CONCEPTUAL: An Expert System for Conceptual Structural Design

In the conceptual design stage of a building the number of possible building configurations is enormous. The building systems selected in this stage affect the building cost much more than any other decision made in the subsequent design stages. Currently designers base their decisions mostly on experience and intuition. Since this process is not algorithmic, the best possible design is not guaranteed. In this article a model of the process by which a human expert arrives at a conceptual design for a building is presented. Based on this model, CONCEPTUAL, an automated knowledge-based expert system has been developed by the authors to aid in the conceptual design stage of buildings.     

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.     

Life-cycle cost analysis and life-cycle assessment of the second-generation benchmark building subject to typhoon wind loads in Hong Kong

Tall buildings located in Hong Kong can suffer great damage caused by typhoon hazards throughout their lifetimes. In addition, the effect of wind hazards may be exacerbated due to increases in the typhoon intensity and frequency caused by the climate change effect. Therefore, developing a framework to evaluate and quantify the damage caused by wind hazards on tall buildings from the economic perspective is critical for engineers and building owners in designing a cost-effective tall building. In this study, an economic damage indicator, life-cycle cost, is measured by using a probabilistic method called life-cycle cost analysis (LCCA). Moreover, the building sector is one of the biggest contributors to greenhouse gas (GHG) emissions, and the environmental impact that may be generated in intervention activities after wind-induced damage occurs is analyzed. An environmental impact indicator, embodied carbon emission, is quantified by employing another probabilistic method called life-cycle assessment (LCA). Therefore, an integrated methodology combining the LCCA and LCA is proposed to evaluate potential damage costs and environmental impact caused by typhoon hazards on tall buildings.     

住宅建筑气候适应性优化设计研究

以中国5个典型城市的气候条件为例，提出住宅建筑气候适应性优化设计流程。基于Grasshopper参数化性能分析平台，和Ladybug/Honeybee环境分析插件，以热环境舒适度模型、建筑能耗模型和建筑生命周期成本模型为目标函数进行优化分析。发现哈尔滨和北京气候条件下，住宅建筑应选择nZEB'（权衡最优）设计参数，而上海、昆明和深圳气候条件下，C-O（成本效益最优）解决方案比nZEB（节能最优）解决方案的综合效益更好。基于参数化性能模拟的多目标优化可以有效辅助住宅建筑的气候适应性设计研究。     

Integration of fire safety and building design

A new framework is presented to facilitate better incorporation of building fire safety performance options into the building design process. Based on the building design process and key design decisions undertaken at each phase, a knowledge set is developed to aid building designers to understand better the effects of design decisions on building fire performance. This also minimizes potential competing objectives in later design phases by sharing necessary concerns in advance. Drawing on the knowledge set, a conceptual building fire safety evaluation tool illustrates how primary building designers and fire safety engineers can quantitatively assess fire safety performance for different solutions. It is shown how building fire safety performance attributes can be arranged by building design phase, how various scenarios can be explored, and how appropriately balanced building design and fire safety design solutions can be identified at different phases of the building design process.     

Applying multi-objective genetic algorithms in green building design optimization

Since buildings have considerable impacts on the environment, it has become necessary to pay more attention to environmental performance in building design. However, it is a difficult task to find better design alternatives satisfying several conflicting criteria, especially, economical and environmental performance. This paper presents a multi-objective optimization model that could assist designers in green building design. Variables in the model include those parameters that are usually determined at the conceptual design stage and that have critical influence on building performance. Life cycle analysis methodology is employed to evaluate design alternatives for both economical and environmental criteria. Life cycle environmental impacts are evaluated in terms of expanded cumulative exergy consumption, which is the sum of exergy consumption due to resource inputs and abatement exergy required to recover the negative impacts due to waste emissions. A multi-objective genetic algorithm is employed to find optimal solutions. A case study is presented and the effectiveness of the approach is demonstrated for identifying a number of Pareto optimal solutions for green building design.     

The application of building performance simulation in the writing of architectural history: Analysing climatic design in 1960s Israel

This article presents a methodology for the integration of building performance simulation (BPS) into the writing of architectural history. While BPS tools have been developed mainly for design purposes, their current maturity enables to reliably apply them in simulating the performance of past buildings, even when these buildings have been significantly modified or demolished. The possibility to virtually reconstruct the performance of past buildings can help us to overcome the existing knowledge gap in the understanding of the role played by building performance and building performance research through the history of architecture and can therefore promote the intelligent and successful application of environmental features in contemporary architecture. The potential of the proposed methodology is presented here using a historical case study from 1960s Israel (a university building in Tel Aviv), in which climatic considerations were anexplicit part of the entire design process. The original thermal performance of the building was analysed by employing the EnergyPlus simulation engine, and the simulation results were used for evaluating the climatic impact of certain design decisions, comparing them with the proclaimed design goals and the original intentions of the architects.     

A cost effective approach to design of energy efficient residential buildings

The objective of this study is to identify cost-optimal efficiency packages at several levels of building energy savings. A two-story residential building located in Jordan is selected as a case study. DesignBuilder software is used to predict the annual energy usage of a two-story residence in Irbid, Jordan. Real-time experimental data from a single isolated controlled room was used to verify the proposed model. In addition to energy analysis, the economic, environmental, and social benefits of the proposed design have been investigated. The sequential search optimization approach is used to estimate the minimum cost of the building while considering various design scenarios. In addition, the impact of various energy conservation techniques on residential buildings is assessed, and the payback period for each program is calculated. Ultimately, the optimal combination of design to achieve energy efficiency measures has been identified in several climate regions. The simulations results predict that the annual electricity consumption can be reduced up to 50% if the proper combinations of energy conservation measures are selected at the lowest cost. The payback period is 9.3 years. Finally, energy efficiency measures can lead to a total of 9470 jobs/year job opportunities.The study provide practical framework to link between energy performance criteria and economic goals of building. Linking the energy performance requirements to economic targets provides guidelines for homeowners, contractors, and policymakers for making a suitable decision regarding the retrofitting of existing residential buildings. The study focuses on developing new methodologies that support minimizing costs during a building's lifecycle while maximizing environmental benefits which can not be identified by a series of parametric analyses using individual energy-efficient measures.     

绿色建筑全寿命周期成本控制管理研究

本文对绿色建筑全寿命周期的影响因素进行了全面分析,探讨了绿色建筑全寿命周期成本控制管理的方法,提出了加强绿色建筑全寿命周期成本控制管理的政策建议,为全面推广绿色建筑全寿命周期成本控制管理奠定了基础。     

Life cycle cost implications of energy efficiency measures in new residential buildings

The importance of the built environment from an environmental impact and energy use perspective is well established. High thermal efficiency of the constructed building envelope is a key strategy in the design and construction of buildings which limit use of active space conditioning systems. Australia's current housing stock is thermally poor and national energy performance standards are relatively weak when benchmarked against international best practice. A lack of data has impeded the policy debate and a significant gap in analysis remains a lack of empirical research into the life-cycle cost implications of increased building thermal efficiency, particularly for residential buildings. This paper applies an integrated thermal modeling, life cycle costing approach to an extensive sample of dominant house designs to investigate life cycle costs in a cool temperate climate, Melbourne Victoria. Empirical analysis provides new insights into lifetime costs and environmental savings for volume housing design options and identifies sensitive factors. Results suggest that the most cost-effective building design is always more energy efficient than the current energy code requirements, for the full time-horizon considered. Findings have significant policy implications, particularly in view of present debates which frequently present higher energy efficiency standards as prohibitive from a costs perspective.     

Historical analysis of the economic life-cycle performance of public school buildings

ABSTRACT

Scientific community and practitioners of the Architecture, Engineering and Construction (AEC) sector have been developing life-cycle cost (LCC) concept for the past decades. However, information on a building’s economic performance throughout its life-cycle is seldom readily available or accurate. This hinders the fulfilment of recommendations of international and regional standards, procurement guidelines and regulations, and for building management (BM) professionals to fully incorporate the LCC concept into their daily practice. This paper seeks to contribute to solving these difficulties by presenting a conceptual framework that enables LCC-informed decisions in BM, together with its empirical application to a portfolio of 158 public school buildings in Portugal (constructed area of 1,437,594?m²). It involved the gathering, organization and treatment of historical data of school buildings originally constructed from 1942 onwards. The historical analysis is presented in the form of three types of economic life-cycle key performance indicators (time series, indexes and relative ratios). It originated a database with more than 1.4 million results that offer a profound understanding of historical economic performance of this portfolio. The results can be adapted and used to benchmark or estimate construction, operation, maintenance, repair, replacement, rehabilitation, energy consumption, water consumption and deconstruction costs of buildings throughout the world.     

A physical study of plumbing life cycle in apartment houses

We know that extending the life span of a building can reduce environmental impact, and also save money with the viewpoints of life-cycle cost. But due to the complex system construction of buildings, if we apply the concept of life-cycle cost to design, we must consider it in coordination with the life spans of subsystems in order to avoid unreasonable wastage and problems of utility function. Concerning corrosion of piping, past documents mostly direct investigation and analysis to the physical or chemical characteristics of materials. This paper focuses on the plumbing system of a building, by matching up the investigation of practical cases, we determined the life span of a plumbing system in a building and try to offer an assessment system for a life-cycle model. This could be of use in life-cycle architectural planning and design.     

Energy nomographs as a design tool for daylighting

The purpose of this paper is to inform commercial building designers about an energy analysis tool which can aid them in making appropriate decisions about daylighting. The energy nomographs are an energy design tool which calculate the annual energy consumption of commercial buildings, including lighting, heating, cooling, domestic hot water, fans, pumps, and miscellaneous items. This paper specifically discusses the daylighting aspects of the tool. The calculation procedure is presented with an example to explain how this design tool can be used to make good energy decision eearly in the design process.     

A performance assessment ontology for the environmental and energy management of buildings

Narrowing the performance deficit between design intent and the real-time environmental and energy performance of buildings is a complex and involved task, impacting on all building stakeholders. Buildings are designed, built and operated with increasingly complex technologies. Throughout their life-cycle, they produce vast quantities of data. However, many commercial buildings do not perform as originally intended.This paper presents a semantic web based approach to the performance gap problem, describing how heterogeneous building data sources can be transformed into semantically enriched information. A performance assessment ontology and performance framework (software tool) are introduced, which use this heterogeneous data as a service for a structured performance analysis. The demonstrator illustrates how heterogeneous data can be published semantically and then interpreted using a life-cycle performance framework approach.     

The anatomy of investing in energy efficient buildings

A building investment is a real decision because the allocated resources are typically irrevocable for long times. Investment appraisal is a logic method to process elapsing time, uncertain benefits and costs, and irrevocability related to decisions. Most analysts stop halfway the appraisal process when they carefully assess net present values and their sensitivity to uncertain future events. But sidelining irrevocability and the dynamic sequential analysis of future events and actions cause wrong decisions when the energy performance endowment of a new building is decided. Irrevocability and preclusion are explained, and their impact illustrated with a case study. Adopting realistic assumptions about the uncertain future and applying the proper methodology reveal as financially best choice the immediate investment in passive attributes and items. Irrevocability is of high relevance for building efficiency investments and for the implementation of the EU-2010 buildings directive.     

Towards a successful voluntary building environmental assessment scheme

Voluntary building assessment schemes have emerged worldwide to help assess the environmental performance of buildings. As building environmental assessment is a rapidly evolving field, the scope and details of such assessment schemes are continuously undergoing updating and refinement. Substantial efforts have been devoted to the design and improvement of the assessment schemes to make them capable of defining an objective building profile. Although most of the existing schemes are voluntary, many fail to encourage participation of the building investors and designers. In order to widen acceptance, the design of the scheme should be oriented towards the manner in which investors make decisions. This paper provides an overview of the vital elements and changes needed, so as to make a voluntary building environmental assessment scheme more attractive and successful, and will include reforms not only in the scope and the credit weighting philosophy but also in its nature.     

Beyond the code: Energy, carbon, and cost savings using conventional technologies

As states in the U.S. adopt new energy codes, it is important to understand the benefits for each state and its building owners. This paper estimates life-cycle energy savings, carbon emission reduction, and cost-effectiveness of conventional energy efficiency measures in new commercial buildings using an integrated design approach. Results are based on 8208 energy simulations for 12 prototypical buildings in 228 cities, with 3 building designs evaluated for each building-location combination. Results are represented by easy-to-understand mappings that allow for regional and state comparisons. The results show that the use of conventional energy efficiency technologies in an integrated design framework can decrease energy use by 15-20% on average in new commercial buildings, and over 35% for some building types and locations. These energy reductions can often be accomplished at negative incremental life-cycle costs and reduce a building's energy-related carbon footprint by 9-33%. However, generalizing these results on energy use, life-cycle costs, and carbon emissions misses exceptions in the results that show the importance of location-specific characteristics. Also, states do not appear to base energy code adoption decisions on either potential energy savings or life-cycle cost savings.     

Decision‐making in a model‐based design process

Decisions early in the design process have a big impact on the life cycle performance of a building. The outcome of a construction project can be improved if different design options can rapidly be analysed to assist the client and design team in making informed decisions in the design process. A model‐based design approach can facilitate the decision‐making process if the design alternatives' performances can be evaluated and compared. A decision‐making framework using a performance‐based design process in the early design phase is proposed. It is developed to support decision‐makers to take informed decisions regarding the life cycle performance of a building. A scenario is developed in order to demonstrate the proposed framework of evaluating the different design alternatives' energy performance. The framework is applicable to decision‐making in a structured design process, where design alternatives consisting of both objective and subjective evaluation criteria can be evaluated.     

Uncertainty-based life-cycle analysis of near-zero energy buildings for performance improvements

Near-zero energy buildings( nZEBs) are considered as an effective solution to mitigating CO_2 emissions and reducing the energy usage in the building sector. A proper sizing of the nZEB systems( e. g. HVAC systems,energy supply systems,energy storage systems, etc.) is essential for achieving the desired annual energy balance,thermal comfort,and grid independence. Two significant factors affecting the sizing of nZEB systems are the uncertainties confronted by the building usage condition and weather condition,and the degradation effects in nZEB system components. The former factor has been studied by many researchers; however,the impact of degradation is still neglected in most studies. Degradation is prevalent in energy components of nZEB and inevitably leads to the deterioration of nZEB life-cycle performance. As a result,neglecting the degradation effects may lead to a system design which can only achieve the desired performance at the beginning several years. This paper,therefore,proposes a life-cycle performance analysis( LCPA) method for investigating the impact of degradation on the longitudinal performance of the nZEBs. The method not only integrates the uncertainties in predicting building thermal load and weather condition,but also considers the degradation in the nZEB systems. Based on the proposed LCPA method,a two-stage method is proposed to improve the sizing of the nZEB systems.The study can improve the designers "understanding of the components"degradation impacts and the proposed method is effective in the life-cycle performance analysis and improvements of nZEBs. It is the first time that the impacts of degradation and uncertainties on nZEB LCP are analysed. Case studies showthat an nZEB might not fulfil its definition at all after some years due to component degradation,while the proposed two-stage design method can effectively alleviate this problem.     

Future proofing PPPs: Life-cycle performance measurement and Building Information Modelling

Public–private partnerships (PPPs) are widely used to procure public infrastructure assets and are an effective mechanism for ensuring value for money. However, many PPPs in Australia have been plagued with controversy as they have experienced significant cost and schedule overruns during construction. Critical to the successful delivery of PPP projects is effective performance measurement/evaluation. Yet, conventional ex-post evaluation that solely focuses on meeting budget and a predetermined schedule are invariably applied to measure PPPs in practice. This paper reviews the performance measurement literature used to evaluate PPP projects and proposes that a life-cycle approach to their evaluation is needed to ‘future proof’ their performance and ensure value for money that is delivered to the public sector. As the primary focus of PPPs is to maximise profitability, there is a need to ameliorate the coordination and integration between the Special Purpose Vehicle, end-users and the public sector. This can be enabled through the adoption of Building Information Modelling (BIM) as it not only provides digital representation of the physical and functional characteristics of an asset, but also provides key decision makers with the ability to make informed decisions across a project's life-cycle. When aligned with a series of core indicators that are used for performance measurement, it is suggested that BIM can act as a catalyst for ‘future proofing’ PPPs and enable the successful management of an asset throughout its life-cycle.