A knowledge-aid approach for designing high-performance buildings

Today, global warming and the sustained increase in energy prices have led to a quest for energy-efficient buildings among designers and users alike. This has been accompanied by increasingly strict thermal and energy regulations for buildings. In addition to such changes on the energy front, building regulations have also been created or reinforced in other areas, including accessibility, fire safety and seismic risk, alongside the demands of users. The combined effects of these two factors have made building design much more complex. Thus, designers are constantly in search of tools and information that can provide them with ways of designing high-performance buildings for their projects. In response to these needs, we propose an optimization-based, knowledge-aid approach for designing high-performance buildings. This approach is aimed at providing architects and design offices with clear knowledge of their project’s potential (exploration of various options) that will allow them to design the best possible high-performance buildings (in this version of the approach only energy needs and construction cost are assessed). This potential is evaluated by means of the external and internal geometric parameters as well as the energy characteristics of buildings. In this paper, the approach will be applied to an office building in Lyon, France.     

A comprehensive model for streamlining low-energy building design

Building designers are often limited in their ability to reduce the environmental impact of buildings, due to a lack of information on the environmental performance of building components as well as inconsistencies in the way in which this information is derived. Whilst numerous tools exist to help facilitate the low-energy building design process, these typically require large investments of time and money that are often beyond those available within any particular project. This paper describes an approach for streamlining the design process to reduce building life cycle energy consumption. Building assemblies are ranked based on an assessment of the life cycle energy requirements associated with their use within a building. This facilitates early stage assessment, negating the need for a resolved design before the relative energy requirements of alternate design solutions are known. Previous work assessed the initial and recurring embodied energy as well as the operational energy requirements for heating and cooling associated with the use of a range of building assemblies, using a simplified house model. This paper presents a sensitivity analysis of variations to the floor area, shape and orientation of this model, to test the reliability and applicability of the ranking approach across a broad range of circumstances. It was found that these variations did not influence the ranked order of the assemblies in terms of their life cycle energy requirements. Thus, the ranking of assemblies appears to provide an appropriate approach for streamlining the selection of construction elements during the building design process.     

Tools for quality control in simulation

This research examines the nature of environmental design information used by building designers. The goal is to identify commonality in the types of information that design tools should produce. It presumes that improving the use of design tools will lead to improved building performance. Through practitioner interviews, it investigates application of design decision support tools by building designers. It proposes a means of increasing designers’ use of these tools. This proposal derives from observation that systematic quality assurance (QA) systems are seldom used with simulation-based tools. The proposal is a QA system comprising (a) a simulation veracity test akin to the Turing test of computer intelligence; (b) an internet database of building performance information; (c) post-analysis tools that define the reliability of design tool output.     

Comparison of HVAC system modeling in EnergyPlus, DeST and DOE-2.1E

Building energy modeling programs (BEMPs) are effective tools for evaluating the energy savings potential of building technologies and optimizing building design. However, large discrepancies in simulated results from different BEMPs have raised wide concern. Therefore, it is strongly needed to identify, understand, and quantify the main elements that contribute towards the discrepancies in simulation results. ASHRAE Standard 140 provides methods and test cases for building thermal load simulations. This article describes a new process with various methods to look inside and outside the HVAC models of three BEMPs—EnergyPlus, DeST, and DOE-2.1E—and compare them in depth to ascertain their similarities and differences. The article summarizes methodologies, processes, and the main modeling assumptions of the three BEMPs in HVAC calculations. Test cases of energy models are designed to capture and analyze the calculation process in detail. The main findings are: (1) the three BEMPs are capable of simulating conventional HVAC systems, (2) matching user inputs is key to reducing discrepancies in simulation results, (3) different HVAC models can be used and sometimes there is no way to directly map between them, and (4) different HVAC control strategies are often used in different BEMPs, which is a driving factor of some major discrepancies in simulation results from various BEMPs. The findings of this article shed some light on how to compare HVAC calculations and how to control key factors in order to obtain consistent results from various BEMPs. This directly serves building energy modelers and policy makers in selecting BEMPs for building design, retrofit, code development, code compliance, and performance ratings.     

Effort and effectiveness considerations in computational design evaluation: a case study

Computational building evaluation tools have the potential to provide an effective means to support informed design decision making. Computational modeling, however, comes with a cost. Thereby, the most important cost factor is not software acquisition, but the time needed for learning and using the software. The extent of required time and effort is believed to be one of the main hindrances toward the pervasive use of computational building performance assessment tools by designers: Currently, modeling applications are mostly used, if at all, in the later stages of design and by specialists, rather than architects. However, few studies have explicitly dealt with the ascertainment and quantification of the actual effort needed to understand, master, and apply computational building evaluation tools. Thus, little factual information is available as to the cost and burden of computational building evaluation and its effectiveness in building design support. In this context, the present paper describes a case study, whose motivation was to estimate the time and effort needed by novice designers to computationally evaluate the performance of building designs. A group of senior architecture students participated in the study, learning and using a software application to assess the energy performance of six project submissions for a school building design competition. The outcome of this study (time investment ranges for various components of the modeling activity) was evaluated and further extrapolated to estimate the effort needed for a more comprehensive computational assessment of the environmental performance of these designs.     

Findings from a survey on the current use of daylight simulations in building design

This paper presents findings from a web-based survey on the current use of daylight simulations in building design. The survey was administered from December 2nd 2003 to January 19th 2004. One hundred and eighty five individuals from 27 countries completed the survey. The majority of respondents worked in Canada (20%), the United States (20%), and Germany (12%). Most participants were recruited through building simulation mailing lists. Their self-reported professions ranged from energy consultants and engineers (38%) to architects and lighting designers (31%) as well as researchers (23%). They worked predominantly on large and small offices and schools.Ninety one percent of respondents included daylighting aspects in their building design. Those who did not consider daylighting blamed lack of information and unwillingness of clients to pay for this extra service. Among those participants who were considering daylighting 79% used computer simulations. This strong sample bias towards computer simulations reflects that many participants had been recruited through building simulation mailing lists. Participants named tools’ complexity and insufficient program documentation as weaknesses of existing programs. Self-training was the most common training method for daylight simulation tools. Tool usage was significantly higher during design development than during schematic design. Most survey participants used daylighting software for parameter studies and presented the results to their clients as a basis for design decisions.While daylight factor and interior illuminances were the most commonly calculated simulation outputs, shading type and control were the most common design aspects influenced by a daylighting analysis. The use of scale model measurements had rapidly fallen compared to a 1994 survey, whereas, trust in the reliability of daylighting tools has risen. While participants named a total of 42 different daylight simulation programs that they routinely used, over 50% of program selections were for tools that use the RADIANCE simulation engine, revealing the program's predominance within the daylight simulation community.     

Shared conceptual model for the building envelope design process

The lack of communication and co-ordination among designers during the building envelope design process results in sub-optimal solutions leading to inadequate performance. To reverse this trend and to achieve better performance of the building envelope, professionals must be provided with computer integrated design tools which facilitate communication between participants and improve the transfer of data throughout the design process. This article presents a shared conceptual model that would enable integration in the building envelope design process. The wealth of data is organized into major envelope entities which are then decomposed into cohesive sets of data called primitives to form the conceptual model. Such a conceptual model should facilitate data exchange between design tasks, improve communications among designers and support the growth of data as the design process unfolds. The resulting conceptual model is implemented as a shared central database in an object-oriented database management system to experiment with integration.     

COMBINE: The HVAC-design prototype

Integrated intelligent building design systems (IIBDSs) are computer-based design environments which will in the future be used by engineers and architects to assist them in the design of buildings. This paper deals with the class of IIBDSs whose aim it is to improve the energy efficiency and overall performance of buildings. Development of these IIBDSs is a substantial task and may take some time to be realized. The EC COMBINE project and the U.S. AEDOT project have been initiated to take the first step towards developing these future IIBDSs. This paper focuses on the COMBINE project.

COMBINE's first step towards developing IIBDSs is to implement a building product model based on the ‘product modelling’ approach promoted by the computer-integrated manufacturing (CIM) community. This building product model allows information about a building to be passed between different design professionals (e.g. architects, heating, ventilating, and air-conditioning (HVAC) system designers etc.). Data exchange through the product model is tested using various design prototypes one of which is called the HVAC-Design prototype. The HVAC-Design prototype helps a HVAC system designer to select a preliminary HVAC system for a building.

This paper reviews: (a) ongoing research into the development of IIBDSs and (b) various software tools which may be incorporated into future IIBDSs. The main emphasis of the paper is on the COMBINE project and the functionality of the HVAC-Design prototype in COMBINE. There is also a discussion on how HVAC-Design may develop in the future.     

Geometry-based graphical methods for solar control in architecture: A digital framework

The form of a building is among the most critical design aspects concerning building energy consumption. Form-based passive design strategies, like solar control, can significantly reduce heating and cooling demands if implemented early in the design process. In this sense, there is an evident need for tools that can adequately support designers in their decisions. This paper aims to illustrate how geometry-based graphical methods (GGM) can provide effective support in the conceptual design stage. The paper introduces a novel digital framework for designing and analysing shading devices that leverages geometrical models and graphical methods. The digital implementation of GGM allows extending their applicability to three-dimensional and non-planar geometries. A comprehensive review of existing methods and tools for the design of shading devices lays the ground for the proposed digital framework, which is then demonstrated through two case studies. The results show that the diagrammatic nature of GGM facilitates a better and more direct understanding of the relationship between form and performance.     

Method and simulation program informed decisions in the early stages of building design

The early stages of building design include a number of decisions which have a strong influence on the performance of the building throughout the rest of the process. It is therefore important that designers are aware of the consequences of these design decisions. This paper presents a method for making informed decisions in the early stages of building design to fulfil performance requirements with regard to energy consumption and indoor environment. The method is operationalised in a program that utilises a simple simulation program to make performance predictions of user-defined parameter variations. The program then presents the output in a way that enables designers to make informed decisions. The method and the program reduce the need for design iterations, reducing time consumption and construction costs, to obtain the intended energy performance and indoor environment.     

Integrating building information modelling with sustainability to design building projects at the conceptual stage

Lately the construction industry has become more interested in designing and constructing environmentally friendly buildings (e.g. sustainable buildings) that can provide both high performance and monetary savings. In general, sustainability integrates the following three related components: (1) environmental, (2) economic, (3) social well-being. Incorporating these components at the conceptual stage is achieved by using sustainable design, through which designers must identify associated materials and systems based on any selected certification (rating) system. The use of building information modelling (BIM) concepts helps engineers design digital models that allow owners to visualize the building before the physical implementation takes place. To apply BIM concepts, designers use tools to create 3D models of buildings where the design materials and systems are selected from the built-in database of these tools. Designers will not be able to quantify the environmental impacts of these materials to support the decisions needed to design sustainable buildings due to the following reasons: (1) a lack of information about the sustainable materials that are stored in the database, (2) a lack of interoperability between the design and analysis tools that enable full life cycle assessments (LCAs) of buildings. This paper presents a methodology that integrates BIM and LCA tools with a database for designing sustainable building projects. The methodology describes the development and implementation of a model that incorporates a database in which information about sustainable materials is stored and linked to a BIM (3D) module along with an LCA module and a certification and cost module. The goal of this model is to simplify the process of creating sustainable designs and to evaluate the environmental impacts (EI) of newly designed buildings at the conceptual stage of their life. An actual building project is presented in order to illustrate the usefulness and capabilities of the developed model.     

A new approach to performance-based building design exploration using linear inverse modeling

Despite the development of a large number of building performance simulation tools, designers still need a systematic framework appropriate for energy-oriented decision-making in the early stages of design. While the current workflow follows a “forward” modelling procedure in which simulation tools predict the performance of a design, this study proposes an “inverse” procedure that entails a performance objective that estimates design parameters. Using linear inverse modelling, this approach generates plausible ranges for design parameters given a preferred thermal performance. The paper begins by demonstrating that thermal demand in a particular building operation-and-climate condition can be expressed as a linear regression model and then, in two case-studies, uses the regression model to develop an inverse algorithm. After defining energy performance targets as input, users obtain a probabilistic estimate of design parameters as output that represents a large “menu” of feasible design solutions, provides confidence, and embodies the iterative nature of design.     

Framework for capacity based sustainable design & development: towards resilient communities

The most fundamental struggle for realizing a sustainable built environment still lies in the use of non-renewable resources in its articulation. Although efforts have been taken to increase the use of sustainable materials the vast majority of the building sector still relies heavily on depletable resources. This article debates that the most fundamental contributors to sustainable development are the evaluation and incorporation of inhabitant capacities. Evaluating the available natural materials, inhabitant skills and tools could play a fundamental role in creating sustainable solutions. However, inhabitant capacity-models insufficiently cover all instrumental capacities into one model (both inhabitant and community). Therefore, this article describes: a framework for evaluating inhabitant capacities; how to map available resource capacities; how these capacities can be incorporated into sustainable housing development and planning. The framework was developed as a part of a support tool, which helps designers and engineers to evaluate inhabitant capacities. To describe the framework and support tool a rural Sub-Saharan community is used, as their capacities are relatively less complicated compared to a ‘western’ context. The article concludes that the framework shows great potential in reducing the use of unsustainable materials. Furthermore, that it could enable social sustainability by creating self-reliant and resilient communities.     

Semantic material name matching system for building energy analysis

As an importance of saving energy in building sector and reducing greenhouse gas emissions is rapidly growing, many tools for building energy analysis (BEA) have been developed. However, such tools still have much room for improvement: manual input of thermal properties of a building material; input of incorrect data; and semantic conflicts between building designers and engineers. This research proposes a semantic material name matching system to find a standardized material name and its associated material property values, and enter them into a BEA tool. The core of our approach is to define ontologies capturing the concepts associated with the standard materials and their property values that are required by BEA tools. The proposed system uses an IFCXML file of a building information model as a source of input data, captures material data in the files, and automates the process of material property input. Using the proposed system, engineers will be able to increase their efficiency in entering required data into BEA tools and to reduce the possibility of erroneous data input.     

Computer-aided building energy analysis techniques

Buildings are slowly replacing long-term investments that consume a lot of energy. Given current economic, as well as environmental constraints on energy resources, the energy issue plays an important role in the design and operation of buildings. Careful long-term decisions in the design and operation of buildings can significantly improve their thermal performance and thus reduce their consumption of energy. Alternative building design strategies, standards compliance and economic optimization can be evaluated using available energy analysis techniques. These range from simplified manual energy analysis methods for approximate energy use estimates to detailed computerized hourly simulation. The availability and ease of use of today’s computers make them effective tools in the decision-making process of building design. This paper reviews the most common building energy analysis techniques and the potential applications of computer technology in the energy simulation and optimization of buildings.     

Designing energy efficient commercial buildings—A systems framework

This paper provides a means for improving the effectiveness of energy related decision-making during the design phase of a building. A review of the literature and discussions with experts revealed that several approaches for an Integrated Design Process for energy efficient buildings exist. However, most of these approaches are relatively abstract and philosophical in nature, and do not prescribe procedures that enable energy efficient design.This paper attempts to address this gap by proposing a comprehensive design process titled the ‘Integrated Energy-Efficient Building Design Process’ (IEBDP). This process provides a framework based on systems theory that facilitates the integration of various facets of the energy-efficient alternatives selection process. In addition, the proposed framework seeks to integrate state-of-the-art analysis tools and methods, to aid designers in performing holistic building design. Analytical Hierarchy Process (AHP), a multi-attribute decision-making technique is used to resolve conflicts amongst diverging design goals.The proposed IEBDP framework was then used to design an office building, taken as a case study, in the composite climate of New Delhi, India. It was found that considerable energy savings could be achieved by following the IEBDP process. The benefits of this framework vis-a-vis traditional energy efficient design approaches were evaluated by comparing the design done through the IEBDP process with designs submitted by a group of practicing architects. The various designs were evaluated in terms of strategies adopted, the level of exploration as well as design integration, in order to validate the applicability and use of the IEBDP framework.     

Adapting cellular automata to support the architectural design process

This paper investigates the support of generative architectural design processes using cellular automata systems with a high level of involvement of human designers. Previous applications of cellular automata to architectural design have oftentimes been characterised by their limited generative capacity for top–down developmental control and for pragmatic rule-breaking as they are easily offered by human designers. This paper explores different options for modifying and extending classical cellular automata systems to support architectural form finding. It discusses the potential of cellular automata as generative design tools with respect to the questions: In which part of a design development, during which periods during a design process and in what roles do cellular automata promise desirable results from a practical standpoint? In response to these questions, a theoretical framework for the integration of cellular automata into the design process is presented. An implementation of a dialogue-based cellular automata-supported design process model is outlined and evaluated by remodelling an existing architectural design project.     

Analysis of an energy efficient building design through data mining approach

Incorporating energy efficiency and sustainable green design features into new/existing buildings has become a top priority in recent years for building owners, designers, contractors, and facility managers. This paper intends to address why delivery of an energy efficient building is not just the result of applying one or more isolated technologies. Rather, it can best be obtained using an integrated whole building process throughout the entire project development process, which leads building designers to generate a large amount of data during energy simulations. The authors observed that even a simple energy modeling run generated pages of data with many different variables. The volumes of energy modeling data clearly overwhelm traditional data analysis methods such as spreadsheets and ad-hoc queries with so many factors to be considered. An integrated or whole building design process involves studies of the energy-related impacts and interactions of all building components, including the building location, envelope (walls, windows, doors, and roof), heating, ventilation and air conditioning (HVAC) system, lighting, controls, and equipment, which shows why it is so difficult to find the correlation between different systems. The objective of this research is to develop an energy efficient building design process using data mining technology which can help project teams discover important patterns to improve the building design. This paper utilizes the data mining technology to extract interrelationships and patterns of interest from a large dataset. Case study revealed that data mining based energy modeling help project teams discover useful patterns to improve the energy efficiency of building design during the design phase. The method developed during this research could be used to guide designers and engineers through the process of completing an early design energy analysis based on energy simulation models.     

天津市太阳能建筑发展情况探析

本文以天津市太阳能建筑的发展现状为切入点,结合实际工程项目,分析、比较各项目的优缺点,研究太阳能建筑在城市中的发展情况与遇到的问题,以期找到太阳能建筑在城市中发展的动力和潜力。研究结果表明,太阳能建筑在天津市发展情况并不乐观,各种因素束缚了太阳能建筑在大城市的发展。目前,推动太阳能建筑发展的一个关键因素是太阳能与建筑的一体化设计和建造．这对政府、开发者及设计施工人员都提出了新的要求。     

Evaluation of BIM energy performance and CO2 emissions assessment tools: a case study in warm weather

ABSTRACT

The EU members have adopted regulations and official methods for evaluating the energy performance in buildings. Most of these methods are applied at the end of the project phase, with few opportunities to correct erroneous design decisions when the desired building energy performance is not achieved. It is demonstrated that there is no European standard for sustainability and that the decision-making process during the development of a building project is compromised by the methodologies and some concepts, as thermal inertia, are withdrawn. Currently, the industry has been developing alternative tools for evaluating energy performance and CO₂ emissions in buildings over their entire life cycle. These software programs, which belong to the BIM environment, use databases and make simplifications adapted to the stage of design when the software can be applied. The main objective of this paper is to evaluate the accuracy of this software and how the databases and simplifications influence the decision-making process in building design. Calculation examples are carried out with various tools and compared to real building performance data. The results demonstrate that, as with the official methods, the tools influence the results and therefore condition, sometimes wrongly, the decision-making process to produce better buildings.