Next, heating. The World Health Organisation recommends we heat our homes to at least 18C.
That's partly for health and comfort, but also reduces the risk of mould and damp. The most environmentally-friendly and cost-effective heat sources — particularly for larger rooms — are energy efficient heat pumps or modern wood or wood-pellet burners.
You also need proper ventilation for good air quality and to remove excess moisture. And no, living in a draughty house doesn't count. According to Hoerning, adequate ventilation means opening windows at opposite ends of the house every day and using externally venting extractor fans in the kitchen, bathroom and laundry.
"It's also important to track down any underlying sources of damp in your home because some of these — such as leaking pipes — can be relatively simple to fix," he says.
If your property has accessible subfloor spaces, Hoerning recommends installing a ground moisture barrier. This stops moisture rising up from the ground into the house.
Need to replace an appliance or lighting? It pays to go green.
Hoerning says: "It costs as much to run one old-fashioned incandescent lightbulb as it does to run a modern, energy-efficient television. LED lightbulbs are now an affordable option that will save households money."
Check out which appliances are most energy-efficient — and therefore the cheapest to run — using EECA's new Rightware tool. It's free at energywise.govt.nz.
Adopting these basic measures to improve your home will pay back big time when it comes to health — for you and the planet.