Beacon

What does insulation do?

Insulation is all about maintaining an even temperature in your home.  In winter it stops the heat escaping from your home, and in summer it stops the heat coming in.  A recent Beacon survey asked homeowners who had recently moved what they had done to make their homes warmer – 38% had installed heat pumps or heat recovery systems rather than insulating their homes.    This is like driving around in a convertible car with the heater on full … and a rip in the roof.  As hard as the heater works, the air will escape out the hole in the roof.  And our survey showed exactly that - nearly half of the homeowners still had problems with cold and damp.

Without insulation, heat escapes from your roof (42%), floor (10%) and walls (24%).     To keep your house warm you are heating far more air than you need as much of it is heading straight outside.  Insulation means your heater, pellet fire, wood burner or other heat source will warm your home much more efficiently.

Why is insulation important?

Living in cold indoor environments is increasingly being linked to poor health.  On average we spend 75% or more of our time at home.  Yet New Zealand homes are too cold and damp: the World Health Organisation recommends that the minimum temperatures for good health are 18ºC for living areas and 16°C for bathrooms.  New Zealand’s homes are often below this.  Recent New Zealand research on housing insulation and health has shown that internal air temperatures below 12oC can have a significantly detrimental impact on health.
 
And it’s not just a matter of warmth.  Cold air holds far less moisture than warm air.  In cold temperatures the moisture naturally in the air settles on cold surfaces such as un-insulated walls, ceilings and windows as condensation.  Condensation and cold are the perfect conditions for growing mould which thrives in humidity greater than 70% on cold surfaces with condensation potential.

Mould, with its tiny spores, is at the root of many respiratory illnesses and asthma as well as some forms of gastroenteritis. Fungi growth affects about 40% of New Zealand homes and can cause adverse health effects such as respiratory illnesses, asthma and allergies.  Dust mites also thrive in humid environments, exacerbating asthma and allergies.

The Otago University Wellington School of Medicine Housing Insulation and Health study found that increasing the temperature in New Zealand homes by only 1°C to 12.7°C significantly reduced the number of hours that the indoor relative humidity was in excess of 75%. 

The Insulation, Housing and Health study found every dollar spent on insulation gave a two-fold return in health savings, in addition to the energy conserved in home heating.  Insulation will keep our homes warmer and drier, and save money on doctors’ visits, prescription fees, sick days and hospital bills by making our hones healthier. Given the cost of retrofitting ceiling and underfloor insulation to an existing home is roughly equivalent to one night’s stay in hospital, insulation is good value.

Valuing insulation

And insulation improves more than just health.  The most striking comments from householders living in homes built or renovated with high insulation in Beacon’s live research projects have been about the greater quality of life they enjoyed.  The Blair family described the change from their previous home to living in the highly insulated Waitakere NOW Home®, as ‘huge’ in terms of mental health and generally being happier.  “We are happy here, which flows through to everything else.  Everything has been better since being here,” says Joe Blair.  “We realised the impact a house could have on the rest of life”. 

Homeowners in houses renovated in Papakowhai also quickly noticed an unexpected consequence of their warmer homes was an enormous sense of well-being and improved family life.  Households described reduced household stress associated with warmer winter indoor environments.