Nigel Isaacs

Housing and health: The relationship between research and policy

There is a long tradition of using housing interventions to promote public health, despite causative factors being unclear. This article reviews the research evidence on the key aspects of poor housing such as inadequate maintenance, over crowding, low temperatures and dampness, that have been identified as contributing to the impact of housing on health. Possible intervening factors such as house dust mites and fungi are also reviewed. This evidence is discussed in the context of possible confounding factors such as housing location and tenure. Conclusions are drawn about the adequacy of the research evidence as a basis for changing building regulations and other policy measures as a way of improving health.

Understanding energy and the non-domestic building stock: in memory of Harry Bruhns

This special issue celebrates the career and research of Harry Bruhns (1951–2011). It includes papers by Bruhns’s colleagues and students, and by others who have been working on the subjects that occupied him. The contributors are from New Zealand (NZ) and the UK, the two countries where Bruhns lived and worked. The topics range widely, but the common theme is the nature and performance of the building stock, in particular the non-domestic stock and its use of energy, the focus of most of Bruhns’s research.

Time-use in different rooms of selected New Zealand houses and the influence of plan layout

House interiors are affected by outdoor and indoor pollutants although levels of exposure differ with room type. The times people spend in rooms also differ, and hence their potential level of exposure, which is the focus of this article. Additionally, time spent in a kitchen during cooking, which is the main source of indoor particulates for non-smoking households, could affect indoor air quality in other rooms, especially where the kitchen is part of an open plan arrangement. This study investigated the time people spend in all rooms including kitchens and open plan kitchen/dining/living in New Zealand houses. On average, New Zealanders spend 54% of time at home indoors in usual bedrooms and 29%–36% in a living room, dining room, and kitchen (or combination of these). People in open plan houses spend less time in living areas than those in cellular plan houses, but effectively more time in the ‘kitchen’. Given time spent in a combined living room/dining/kitchen, combined living room/kitchen or combined dining room/kitchen is effectively time spent in a kitchen, people spend respectively 3.23, 1.36 and 0.53 h/day more in the kitchen compared to those having a separate kitchen, which could increase their chance of exposure to kitchen pollutants.

Understanding the New Zealand non-domestic building stock

Unlike the residential building stock, most countries have poor information on their non-domestic stock. This necessitates the use of other data sources. In the mid-1980s the (then) New Zealand Department of Valuation digitized its valuation records. This permitted the first analysis of an entire countrys non-domestic buildings. A very long-tail probability density function was identified, with the largest 5% of buildings containing more than 40% of the floor space. This knowledge informed the development of research for understanding non-domestic buildings as well as underpinning the 1996 revision of the NZ Building Code Clause H1 Energy Efficiency. More recently an analysis of valuation data has provided the Building Energy End-use Study (BEES) with a national sampling frame to examine energy and water end-uses in non-domestic buildings. The development of processes for collecting and analyzing data is described. Considerable changes in understanding of valuation data have occurred for documenting the non-domestic building stock. New online and geographic information sources can validate and improve building data. The use of such a database supports improved understanding of the changing nature of the building stock and potential intervention points, as well as harnessing regulatory and market forces.

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.

The effect of global trade on the New Zealand house

This chapter explores the international origins of seven selected materials (cement; asbestos cement boards; window glass; corrugated iron; nails; fibrous plaster; roofing slates) and suggests it has never been possible to prepare a standardized analysis of the environmental impacts. Even something as apparently simple as the timber-framed house with a corrugated iron roof may use materials sourced locally, nationally, and internationally. Extraction of the raw material(s), processing into the appropriate product, transport from the manufacturing location to the site of use, and the construction into the completed building can each have a wide range of paths, leading to complexity and imprecision in undertaking a lifecycle analysis.

Finding Faults with Residential Buildings

Since 2004, Buildsure Associates has provided house inspection services, completing over 700 inspections. This chapter describes the inspection process and the methods used to communicate the results to the house owner. A random sample of 70 reports was taken and processed into a database which has been subject to statistical analysis. The large majority were for free-standing timber-framed houses with different claddings. 46 % of the houses had only suspended floors, 30 % only slab-on-grade, and the rest both floor types. Just one-fifth (21 %) of the houses could be considered to be in excellent condition. The full set of reports was also examined to select common problems, and these are discussed with appropriate site photographs. Given that when a house is being sold, the seller wishes to present it in the most positive light, this would suggest there is a very large, currently unmet, need for house maintenance work. Three common issues have been identified: asbestos (present in 36 % of reports), high moisture levels (35 % mean timber moisture levels of 14 % or above), and subfloor ventilation (53 % of the timber bearer moisture measurements were in the 16 % to over 22 % range). The identification of problems is a first step to their resolution. Future analysis of this database, along with other research exploring the condition of New Zealand houses, is being undertaken and will help to lead not only to improved durability of the houses but also create an improved environment for living.