Cool Living
ed. Hot Dry
TECHNICAL
Heat & Health
Extreme heat is a well-documented cause of immediate and long-term adverse health impacts, particularly in at-risk groups.
Extreme heat exacerbates many pre-existing health conditions. Adverse health conditions associated with high climatic temperatures are generally termed ‘heat stress’ and include heatstroke, heat exhaustion, heat syncope (fainting/unconsciousness) and heat cramps. The mildest forms of heat-related illnesses, which respond well to outpatient treatment, are heat rashes or prickly heat, heat cramps, and heat syncope. Heat exhaustion and heatstroke are far more serious and can be fatal even with prompt medical care.
Infants and Young Children (susceptible population)
The risk of heat-related illness and fatality are high among infants and young children. Young children are more vulnerable to heat illness due to their reduced ability to sweat, larger body surface area per body mass, increased risk of dehydration and rapid rises in core body temperature if dehydrated. Also, infants and children under five years are sensitive to heat. Conditions such as mild fever can progress quickly to heatstroke if heat stress occurs.4 Extreme temperatures affect the ability to resist infection, particularly among young children.
In Aboriginal communities, malnutrition is a major health concern. Aboriginal infants have a lower average birth weight, and 14% of Aboriginal infants and 22% of children in Western Australia have been reported as being underweight. During high environmental temperatures, Aboriginal children with malnutrition are at risk of heat-related illness and death. The likelihood of heat intolerance in children increases with conditions that are associated with excessive fluid loss such as abnormal hypothalamic thermoregulatory function (regulation of body temperature, water balance, etc.). Such abnormal function occurs in advanced malnutrition and where there has been a prior episode of heat-related illness.
Elderly (susceptible population)
The elderly are susceptible to heat-related illness due to their reduced ability to adjust to physical changes in the body, which occur when exposed to excessive heat. The elderly are also at greater risk of heatstroke because of their increased likelihood of chronic medical conditions (like cardiovascular disease and peripheral neuropathiesa), use of medication, and their reduced mobility in terms of removing themselves from hot environments.
Some of the medications taken by the elderly that increase the risk for heat-related illness include tranquilizers, anticholinergicsb, diuretics (which can further rob the body of fluids), antihistaminesc and phenothiazinesd. The latter two both decrease the body’s capacity to sweat.
In Australian capital cities, it has been estimated that 1,100 people aged over 65 die each year from extremely hot temperatures. Australian studies have noted increased sensitivity among the elderly to prolonged spells of hot or cold and also sudden falls or rises in temperature.
Healthabitat
Since 1985, Healthabitat has worked with Indigenous communities throughout Australia to improve the health performance of more than 10,000 houses through understanding house function, providing targeted repairs and maintenance and data collection on benefits to the house. Housing for Health—the methodology that underpins this work—adopts nine Healthy Living Practices (HLPs) to understand how the built environment hierarchically impacts upon people’s health.
As climate change continues to destabilise who gets to live where and on what terms, architects must understand how their particular skillset—and the labour that sits behind it—can meaningfully assist communities in resisting the broader forces of uneven development.
HLP8 - Controlling the temperature of the living environment
Living in houses that are too cold or too hot can contribute to a range of physical illnesses and can cause emotional distress for residents. Extended exposure to high temperatures can also result in illness, with increased risk of dehydration and heat stress for sick children and elderly people.
It can be expensive to use ‘active’ heating and cooling systems, such as heaters and air conditioners to make poorly performing houses more comfortable. Houses that incorporate passive design features will require less days of active heating and cooling and less energy will be required to heat or cool the house on extreme temperature days. This means reduced costs for the resident.
As a result of the increasingly hot temperatures in the communities in which Healthabitat work, they are reconsidering the significance of HLP #8 (Controlling the temperature of the living environment) and the place in which it sits in the 9 principle hierarchy and within the wider Housing for Health methodology prioritised list.