Is Your Home Too Hot in Summer? Here’s How to Keep It Cool
15 October 2026
We spend plenty of time thinking about keeping our homes warm in winter, but what happens when summer arrives and your house feels more like an oven?
Summer in Southland can bring some beautiful sunny days. But when the sun streams through the windows and the temperature starts climbing, keeping your home comfortable can become a challenge.
And it’s not just about feeling a bit too warm. An overheated home can make it difficult to sleep, leave you feeling uncomfortable and have you reaching for the air conditioning.
The good news? There are some practical ways to keep the heat out, improve your home’s comfort and reduce the need for cooling.
Why does your home get so hot?
During summer, heat enters your home in several ways, but one of the biggest culprits is sunlight coming through your windows.
Large windows, particularly those facing north and west, can let in plenty of sunshine. That’s lovely in winter when you’re trying to warm the house, but in summer it can quickly push indoor temperatures up.
Your roof also absorbs heat from the sun, which can transfer into your living spaces, especially if your ceiling insulation is inadequate.
And once that heat gets inside, it can be surprisingly difficult to get rid of.
Stop the heat before it gets inside
One of the most effective ways to keep your home cool is to stop the sun heating it in the first place. External shading is particularly effective because it blocks sunlight before it passes through the glass.
Consider:
- Outdoor blinds or awnings over sunny windows.
- Shade sails or appropriately positioned pergolas.
- Deciduous trees that provide summer shade but let sunlight through in winter.
- Closing curtains or blinds before the sun reaches your windows.
West-facing windows deserve particular attention because the afternoon sun can be intense, just when your home has already warmed up. Even something as simple as closing the curtains in rooms you’re not using can make a difference.
Insulation isn’t just for winter
When we talk about insulation, most people think about keeping their homes warm. But good insulation helps keep your home cooler in summer too. Insulation slows the movement of heat through your home’s ceiling, walls and floors. In winter, that helps keep warmth inside. In summer, it helps slow heat entering from outside.
Ceiling insulation is particularly important because your roof can get very hot when the sun is shining. If your home has little or no ceiling insulation, that heat can transfer into the rooms below.
Of course, insulation works best alongside good shading and ventilation. It won’t stop sunlight pouring through an unshaded window, but it can make a real difference to how quickly your home heats up.
Get smart with your windows
Opening every window on a hot afternoon might seem like the obvious way to cool your home. But if the air outside is hotter than the air inside, you could actually be making things worse.
Instead, try working with the temperature.
Early morning: Open windows and doors when the outdoor air is cooler to flush out warm indoor air.
During the hottest part of the day: Close windows where hot air is entering and use curtains or blinds to block direct sunlight.
In the evening: Once the outdoor temperature drops, open windows again to let cooler air circulate through your home.
Opening windows on opposite sides of the house can encourage cross-ventilation, helping move warm air out and cooler air in. Just remember to consider security and insect screens when leaving windows open.
Use your heat pump for cooling
Your heat pump isn’t just there for those chilly Southland mornings! Most reverse-cycle heat pumps can also cool your home, making them useful all year round.
A few tips to help your heat pump work efficiently in summer:
- Select cooling mode, usually shown by a snowflake symbol on the remote.
- Start with a comfortable setting of around 24°C to 26°C and adjust to suit your home.
- Keep doors and windows closed while it’s cooling.
- Close curtains on sunny windows to reduce the amount of heat coming in.
- Keep filters clean and make sure airflow isn’t blocked.
Setting your heat pump to an extremely low temperature won’t necessarily cool the room any faster. It may simply make the unit work harder and use more electricity. And if your heat pump isn’t performing as well as it should, it may be time for a professional service.
Think about your home’s overall comfort
If your home becomes unbearably hot every summer, it might be worth looking beyond quick fixes. Every home is different. The amount of insulation, window size and orientation, shading, ventilation and heating and cooling systems all affect how comfortable your home feels.
For example, a sunny living room with large west-facing windows might benefit most from external shading, while a bedroom directly beneath a poorly insulated roof may need improved ceiling insulation.
The best solution depends on what’s causing the problem. That’s why it’s worth looking at your home as a whole rather than simply turning up the cooling.
A comfortable home is for every season
At Awarua Synergy, we’re passionate about helping Southland households enjoy warmer, healthier and more comfortable homes.
And that doesn’t stop when winter ends.
Whether you’re trying to keep the heat in during July or keep it out in January, the right combination of insulation, shading, ventilation and efficient heating and cooling can make a big difference.
Is your home too hot in summer or too cold in winter?
Book a free home assessment with Awarua Synergy. Our friendly team can help you understand where your home could be more comfortable and recommend practical improvements to suit your property.
