Summer can be tough in many parts of Australia, but Perth heat has its own challenges, especially if you’re living in or planning to add a granny flat. These handy backyard homes are great for giving families more space, but they don’t always handle warm weather well.

It doesn’t take long for heat, poor airflow, and tricky yard layouts to turn a simple living space into something that feels uncomfortable through the season. If you’re thinking about granny flats in Perth, or already have one, knowing what to watch out for during summer can make a big difference. Here are the most common problems we see and the things worth thinking about ahead of time.

Overheating and Poor Airflow

One of the biggest issues people run into during summer is the build-up of heat inside the flat. The layout plays a major role here. If warm air gets trapped or windows are too small and poorly placed, rooms can turn into ovens by mid-afternoon.

• Many older or budget granny flats don’t have cross-ventilation. That means there’s no breeze pulling air through the space
• Insulation can help, but if it wasn’t installed properly or the roof space heats up, the whole area can stay hot long after sunset
• High ceilings might look nice, but without ceiling fans or vents, they just become places where hot air sits

We specialise in contemporary granny flats that can include custom energy-efficient window placements and ceiling fans for improved cross-ventilation. Paying attention to how your flat will be used each day and planning for airflow makes hot spells much easier to live through.

Limited Shade Around the Structure

Placing a granny flat in the back corner of the yard often seems like the obvious choice. But that part of the block is sometimes where there’s the least protection from the sun.

• Without trees, fences, or any buildings nearby to block sunlight, the entire outer wall can stay in direct sun all day
• Exterior paint finishes can fade or blister over time, especially lighter colours that catch strong UV
• Inside, the heat from sunlit walls and roofs can warm the air even if the blinds are closed

We often look at how shadows move across the yard during the day, especially around midday. Knowing where the harshest light hits in January and February helps us plan where to build and how to angle the roof or add awnings that give cover when it’s most needed.

Inadequate Cooling Setup

Some granny flats use small wall-mounted split systems or just rely on fans, but not all cooling options work well in tight or oddly shaped rooms. In summer, these setups might feel like they’re falling behind by 10am.

• West-facing flats catch the afternoon sun, which is often the hottest part of the day
• Portable units may cool one part of the room but leave the rest feeling warm and sticky
• High ceilings and open-plan spaces can make it harder for cool air to stay where people spend most of their time

We offer eco-friendly solutions, including insulation and cooling systems that are tailored to each individual flat. Starting with the right cooling choice for each space can mean more comfort during heatwaves and fewer surprises on your power bill.

Summer Storm Drainage and Runoff Issues

Summer rains in Perth can hit suddenly and hard. A quick downpour might last only twenty minutes, but it can create a mess if the water has nowhere to go. Granny flats are often built on flat ground where water naturally pools.

• Poor grading around the building can push rainwater toward the base of the flat instead of pulling it away
• Blocked gutters and downpipes turn small storms into drainage problems
• Without proper drainage, water can seep into floorboards or create muddy patches near doors and steps

During summer, it’s not just the heat that causes trouble. Stormwater needs to be managed just as carefully. We make sure the land has a natural fall where possible, with the layout and guttering set up to move water quickly and safely away from the home.

Fire Risk in Dry Backyards

By January, many yards in Perth are dry and brown. If the grass hasn’t been watered or the garden’s a little overgrown, it doesn’t take much for fire concerns to creep in, particularly in older suburbs where fences are close together and homes share boundary lines.

• Backyards with wooden fencing, dry plants, or sheds nearby can raise concerns for fire proximity
• Some materials used in budget builds catch alight faster or give off smoke that makes the area unsafe
• Lawns or garden beds close to the flat can become fire sources if not kept clean and trimmed

Spacing between the flat and nearby elements matters a lot here. We try to think ahead about the kind of materials used and the layout of trees, fences, and bins. Simple planning here can help lower the stress around fire danger days.

Keeping Summer Comfortable in Your Granny Flat

Summer in Perth doesn’t need to be uncomfortable. When we look at how to design, build, or improve granny flats, we start by thinking about things like natural light, heat exposure, and how people actually live in the space every day. Making sure each area of the flat is suited to Perth’s unique weather goes a long way toward keeping it liveable.

From drainage and airflow to safe cooling and shaded outdoor areas, addressing these little pieces early makes the whole space more liveable through January, February, and beyond. With smart decisions around energy efficiency and building placement, it’s easier to manage heat and enjoy your granny flat through the hottest months. Taking the time at the start to plan for Perth’s climate means less discomfort and a more relaxed summer.

Ready for a Cooler Perth Summer?

Summer is the perfect time to notice what works and what could be improved in your granny flat. From airflow to shade, comfort starts with the right design choices. We know what it takes to create spaces that remain liveable throughout Perth’s long, hot days. Discover how we approach granny flats in Perth to ensure year-round functionality, and contact Perway Construction Services to discuss your project ideas.