This story was first published on May 27, 2007 and has been resurfaced as cold temperatures continue to plummet this winter.
Shockingly almost 1600 Kiwi deaths each winter are attributed to our cold houses. Here’s what we can do to ward off the worst of winter.
The first cold snap of winter is always a shock, especially after an indifferent summer such as the one we’ve had. It’s the first reminder of how well — or how badly — your home insulation and heating measure up to the coming challenge. And it’s a rude wake-up call for those — almost half of us, according to a recent Statistics New Zealand survey — who say they live in a cold house.
In some cases, the houses of the 48% of Kiwis who are shivering are extremely cold. Research published in 2010 by the Building Research Association (Branz) found that the average evening temperature of New Zealand living rooms during the winter was 17.80C - below the World Health Organisation’s recommended minimum of 180C.
But some were a chilly IOOC. This year, Branz found that almost a third of rental houses feel damp, compared with just 11% Of owner-occupied houses.
Damp houses are much harder to heat than dry ones and the health consequences of cold, damp houses are well known. Children, in particular, are at increased risk of respiratory problems. Just this week, a report published by the Child Poverty Action Group singled out bronchioectasis, a life-threatening disease that results from repeated chest infections in early childhood. The report quotes Asthma and Respiratory Foundation figures showing the incidence of bronchioectasis, which causes lifetime lung damage, almost trebled between 2001 and 2015. Substandard housing, it said, has been identified as “the most important risk factor” in a range of childhood respiratory diseases. Older people, too, are at higher risk of cardiovascular illness from living in cold houses.
According to Philippa HowdenChapman, professor of public health at the University of Otago, that’s because being cold stresses the immune system, puts a burden on the cardiovascular system and makes the muscles work harder in the form of shivering, which helps the body generate heat. “We know that being cold has an impact on older people’s circulation, in particular because the blood gets more viscous and is more likely to form plaques, and people are more likely to have atrial fibrillation, or stroke and malfunctioning of their heart.”
Her research has found many New Zealanders report shivering in their houses; a recent study involving 656 teenagers from 17 low-decile schools, for example, found that 70% reported shivering at least once during the winter. And she says the time-honoured New Zealand tradition of putting on another jersey or piling more blankets onto your bed is not the answer. A recent Japanese study compared a group of healthy volunteers who slept at a temperature of 22°C with those who slept at 12°C but with access to as many blankets as they wanted. “When members of the second group got up in the morning, their blood pressure was much higher, because their bodies were struggling to keep warm.”
Those findings are echoed in a 2014 Scottish study that found that people living in houses with temperatures below 18°C were more likely to suffer from high blood pressure than those living in houses where the temperature was 18°C or higher. The risk was even higher once the temperature dropped below 16°C. Howden-Chapman, the director of the university’s He Kainga Oranga Housing and Health Research Programme, has been instrumental in putting the spotlight on the poor quality of many New Zealand houses.
In her 2015 book, Home Truth: Confronting New Zealand’s Housing Crisis, she wrote that she was often embarrassed by the reaction of overseas audiences when she talked about New Zealand housing and our high winter mortality rate. About 1600 deaths each winter are attributable to cold housing, most of them from respiratory and circulatory problems among older people. New Zealand is not alone in this, she wrote, “but it is one of only a few countries — the others being Scotland, Ireland, Portugal and Greece — that have noticeable winter deaths.
Even in much colder, continental countries such as Canada, the Scandinavian countries and Russia, few such winter deaths occur.” She says we could achieve the same outcomes as in those cold countries if our houses had proper insulation and energy-efficient heating to keep them at the WHO-recommended temperature of 18-21°C. And she has the evidence to prove it. In 2012, she worked with non-profit research institute Motu Economics to evaluate the “Even in much colder Canada, Scandinavia and Russia, few such winter deaths occur.” first 45,000 homes retrofitted with insulation under the Government-funded Warm Up New Zealand programme. They found that the programme had a 6:1 benefit-to-cost ratio for children and older people, and a 4:1 ratio overall.
In other words, every dollar spent on insulation provided $4-6 worth of benefits, mainly by way of reductions in health expenditure because of fewer hospital stays and lower pharmaceutical costs. The programme also saved lives: one for every 1000 insulated houses. Warm Up New Zealand provides subsidies of 33-60% towards the cost of retrofitting homes with ceiling and underfloor insulation. It’s had several iterations since it began in 2009 and by the end of June 2016 had provided a total of $447 million to help insulate 291,000 New Zealand houses.
The programme’s latest — and, at this point, final — version, which is funded to the tune of $18 million and ends in July 2018, focuses on landlords with tenants who have Community Services Cards or health conditions caused by cold, damp housing. The subsidy is intended to help landlords meet the requirement to insulate their rental properties by July 1, 2019. By the end of March, the Energy Efficiency and Conservation Authority (EECA), which administers the programme, had paid out 2946 grants to cover half the cost of retrofitting insulation in rental properties.
Howden-Chapman is disappointed that given its proven health benefits, Warm Up New Zealand is winding down, particularly as she estimates that there are still 600,000- 900,000 New Zealand houses with no or inadequate insulation. “It’s very difficult with the type of houses we have, especially with the older ones, to keep them warm. That means it’s absolutely essential that all homes are insulated, which is why I lament the Government’s decision.”
Arthur Grimes, senior fellow at Motu Economics and former chairman of the Reserve Bank, agrees that it makes financial sense to continue with some targeted insulation subsidies, especially for homeowners aged 60 or older who are at the greatest risk of developing circulatory problems. “This is where you get the biggest bang for your buck when it comes to insulation. They might not have heart disease now, but they may get it later, and I would say that as a group they should be targeted.”
Health payoff
Many people assume that installing insulation will reduce their power bills, but Grimes says that in most cases people spend much the same on energy — but they are much warmer and healthier. “That was a pretty crucial finding we made when we did the evaluation, and it was different from what the officials were expecting, which was sav- ings in energy bills. They did fall a minimal amount, but in fact you wouldn’t get the health benefits if you were cutting back on your energy use.”
As Howden-Chapman points out, having a warm, dry house isn’t just good for your health; it also makes your house easier to maintain: “I tell people that having an even temperature over their whole house is better for their lungs, it’s better for their heart and it’s better for the building.” She finds it hard to understand why anyone who can afford to pay for insulation and energy-efficient heating would opt not to do so and believes the whole “toughing it out during the winter” mentality may be unique to New Zealand.
“There’s quite a macho thing in New Zealand when it comes to heating. You would think that keeping warm was such a pleasure that if you had the money, you would want to keep warm, but that doesn’t seem to apply in New Zealand. Even wealthy people choose to heat just one room.” Those on low incomes, however, have no choice about skimping on heating costs.
University of Otago research suggests that around a quarter of New Zealand households on average (the proportion varies from 18% in Auckland to 46% in Dunedin) suffer what is known as fuel poverty, which means they are spending more than 10% of their income on fuel. That makes it even more important to get: the maximum possible benefit from the fuel you do pay for.
Installing ceiling and underfloor insulation is an important first step to a warmer, drier house. But the good news is that there are other low-cost ways to stay warm in the winter. David Pierce, a healthy-homes assessor for the Wellington-based Sustainability Trust, has helped hundreds of low-income clients - most of whom live in rental accommodation — to make their homes warmer and drier. But he says even home owners who can afford to pay higher power bills can benefit from the changes he recommends.
“Most New Zealand houses could do with some tweaking,” he says. His recommendations revolve around four main things: reducing heat loss, ventilating, reducing moisture levels and making the most of heat from the sun. Once you’ve tackled those four things, you can start thinking about the best way of heating your house.
Pierce says that even if you can’t afford a heat pump, a flued gas heater or a wood burner, you can still get good value from a standalone electric heater — preferably a micathermic one, which combines radiant and convection heat. It’s important to use one that is powerful enough to do the job. Less-powerful heaters are cheaper to run, but they also take longer to heat a room and may end up costing you more.
Time management
Pierce also recommends using timers to turn on heaters in bedrooms an hour or so before you go to bed and again before you get up. “That’s particularly important for children and also for elderly people, as going from a warm living room into a cold bedroom can be a health risk.” And don’t underestimate the usefulness of lined, floor-length curtains with a pelmet or a face-fixed track that sits close to the wall. “You won’t find a pelmet in any of the home-decorating magazines at the moment, but face-fixed tracks work just as well.
You may not be able to afford double glazing, but some decent curtains will help deliver the comfort you’re after.” Pierce says his clients are often surprised at how much difference these simple measures make. “Often they spend about the same on energy, but they’re getting more heat benefit. That means they have fewer hospital and doctors’ visits, better sleep, fewer colds and flu and improved well-being.”
Double glazing holds the heat in better
Changes to the Building Code in 2008 made double glazing compulsory for most new houses. However, more and more homeowners are choosing to replace their existing windows with double glazing. Double glazing creates an insulating layer of gas — either normal air or special heavy gases — between two panes of glass. It lets in just as much sunlight as single glazing, but is better at holding in heat.
Retrofitting double glazing may mean installing a new window, or alternatively what’s known as secondary glazing, which involves inserting a second pane of glass or acrylic into an existing window frame.
It’s also possible to fit temporary double glazing yourself, using a flexible clear film that’s attached with double-sided adhesive tape to the window frame. You then use a hair dryer to tighten the film. According to the Energy Efficiency and Conservation Authority (EECA), double glazing can halve the amount of heat lost through windows, depending on the type: the most effective is made of low-emissivity (low-E) glass with a layer of argon gas between the two panes, fitted into either thermal aluminium or wooden frames.
Retrofitting permanent double glazing is expensive — as much as $1000 a square metre — and it provides less thermal benefit than ceiling and underfloor insulation. In some cases, good curtains may be just as effective. “The first line of defence against the heat loss around windows is a good set of floor-length, double-lined curtains,” says David Pierce of the Sustainability Trust. “Double glazing will improve heat retention, but it’s too expensive for some. Its value lies mostly in the improved overall comfort it delivers, including reduced condensation and noise from outside.”
The further south you live, the more financial sense retrofitting double glazing makes. A study published in 2010 by Victoria University master of building science student Nick Smith found it would take 28 to 30 years to recoup the cost of secondary glazing in Auckland, compared with 13 to 15 years in Dunedin. Smith’s study also gave the thumbsup to temporary double glazing, which can be installed in a typical living room for less than $100 — though it lasts for only one winter. He found using the thin film paid for itself in heating savings in Wellington, Christchurch and Dunedin, but not in Auckland.
Not all electric heaters are created equal
Heat pumps are cheaper to run than any other form of heating. According to George Block, Consumer NZ’s heating and energy specialist, for every kilowatt of power that goes into a heat pump you get 3-4KW out. Next cheapest are flued gas heaters and wood burners, which also offer a different Kind of heating experience.
“You can’t sit in front of a heat pump with a glass of brandy and read a book,” says Block. However, all three types of heating are expensive to buy and install — more than $3000 in some cases — which makes them unaffordable for people on low incomes, and unrealistic for renters who can’t take them with them when they leave.
It’s possible to buy a 2.4kW electric heater capable of heating a medium-sized living room for less than $100, though it will cost about 60c an hour to run, compared with about 38c for a 4.5kW heat pump. It will also take much longer than more energy-efficient heating to warm the room to your desired temperature. You might think that, apart from the way they look, plug-in electric heaters are all pretty much the same, but Block says that’s not the case.
“There are differences in how quickly and how evenly they warm a room.” Consumer tests have found that oscillating tower fan heaters heat rooms faster and most evenly. They have their downsides, though: they look slightly odd — the name is a bit of a giveaway - and tend to be noisy. If noise bothers you, your next best bet is a micathermic heater. These have sheets of mica (a mineral similar to slate) encased in a metal housing, which heat up quickly. They also provide a combination of convection and radiant heat, which means that as well as heating the air in a room, they also heat the objects in it — including humans.
That means that you will feel warmth coming from the heater. On the downside, the surface of micather- mic heaters can get very hot, which may pose a danger for children. The least effective plug-in heaters are oil column heaters. These are slow to heat up and take longer to heat a room, because they provide almost exclusively convection heat, which rises towards the ceiling and only gets to objects lower down as it cools and falls.
However, Block says they are popular because they’re quiet and their surfaces stay relatively cool. A small desk fan can help make both micathermic and oil column heaters more effective.
Consumer found that putting a small fan on the floor facing an oil column heater raised the average room temperature by S°C three times faster than when using the heater without the fan. It’s important to get a heater that is powerful enough to do the job — at least 2kKW for a medium-sized living room. A less-powerful heater is cheaper to run, but it will take longer to heat the room, effectively cancelling out any possible savings.
When Consumer compared a 0.4KW panel heater with a 2.3kW oil column heater, it found the panel heater took 21 minutes to raise the temperature of a room from 8°C to 10°C, compared with just 8.2 minutes for the oil column heater. You can use the heater’s thermostat and a timer to help control how long your heater is on and keep your power costs down.
Most heaters have a thermostat, but not so many have timers. However, you can buy a cheap digital timer from a supermarket or hardware store. Block also recommends checking Consumer’s Powerswitch website to find the cheapest electricity and gas plans in your area. “There’s so much variation and so much competition in the retail space that you can save $500 to $600 a year by switching power companies.”
Cut costs and warm up
Control indoor moisture
Moist air provides a breeding ground for mould, which has been linked to respiratory illnesses. Moist air is also harder to heat, so keep your home as dry as possible, Use extractor fans if you have them, or open a window when you’re cooking and showering - and never dry laundry inside. David Pierce from the Sustainability Trust also recommends laying a sheet of heavy polythene on the ground under your house to stop moist air coming through the floor. “It’s relatively inexpensive and it’s certainly within DIY territory,” he says.
Ventilate
Airing your house regularly helps remove airborne bugs and reduces overall moisture levels. “The air outside is generally drier than inside air, even on a wet day,” says Pierce. He recommends opening a couple of windows for at least 15 minutes a day - preferably at opposite ends of the house to create a through breeze.
Reduce heat loss
Installing ceiling and underfloor insulation is an important first step in making your house warmer and drier. Block off unused chimneys and get lined curtains that reach the floor - their length helps stop cold air trapped behind the curtains from escaping into the room. A pelmet, or even a rolled-up towel behind the curtain track, can also help make curtains more thermally efficient. You can also use rolled-up towels or a traditional “door snake” and put draught tape inside door and window frames to help retain heat and stop cold air from coming in. “Draughts account for 12-14% of heat loss,” says Pierce.
Make the most of the sun
You can’t reorient a south-facing house, but you can make the most of any northern winter sun you do get. Pull your curtains in the morning — including net curtains, which can stop sunlight from coming in - and close them again when the sun goes down to retain the heat in your house.
