14th December 2012, Volume 125 Number 1367

Michael G Baker, Philippa Howden-Chapman

The paper by Trenholme and colleagues in this issue of the Journal provides further evidence of the need to improve housing as a high priority for protecting the health of vulnerable children in New Zealand.1 This experienced group of researchers obtained information on 508 hospital admissions for lower respiratory tract infection in children aged less than 2 years in Counties Manukau from August to December 2007 (notably during a period of relatively low unemployment). They identified markedly higher hospitalisation rates for Māori and Pacific children and those living in the most deprived neighbourhoods.

Two-thirds of children were potentially exposed to secondhand tobacco smoke, 27% reported no source of heating at home and 33% lived with four or more children. A study of 106 child admissions to Wellington Hospital in August 2012 identified a similar pattern of high rates of respiratory admissions in Māori and Pacific children and a strong association with poor housing conditions.2

The health benefits of improving housing conditions

Trenholme and colleagues summarise the persuasive evidence about the important contribution of housing conditions to high rates of child admissions for respiratory disease. New Zealand now has overwhelming research evidence about the advantages of reducing exposure to household crowding3,4 and the benefits of home insulation and heating.5,6 Better housing conditions would support Government’s admirable target to reduce the incidence of rheumatic fever by two-thirds by 2017.7

As mentioned by Trenholme, probably the most compelling evidence for the health benefits of housing improvement comes from evaluating the effects of the Housing New Zealand Corporation (HNZC) Healthy Housing Programme. This programme focussed on housing improvements (insulation, ventilation, heating, crowding reduction) and improved access to primary health care and social services. The largest proportion of households receiving this intervention were in Counties Manukau. Two separate evaluations showed that this programme was extremely effective at reducing rates of hospitalisation for children living in intervention household8,9 and underscored this is as a critical area for further investment.10

The case for Government action on housing supply and quality

There is abundant evidence that the housing market has failed to deliver both the quantity and quality of housing needed. We have historically low levels of building consents particularly in affordable housing.11 This situation has caused a growing housing crisis in Auckland, which has the most rapid population growth in the country and has a shortfall of new house construction of at least 4000 a year.12 This situation is compounded by the Christchurch earthquake, which has destroyed an estimated 11,000 houses.13

An inevitable consequence of a shortage of affordable housing is household crowding. Exposure to severe household crowding (a shortage of two or more bedrooms) is far more common for Māori children (10% of those under 15 years at 2006 Census) and Pacific children (21%) than for European/Other children (2%).14

Thousands of children are experiencing severe housing deprivation,15 officially defined as lack of access to minimally adequate housing.16 These children are living in situations where they have no security of tenure, little privacy, and in some cases not even basic amenities.

In addition, the housing market has produced a legacy of old housing stock that is generally of poor quality and particularly in the case of private rental housing, has high levels of deferred maintenance.17 The litany of problems is now familiar: poorly insulated, inadequately heated, damp and mouldy housing. Added to this is the stock of ‘leaky’ homes which have severe weatherproofing issues.18

These problems are further compounded by ‘functional crowding’ where children and other household members all sleep in the same room to keep warm during cold winter months.2 An important driver for households behaving in this way is fuel poverty, where, as the Trenholme article highlights, an increasing proportion of low income people cannot afford to heat their homes.19 Structural and functional crowding has the obvious potential to greatly increase transmission of infectious disease.

The case for more active Government intervention in the housing market therefore appears overwhelming. This need has been recognised already by the current Warm Up New Zealand programme which has insulated 188,000 homes. This programme was supported by several controlled trials5,6 and economic evaluations20–22 showing health benefits and positive benefit-to-cost ratios.

There is now a strong case for large-scale construction of social housing in Auckland and Christchurch. Housing should be seen as important national infrastructure as proposed by the Expert Advisory Group on Solutions to Child Poverty convened by the Office of the Children’s Commissioner.13 Continuing that logic, we could begin to talk of ‘housing of national significance’ in Auckland and Christchurch (and balance the benefits of investing in this infrastructure against ‘roads of national significance’).

Additionally, Government needs to use its considerable regulatory powers to improve housing quality in New Zealand. A useful mechanism would be to introduce a ‘warrant of fitness’ for rental housing supported by an appropriate regulatory framework. Young children spend virtually all of their time in the home environment, much of which is poor quality rental housing.23

A warrant of fitness could require basic health and safety features such as insulation and protection from falls. Again, such a measure is a key recommendation of the Expert Advisory Group on Solutions to Child Poverty.13 New Zealand has already established a validated tool for measuring the health and safety of housing, the Healthy Housing Index.24 Application of this tool has shown that there is a significant association between the number of respiratory symptoms (wheezing or whistling when breathing, or an asthma attack) of occupants and the number of respiratory hazards in a house.25 A similar association has been found between the number of home injuries (ACC claims) and the number of injury hazards in the house.26

Finally, HNZC should reinstate a realistic level of funding for its very successful Healthy Housing Programme. This programme could be extended to cover all of its 69,000 properties which contain many of New Zealand’s most vulnerable children.27

Using the power of child health information

The high proportion of children admitted to hospital with potentially harmful exposures at home raises the question as to whether these children should be routinely screened for such exposures. Where we have such strong evidence that poor housing is making children sick, it doesn’t make health or economic sense to return them to the conditions that are making them ill.

An obvious barrier to active screening is the probable lack of suitable housing alternatives in a deteriorating housing market such as Auckland. In the medium to longer term, systematic screening for harmful housing exposures needs to be considered for all children admitted to hospital with respiratory illnesses. There are good reasons to focus on respiratory illness given its large, and increasing contribution to hospital admissions.28

From a public health surveillance perspective,29 it would be useful to consider periodic surveys of the prevalence of housing exposures in children admitted to hospitals (covering the sorts of exposures described in the Trenholm paper1 and a recent survey of paediatric admissions in Wellington2). Such information could be used to guide and evaluate policies and programmes aimed at improving housing quality and supply and related activities such as reducing tobacco smoke exposure. These data could potentially add to the excellent child health surveillance reporting now operating in NZ.30


Evidence, ethics, and economics all point towards investing in better housing for children. The Trenholme paper and other commentators remind us of the compelling arguments for taking action to improve child health.13,31 A good starting point would be a warrant of fitness for rental housing and a reinvigorated HNZC Healthy Housing Programme.

Establishing a large-scale programme for construction of medium-density social housing in Auckland and Christchurch would also produce many benefits. Not only would such housing reduce crowding and improve child health, it would also provide a valuable economic stimulus and help retain skilled labour in New Zealand.

Author Information

Michael G Baker, Professor and Co-director, He Kainga Oranga / Housing and Health Research Programme, University of Otago, Wellington; Philippa Howden-Chapman, Professor and Director, He Kainga Oranga / Housing and Health Research Programme, University of Otago, Wellington


Dr Michael Baker, Department of Public Health, University of Otago, Wellington, Box 7343, Wellington, New Zealand 6242. Fax: +64 (0)4 3895319

Correspondence Email


Competing Interests



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  15. Amore K, Baker M, Howden-Chapman P, Viggers H. Severe housing deprivation: The problem and its measurement. Official Statistics Research Series, 6. To be available from Statistics New Zealand's website www.statisphere.govt.nzforthcoming
  16. Statistics New Zealand. New Zealand Definition of Homelessness. Wellington: Statistics New Zealand, 2009.
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