Building Environmental Assessment Method Research Articles

Flow Inside a Recessed Space Outside a High-Rise Residential Building Due to Heat Rejection by One Air-Conditioner of Window-Type Per Story

Recessed spaces formed by the external walls at adjacent residential flats can be found outside many high-rise residential buildings in Hong Kong. During summer, a large number at window-type air-conditioners could be rejecting condenser heat into such a recessed space at the same time, when a powerful rising hot air stream is formed in this space. This paper describes the finding for recessed spaces at ‘I’ type for a 30-story building. Inside the recessed space, one Window-type air-conditioner is located per one story with its position that corresponds to the minimum dimensions prescribed by the HK-BEAM (Hong Kong Building Environmental Assessment Method) recipes. Prediction of the temperature and flow field in this space is performed by using FLUENT 5.0, a computational fluid dynamics (CFD) code. The development at detailed flow and temperature field inside the recessed space reveals existence at the hot ‘Γ’- shape bulk air stream together with one strong vortex pair. The mass flow rate and temperature at air inside the recessed space increases and entrainment of fresh air decreases with its height. For the highest condenser units at the inlet to the condenser cails, the temperature elevation at the air increases above 8°C, and its mass flow rate falls up to 40% below its nominal value. For the lowest units, this mass flow rate may be up to 12% higher than its nominal value.

Building environmental assessment methods: assessing construction practices

This paper focuses on the environmental issues associated with the building construction process and the way in which they are currently represented in building environmental assessment methods. The primary goal is to identify the practical and methodological reasons for their scant inclusion and to offer arguments to redress this situation. Despite the difficulties of assessing management practices, their inclusion within building environmental assessment methods is critical from the standpoint of reinforcing the relationship between building design and building operation. Similar arguments relate to the importance of including construction processes. The paper argues that construction issues should be included, organized into consistent categories (e.g. resource use, ecological loadings and health issues) and clearly partitioned within the structure of assessment methods. If there are environmental benefits in engaging a broader range of players earlier in the design process, then this notion can logically be extended to include the contractor.

Assessment of Envelope Energy Performance in HK-BEAM for Residential Buildings

The Hong Kong Building Environmental Assessment Method (HK-BEAM) is a voluntary scheme that aims to promote good practices that can minimise the adverse impacts of buildings on the environment. With the new 3/99 version launched in December 1999, HK-BEAM now covers also high-rise residentiai buildings. The scheme uses the overall thermal transfer value (OTTV) to assess the thermal peiformance of residential building designs because the caoling load In residential buildings is predominantly “skin-controlled”. Due to the largely different frequency and pattern Of use Of air-canditioning between residential units and commercial or hotel buildings, a new OTTV calculation method has been established. The paper presents the OTTV equation, the method used to generate the data required in the calculation and the correlation Of the OTTV with electricity consumption for air-conditioning In residential buildings. Apartfrom the values Of the weather dependent parameters to be used In the calculatian, the proposed met...

Building environmental assessment methods: applications and development trends

The construction and property sector has seen the development of a number of methods for evaluating the ‘greenness’ of buildings in the 1990s - both for new designs and existing buildings. These range from very detailed life cycle assessment methods, which account for all the embodied and operational environmental impacts of building materials, to higher level environmental impact assessment methods, which evaluate the broader implications of the building's impact on the environment. In between these two are environmental assessment methods such as BREEAM, BEPAC, LEED, and GBA. In this paper, we discuss the potential market applications of these systems and compare and contrast several of the major environmental assessment methods. Le secteur de la construction et de l'immobilier a été le témoin du développement d'un certain nombre de méthodes permettant d'évaluer les performances écologiques des bâtiments dans les années 1990, tant sur le plan des nouveaux concepts que des bâtiments existants. Ces méthodes vont de l'évaluation très détailée du cycle de vie, qui tient compte de l'impact spécifique et des incidences opérationnelles des matériaux de construction sur l'environnement, jusqu'à une évaluation de l'impact environnemental à un niveau plus élevé. Entre ces deux extrêmes, on trouve des méthodes d'évaluation environnementale telles que BREEAM, BEPAC, LEED et GBA. Dans cet article, nous examinons les applications commerciales potentielles des ces systèmes; nous comparons, en les opposant, plusieurs méthodes majeures d'évaluation environnementale.

Building environmental assessment methods: clarifying intentions

The intentions for, and the thinking behind, the Green Building Challenge (GBC) assessment framework and its development are made explicit. This paper disentangles three separate roles for environmental assessment of buildings (stimulating owners to improve a building's performance, informing decision makers during the design stages and delivering objective measurements of a building's impact on natural systems). The author provides a number of significant lessons from the development exercise and discusses further implications and directions for developing environmental assessment methods for buildings. A distinction is made between ‘green’ and ‘sustainable’ agendas and their implications for the future development of building environmental assessment methods. This is essential in order to clarify the many roles and applications demanded of these tools. The considerable practical overlap between the ‘green’ and ‘sustainable’ agendas suggests that they can be reconciled within a single tool. ‘Green’ performance is most usefully described in relative terms in comparison to similar buildings in the region, while absolute energy and mass flows are a prerequisite for assessing progress towards sustainability. A fewer number of carefully elected performance measures are required to provide a measure of a building's role in ecological sustainability than to describe its green performance. The GBC process has clarified the roles and applications demanded of different tools and these lessons will be integrated into the restructuring and application of GBTool, and add significantly to the wider debate on environmental assessment. Cet article explique les objectifs et les raisons qui ont amené à élaborer le cadre d'évaluation Green Building Challenge (GBC) ainsi que son évolution. Il précise le rôle de trois facteurs distincts qui participent à l'évaluation environnementale des bâtiments: inciter les propriétaires à améliorer les performances des bâtiments, informer les décideurs pendant la conception et fournir des mesures objectives de l'incidence d'un bâtiment sur les systèmes naturels. L'auteur tire un certain nombre d'enseignements significatifs de cet exercice et examine d'autres implications ainsi que des orientations relatives à l'élaboration d'autres methodes d'evaluation environnementale des bâtiments. Il fait la distinction entre les aspects ‘verts’ et les aspects ‘durables’ et examine leurs implications dans la perspective de l'elaboration de nouvelles méthodes. Cela est essentiel si l'on veut expliciter les nombreux rôles et applications demandés a ces outils. Cette distinction est capitale; le chavauchement considérable de ces aspects suggère que l'on pourrait les fusionner dans un seul outil. Les performances ‘vertes’ sont très bien décrites en termes relatifs, par comparaison à des bâtiments similaires de la région, alors que l'énergie absolue et les flux de masses sont une condition préalable à l'evaluation du progrès vers la durabilité. Un nombre moins important de mesures de performances sélectionnées avec soin servira à donner la mesure du rôle des bâtiments dans un contexte de durabilité écologique plutôt que de décrire leurs performances ‘vertes’. Le processus GBC a précisé les roles et les applications des différents outils et ces enseignements serent intégrés dans la restructuration du GBTool, de ses applications à une plus grande échelle et au débat élargi sur l'évaluation environnementale.

Lighting criteria in the Hong Kong Building Environmental Assessment Method

In the Hong Kong Building Environmental Assessment Method (HK-BEAM), lighting forms a significant part of the assessment. Assessment of lighting consists of two main itemS: energy consumption, and indoor lighting quality. The lighting criteria in HK-BEAM are described in this article. A model building is used for calculation, illustrating that buildings with higher credits in the lighting energy consumption assessment do contribute significantly more to energy savings. The model building is also used to demonstrate that the daylighting criteria in the current version of HK-BEAM are difficult to achieve. Sample assessment outcomes are also described and discussed.

Energy performance criteria in the Hong Kong building environmental assessment method

The Hong Kong Building Environmental Assessment Method (HK-BEAM), an environmental assessment method for air-conditioned office buildings, has been developed by the Real Estate Developers Association (REDA) for use in Hong Kong. Two versions of the scheme have been developed; one for new office premises and the other for existing office premises. HK-BEAM embraces a variety of issues related to the global, local and indoor environments. The efficient use of electricity forms a major part of the assessment. The basis for the energy performance assessment method, and the criteria for obtaining the relevant credits are described and discussed.

Emerging trends in building environmental assessment methods

The building environmental assessment field is reviewed since it first came into prominence in the early 1990s. Key limitations of existing building environmental assessment methods are identified and the emerging importance of issues such as sustainability, life-cycle assessment, globalization and standardization are discussed. The author provides a constructive direction for emerging ‘second generation’ building environmental assessment methods and protocols. This includes a standardization of environmental assessment methodologies; a common, generalized framework which allows for adaptation of specific and changing explicit criteria and an increased emphasis on building performance over time. Le champ d'estimation écologique du bâtiment est passé en revue depuis le début des années 1990, époque de sa première apparition remarquée. Les limitations-clés des méthodes d'estimation écologique des bâtiments existants sont identifiées, et l'importance manifeste de questions telles que viabilité, estimation de cycle de vie, mondialisation et standardisation est examinée. L'auteur offre une direction constructive de mise au point de méthodes et comptes-rendus d'estimation écologique de “seconde génération” naissante. Celle-ci comprend une standardisation des méthodologies d'estimation écologique, un cadre généralisé commun qui tient compte de l'adaptation de critères spécifiques variables explicites, ainsi qu'une importance accrue conférée aux performances des bâtiments dans le temps.

Noise Criteria for Hong Kong Building Environmental Assessment Method for New Offices and Existing Offices (HK-BEAM)

In response to the increasing awareness of environmental issues in relation to building projects, the building developers volunteered to develop a building environmental assessment method to self regulate the environmental impacts to the global, local and indoor environment of the buildings in Hong Kong (HK-BEAM [1,2]). This method does not intend to take the place of the conventional or functional criteria of design. The classical noise control criteria are reviewed. A set of assessment criteria is determined for the outdoor and indoor noise environment respectively, both during construction and post occupancy. This paper discusses the rational of the choice.

BECON: A Program for Predicting Building Energy Consumption for Air-Conditioning Buildings

An air-conditioning system simulation program BECON has been developed for predicting energy consumption for airconditioning in buildings. BECON relies on a buiiding heat transfer simulation pragram HTB2 to provide the input of hourly space cooling loads of a building. The two programs are adapted as the computing tool in HK-BEAM, the Hong Kong Building Environmental Assessment Method, launched in December 1996. in the paper, the range of system and equipment models included in BECON, the methods it uses to model the performance of air-conditioning systems, and the functions of its front-end program are described.