Perth regularly sees summer days above 40°C, and a growing number of its homes have polished concrete floors. The two are connected, and not always in the way new arrivals expect. This piece looks at how a polished slab behaves through a Perth summer and winter, and what it means for British families used to carpeted, suspended timber floors.
How Perth houses are built
A large share of Perth houses, particularly from the 1970s onwards, are double brick built on a concrete slab laid directly on the ground. That is different from most of the eastern states, where brick veneer on a timber frame is more common, and very different from a British semi with a suspended timber floor over a void.
In many of these homes the slab has traditionally been covered with carpet, tiles or floating timber. Polishing removes that layer and makes the slab itself the finished floor. The concrete is ground back with progressively finer abrasives, sometimes exposing the stone in the mix, then densified and either sealed or honed to a sheen. On older slabs the result depends heavily on the condition and the original mix, so expect some variation in colour and texture.
Because so much depends on the slab you already have, it is sensible to read a local specialist’s guidance before committing. The information at polishedconcretefloorsperth.au covers the grinding, finish and sealing options for Perth slabs and is a reasonable place to start before asking for an assessment.
Thermal mass and the 40-degree day
Concrete is dense. It takes a long time to warm up and a long time to cool down, a quality known as thermal mass. On a hot day, a shaded slab in contact with the ground absorbs heat from the room air and releases it slowly, which helps keep indoor temperatures steadier. Walk barefoot onto a polished floor in a darkened room in January and it feels pleasantly cool.
That benefit depends on the slab staying in shade. Thermal mass works in both directions. A polished floor sitting in direct afternoon sun through a west-facing window will soak up heat for hours and give it back into the evening, which is exactly when you want the house to cool down. The common approaches are external blinds, eaves of a decent depth, and keeping the curtains drawn on the west side through the hottest part of the day.
Perth also has the advantage of the afternoon sea breeze, locally called the Fremantle Doctor, which arrives on many summer afternoons. Opening the house up once it comes through, and again overnight when the outside air drops below the inside temperature, lets the slab shed heat. Close up again in the morning before the heat builds. Double brick walls and a polished slab together make that rhythm quite effective.
The other side: winter
Perth winters are mild by British standards, but they are wet and nights can drop to single figures. Many Perth houses have little or no insulation under the slab, so the floor stays at something close to ground temperature. In July a bare polished floor can feel cold underfoot, and British families often find the house chillier than they expected.
Rugs solve most of this. They sit over the areas where people actually stand and sit, add some sound absorption, and can be rolled away when summer returns. Slippers do the rest. Hydronic underfloor heating can be laid in new slabs, but retrofitting it into an existing polished floor is generally impractical, so it belongs to a new build or a full renovation conversation.
Winter sun is the opposite of summer sun. Letting low northern sun fall across the floor during the day allows the slab to collect some warmth and release it into the evening, which is another reason to think about shading in seasonal terms rather than closing everything all year.
Dust, allergies and day-to-day care
For families who arrive with a child sensitive to house dust mites, a hard floor is often a relief after wall-to-wall carpet. Dust stays on the surface where a dry mop or vacuum picks it up, rather than settling deep into pile. Perth’s dry, dusty summers mean floors need regular sweeping, but the job is quick.
Care is fairly simple. Use a pH-neutral cleaner, avoid harsh acids and bleach that can etch the surface, and put felt pads on furniture legs. Grit carried in on shoes acts like sandpaper over time, so a mat at each door does more than any polish. Sealed floors may need resealing after some years, depending on the system used and the traffic.
There are drawbacks to weigh. Hard floors carry sound, so a house with a lot of polished concrete can feel echoey until rugs and soft furnishings go in. Dropped glasses break. A slab with old cracks will show them, and new hairline cracks may appear as the concrete continues to move slightly. Most owners treat these as part of the character, but it is better to know in advance.
Questions readers ask
Can any existing slab be polished?
Most can be ground and sealed, but the look depends on the concrete underneath, and old glue, paint or patching can leave marks. A contractor will usually want to inspect the slab, often after lifting a small section of the existing covering.
Will polished concrete make the house cooler on its own?
Only if the slab is kept out of direct summer sun and the house is ventilated when the outside air is cooler. Without shading, it can store heat rather than help.
Is polished concrete slippery when wet?
A high-gloss finish can be slippery, particularly near outside doors and in bathrooms. Honed finishes and anti-slip treatments are available for those areas.