Michael Donn

Tools for quality control in simulation

Abstract 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.

Digital to Physical: Comparative Evaluation of Three Main CNC Fabrication Technologies Adopted for Physical Modelling in Architecture

The objective of this experimental study is to investigate and systematise data regarding the production issues and limitations of Computer Numerically Controlled fabrication technologies typically adopted for physical modelling in architecture. This study also aims to observe the value of potential feedback to the design process from different types of digitally fabricated architectural models. This experimental research systematically explores digital fabrication as a computer-aided modelling tool using two international architectural competition projects as case studies: the design of a skyscraper and relocatable schools. Developed by the authors especially for this research paper, each case study acts as a test bed to compare and evaluate digital production techniques adopted for physical modelling in architecture. Designs go through a process of refinement using CNC fabrication as an integral part of the design process. Each step in the process is closely evaluated as to its effectiveness according to a matrix of feedback criteria.

A Comparative Study in the Architectural Design of Low Energy Apartments For Two Climates: New Zealand and Reunion Island

This work is part of a global research project whose aim is to identify the principal design features of the zero energy apartment building. Its approach is to compare and contrast apartment designs for different climates. This paper deals with the comparison of apartment building design for New Zealand and Reunion Island. Both are influenced by the ocean and the altitude, but are at very different latitudes. Apartment design strategies are different for temperate climates and tropical climates, but in terms of low energy goals, some basic principles may be the same and can be applied anywhere in the world. If an apartment is well-designed and is well-adapted to its local climate, it is possible to apply the same design rules and standards for all apartments and both for temperate and tropical climates.

Energy — audit and management: Practical application of methodology in USE of energy audits in New Zealand schools

The authors, Nigel Isaacs, Michael Donn and Dr George Baird of the School of Architecture, Victoria University of Wellington, present a succinct account of the practical difficulties they encountered when implementing recommendations from energy audits in a defined number of New Zealand schools. It is concluded that these difficulties relate more to funding and personnel than the engineering of the energy savings in themselves.

Energy use and height in office buildings

ABSTRACT The relationship between energy use and height is examined for a sample of 611 office buildings in England and Wales using actual annual metered consumption of electricity and fossil fuels. The buildings are of different ages; they have different construction characteristics and methods of heating and ventilation; and they include both public and commercial offices. When rising from five storeys and below to 21 storeys and above, the mean intensity of electricity and fossil fuel use increases by 137% and 42% respectively, and mean carbon emissions are more than doubled. A multivariate regression model is used to interpret the contributions of building characteristics and other factors to this result. Air-conditioning is important, but a trend of increased energy use with height is also found in naturally ventilated buildings. Newer buildings are not in general more efficient: the intensity of electricity use is greater in offices built in recent decades, without a compensating decrease in fossil fuel use. The evidence suggests it is likely – although not proven – that much of the increase in energy use with height is due to the greater exposure of taller buildings to lower temperatures, stronger winds and more solar gains.

Some simple methods for reducing daylight simulation time

ABSTRACT A significant barrier to routine use of Climate-Based Daylight Modelling in early design is the long time that it takes to run full annual simulations. Quick checks of design ideas are thus inconvenient, which discourages examining large numbers of design options or doing routine sensitivity analysis. Two ways of reducing required simulation time are to not simulate all the daytime hours of the year, or to simulate far fewer grid ‘measurement’ points. This paper demonstrates the effectiveness of taking smaller samples of random days throughout the year to reduce simulation time. By using a selection process to select “representative” samples of hours, simulations using only 5 days/month provide results with <6% error in performance estimates – well within accepted tolerances. The paper also shows the insignificant difference in design information provided by oft-recommended dense sensor grids compared to a 5 × 3 or 10 × 5 grid across a room plan.

Looking in the Mirror: Can we Change the Reflection of our Residential Housing?

This paper reports the results of a set of serial interviews with home owners in New Zealand. Its aim was to examine how people currently make choices towards sustainable design measures so that we may better understand and market to the social factors influencing sustainable design and building within our cultures.

DEVELOPMENT OF PASSIVE SOLAR HEATING IN NEW ZEALAND

ABSTRACT This paper discusses the design priorities for passive solar buildings in New Zealand, the current status of development of passive solar technology, and an example of a New Zealand community that is actively embracing solar design as a component in their residential development planning.

The analysis of the factors affecting energy use in the commercial buildings of the Wellington CBD

This paper describes the methods used and the results obtained during a study of energy consumption in the commercial buildings of the Central Business District of Wellington, the capital city of New Zealand. Data was collected on the energy consumption, floor area and occupancy of 1,107 buildings, together with their design and operational characteristics. Analysis of the data demonstrated that both floor area and number of occupants provide useful bases for comparison of the intensity of energy use in buildings. Categorising premises within buildings into activity groups produced significantly different mean energy intensities for each activity. The factor most often associated with energy use for all activity groups, and apparently, therefore, the major determinant of energy use in these buildings, was the complexity and degree of centralisation of the HVAC services. The information derived from this data constitutes the most comprehensive picture yet produced for a major collection of New Zealands commercial buildings. It provides a basis for comparisons with other centres data and for the eventual production of a national data base.

Hvac Systems' Performance

The authors, from the Energy Research Group of the School of Architecture, Victoria University of Wellington, New Zealand, discuss energy-use surveys of 1107 commercial buildings in the central business district of Wellington and detailed monitoring of three of the buildings. The surveys showed that the more centralised the HVAC plant, the greater the energy use; architectural factors were t significant. The monitoring revealed that Energy Management and Control Systems have produced dramatic savings in heating energy consumption—but in all three buildings tenant electricity costs were greater than the total central heating costs. The paper continues our selection of presentations at the September 19S3 symposium in Stockholm by CID W17—Heating and climatisation.