How to keep your NZ home cool during summer

Opening windows and doors might seem like the obvious thing to do to cool your home down in summer. But doing this at the wrong time of year could actually make things worse – so you need to do this tactically.

To improve airflow and reduce indoor heat, try opening windows on opposite sides of the house. This helps to release trapped warm air and draw in cooler outside air, especially when the outside temperature is lower than indoors, which typically happens overnight or in the early morning. It’s likely that, by mid-morning, outdoor temperatures in NZ summer will be warmer than your home’s interior, so opening the doors and windows will actually make your home hotter.

Warm air naturally rises and can become trapped in your home, particularly in the upper levels. If your property has loft vents or windows, opening them can allow the heat to escape, preventing it from accumulating in areas like your bedroom. Consider opening the loft hatch to let hot air rise and dissipate more effectively.

Also, in the same way that you’d use draft excluders to keep your home warm during the winter to stop heat escaping, you want to plug any gaps around windows and doors in summer to stop hot air getting in.

Once it gets to the hottest part of the day (usually between 2–4 PM), you’ll need to rethink what you’re doing with your windows, particularly if they get direct sunlight.

According to Family Handman, up to 30% of unwanted heat in a home can come in through windows. So, the best thing to do in this situation is to close your blinds or curtains to keep as much of this heat out as possible. It might seem counterintuitive, but trust us, it works.

Placing a fan in front of an open window can help pull cooler outside air into the room, provided the temperature outside is lower.

For an added cooling effect, try positioning ice cubes in front of the fan, which will chill the air it blows towards you. You can also use multiple fans to create a cross breeze, enhancing airflow throughout the space.

However, if you’re using a pedestal fan, ensure it's directed towards the window. This will help push the hot air out of the room, allowing cooler air from outside to flow in.

Also think about the position and height of the fan relative to you. For example, fanning your face will probably seem to be effective for improving your comfort levels, but fanning your entire body will actually be most effective for reducing your body temperature.

Using your oven or cooktop can significantly increase the temperature in your kitchen, and the rooms around it, not only when they’re turned on, but for some time after.

So, if you really want to keep the temperature in your home as low as possible, you might want to rethink what’s on the menu for dinner. Salads are great in summer anyway – and they mean you don’t need to raise the temperature unnecessarily.

Of course, another obvious option is to fire up the BBQ outside, as this won’t make your interiors any warmer…like we needed an excuse to fire up the BBQ!