences. The whole discussion process can be divided into three parts, first, it discusses related theories available, including function theories and construction theories available and foreign cases study; second, it investigates and analyzes domestic influential factors, including local restrictive conditions, investigation on the status quo of domestic construction available and also case study; and third, it builds the local constructional rules, including local boundary conditions and construction rules. According to the above discussion, this study makes the following conclusions. 1. The constructive characteristics box type double-skin facade: In Taiwan, additional facades does not give consideration to corresponding physical of functions. 2. The principles of active control: According to typical hot and wet weather in Taiwan and the environmental factor of sound, wind and light etc., double-skin facades system should apply active constructions system to reach the greatest efficacy. 3. Application of DSF to optimize natural ventilation in elementary school: Double-skin facades system should consider climate conditions for seasons'' change, cooperating with the switch of inner and outer skin opening and the use of second-hand air conditioner, to control the natural ventilation function driven by the heat insulation, sound insulation and thermal buoyancy of inner and outer facade. 4. Application of DSF to energy-savings within perimeter zone of office building: This study sets up a list of local construction rules that can be used by local architects and engineers to make strategic decisions according to different local conditions. 5. The application of old buildings skin renovation: Before the double-skin facades system is applied to renovation of residential building envelope, the combination equipment of air conditioner and skin structure must be put into consideration, and it is necessary to avoid the conflict between the heats exchange of air conditioner and the facilities for natural ventilation of the double-skin facades.

In order to mitigate the overheating problem in the warmer seasons, and thereby to improve thermal performance and energy efficiency of the Double-Skin Façade (DSF) system, this study introduced an innovative design approach involving the integration of thermal mass with the air channel of the conventional DSF. Then it proposed a numerical procedure to assess the thermal performance of DSF, and finally investigated the effect of thermal mass on the energy efficiency of such system. The initial step in the assessment procedure proposed the development of base-case models, which were able to predict temperature distribution in the DSF with a venetian blind. So too were the base-case models able to determine heating/cooling loads of the perimeter room for both the mechanically and naturally ventilated DSFs. In this procedure, building energy simulation software was used for base-case development; two distinct models were generated: an airflow model and a thermal model. The nodal, unidirectional airflow network method was applied in the case of the naturally ventilated DSF. The thermal model was a transient control volume method which found temperature distribution in discretized air-channel. The base-cases were verified at two levels: inter-model verification and verification relying on measurements from mechanically and naturally ventilated outdoor test-cells. At both levels, a generally fair agreement was obtained. After this, parametric studies pertaining to the energy performance of the system were conducted on the effect of thermal mass in unison with different air-channel configurations. Considerable energy load reductions were found when thermal mass was used in the air-channel, replacing venetian blind slats for mechanically ventilated DSFs; this held true during both summer and winter. In this configuration depending on the airflow path direction, energy savings from 21% to 26% in summer and from 41% to 59% in winter are achievable in compared with conventional DSF with aluminum venetian blind. The savings were found higher in sunny days than cloudy days. On the other hand, naturally ventilated DSFs combined with thermal mass were not found to be energy efficient in winter due to stack effect and airflow rate increase within the air channel

碩士
國立臺灣科技大學
建築系
90
Recently，the use of double-skin facades has gained increasing popularity in Europe and America for its better performance and securities. However，the hygrothermal climate in Taiwan，glass double-skin facades may not to be suitable for use. The aim of the thesis was to integrate ventilation, porosity and permeability of properties of external wall in local climate with double-skin facades，for achieving to improve indoor environment and reduce energy loads. This research evaluates the feasibility of using and the effects of improvement in indoor heat environment by means of compared full-scale experiments. The experimental porous material was perforated aluminum panel. A result of indoor heat environment was improved by installing porous in the outer façade of opening. Further, this study discussed the reduced effect of indoor heat environment factors. The better the reduced effect was, the less the porosity was. As porosity was the same, the reduced effect of less aperture（or more aperture numbers）was better than the bigger aperture. Using porous materials in the outer façade of opening，the reduce effect was for the most part of solar and thermal radiation. Therefore, utilizing porosity of porous materials evaluates the reduced effect of heat loads of opening. In terms of shading coefficient（ki） and reduced coefficient of heat loads were to act as estimate of indoor heat loads. Furthermore, the shading coefficient also was to act as design parameter of ENVLOAD.