Air leaks are the biggest barrier to keeping your home warm in winter and cool in summer, according to an energy efficiency expert.
- Chimneys, vents, and hidden cracks can all impact the energy efficiency of a house
- The CSIRO says there are various simple fixes to stop air escaping from your home
- Decreasing “leakiness” can have a significant impact on how much you pay for power
Michael Ambrose, a senior experimental scientist with the CSIRO, is blunt when describing the energy efficiency of Australian houses.
“Australian homes rule the roost when it comes to leakiness,” Mr Ambrose said.
“It’s never really been considered an issue.
“We are lucky in that we have a very temperate climate, but means that we haven’t really seen the need to address it.”
But with many of us spending more time at home than ever in the depth of winter, addressing the problem now could help decrease power bills.
“Many things make a house leaky,” Mr Ambrose said.
“But the main thing is where we have got gaps between our nice air-conditioned indoor space to the outdoor space — under doors, around windows, inside cupboards.
“If you have an older home that is raised off the ground, not on a slab, it can be through floorboards.”
Increased home energy efficiency will bring down bills. (ABC News: Ian Cutmore)
It’s also worth checking cupboards, particularly in kitchens and laundries, for hidden leaks.
“[Gaps] can also be hidden away in cupboards where old services were connected — a dishwasher, washing machine,” Mr Ambrose said.
“When they are removed the piping is removed and often the hole that the services came through is left there and no plugged up, and air can escape.
“Go looking, try to find those holes in the laundry and kitchen, you can just get expanding foam [to plug them].”
A fireplace can be blocked up easily with a purpose designed balloon in the chimney. (ABC Radio Perth: Emma Wynne)
If they are not used for a roaring fire in winter, fireplaces and chimneys can also be major source of air loss and draughts.
“A lot of heat gets lost up the fireplace, if it’s not in use,” Mr Ambrose said.
“Some people block their fireplaces off with a cover and you can actually get a chimney balloon that expands and blocks off the chimney.
“You’ve just got to remember to take it out if you want to light a fire.”
Michael Ambrose says door snakes can stop air leaking, while wall vents can let air escape. (Flickr: Agnes Jenkins and Tami Hills)
Another easy spot to target is the air vents in ceilings and walls of older homes.
The vents were a building requirement back in the days when unflued gas heaters were common, and authorities were concerned that the gases they released, such as carbon monoxide, needed an escape route.
“But with new heaters and flued systems the requirement for vents was removed, that’s why you don’t see them in new homes,” Mr Ambrose said.
“If you don’t have an old style heater then we do suggest to people that they can actually cover up those wall vents because they are large source of leaks.”
Mr Ambrose said creating a completely passive, sealed home is an expensive exercise, but products that plug leaks can be bought cheaply from hardware shops.
He suggests door snakes to block draughts and weather sealing strips that can be stuck around door frames are worthwhile.
What you said
Speaking to Jessica Strutt on ABC Radio Perth, listeners shared their own tips on how to plug leaks at home.
Anon: “We have a heritage listed home built in 1925, which has been rehabilitated to be passive. It is nearly airtight, have huge amounts of insulation and the windows etc all work amazingly. We have 3.3 metre high ceilings, floorboards etc. It is better than any modern house I have ever lived in.”
Rosie: “If you have an old fireplace that is not used a lot of warm air escapes from it. Best to block it up during winter.”
Dan: “One of the first jobs I did on our home in the hills was insulate underneath our floorboards. Our home is on stumps and although access was tough it has made a huge difference.”
Donna: “I lived in Minneapolis for eight years where the winters can hit -40C. I learnt to put plastic cling film over our windows in winter, sealing it with a hair dryer to stop any form of fresh cold air coming into the home.
Mr Ambrose suggested using the most efficient heating you can.
“Blow heaters are pretty inefficient. Old gas heaters can be pretty inefficient as well,” he said.
“The most efficient heaters are actually your air conditioner, if it’s reverse cycle. They are a heat pump, the same technology as your fridge.
“For every unit of energy they bring in, they are able to put out about three times as much energy out.”