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Housing, Insulation and Health Study

The Impact of Insulating Domestic Houses on the Health of Occupants: an Intervention Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00437541
Acronym
HIHS
Enrollment
4000
Registered
2007-02-21
Start date
2001-07-31
Completion date
2002-12-31
Last updated
2007-02-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Asthma, Respiratory Illness

Keywords

Insulation, Warmth, Humidity, Damp, Cold, Respiratory, Mould

Brief summary

In six communities we will seek out households where someone who has a history of respiratory problems. For the first winter we will measure temperature and humidity of the house and health of occupants. We will insulate half the houses and the next winter compare them with the uninsulated houses to see if warmer houses improve health.

Detailed description

Damp, cold indoor environments are bad for the health of people who live in them, particularly if they have respiratory problems or are vulnerable, such as the young or the very old. This is a community based study designed to test the hypothesis that insulating domestic houses will make them warmer and that this increase in indoor temperature will improve their health and wellbeing. Following two pilot studies, the first among older people in city council flats and the second among home owners in Waitara. We have followed the Waitara model where community networks will be mobilised to identify households in each community where there is someone with a on going respiratory problem. Seven communities have been selected to help test these hypotheses and have agreed to participate Otara, Gisborne, Mahia/Nuhaka, Taranaki, Porirua, West Coast and Christchurch. Low income areas with high Maori populations have been deliberately selected to maximise the potential health gains. Two hundred houses in each community will be insulated free of charge to the occupants. The workers who will insulate the homes will be local people employed through the Department of Work and Income (WINZ). Once the houesholds are selected they will be randomly assigned to intervention or control groups. During the first winter, all 1400 households will be monitored for temperature and humidity and their comfort, health and healthcare utilization will be recorded. Half the households, assigned to the intervention group, will be fully insulated during the spring. The following winter, all the initial measurements taken from both the intervention and control group will be repeated. At the end of the study period, all control houses will be insulated. This study has developed from a natural intervention being carried out by the Energy Efficiency Conservation Authority (EECA) to insulate domestic houses in New Zealand and is a major collaborative effort, which will shed light on the effectiveness of insulation in improving health and wellbeing. The impact of housing refurbishment on health has not previously been examined. There is considerable government and policy interest in promoting healthy housing and there is strong community interest in ensuring the housing stock is improved in order to lower health risks.

Interventions

DEVICEInsulation retrofitted into house

Sponsors

University of Otago
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Healthy volunteers
No

Inclusion criteria

* Live in Study area * At least one person in the household must had had respiratory illness within the last year, well members of the same household may also participate * house currently uninsulated * interested in taking part in research

Exclusion criteria

* Intending to move within study period

Design outcomes

Primary

MeasureTime frame
Self reported general health, During the first winter post intervention
Indoor temperature and relative humidity, During the first winter post intervention

Secondary

MeasureTime frame
Days off school and work, During the first winter post intervention
Energy consumption, During the first winter post intervention
Inpatient hospital admissions, During the first winter post intervention
GP visits, During the first winter post intervention
Wheezing, During the first winter post intervention

Countries

New Zealand

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026