Home Performance
A comfortable home feels stable, calm and easy to live in. It does not swing sharply between hot and cold, rely constantly on mechanical correction or leave some rooms feeling uncomfortable while others feel fine.
A comfortable home is shaped by the relationship between climate, orientation, glazing, shading, insulation, air movement and building fabric. NatHERS helps assess how much heating and cooling a home may need to stay comfortable in its local climate. The aim is not only a better star rating, but a home that feels more stable and liveable throughout the year.
A comfortable home is not necessarily one that is always the same temperature. It is a home that responds gently to changing weather. It avoids rapid overheating, excessive heat loss, draughty rooms and strong temperature differences between spaces.
This kind of stability comes from the building itself. The roof, walls, floors, windows, doors, insulation, shading and air leakage control all affect how quickly heat enters, leaves or moves through the home.
When the building fabric performs well, heating and cooling systems do not need to work as hard to make the home feel comfortable.
NatHERS estimates how much heating and cooling energy a home may need to maintain comfortable indoor conditions in its local climate. The star rating is based on the thermal performance of the design, not on household behaviour or energy bills.
This is why NatHERS is closely connected to comfort. A higher star rating generally means the home is predicted to need less heating and cooling to stay comfortable, because the building fabric is doing more of the work.
For more detail, see our guide to why thermal comfort matters more than energy bills.
Comfort is not created by one product.
It comes from the way the whole home responds to climate, sun, shade, heat, cold and everyday use.
Windows shape comfort because they connect the home to light, views, heat gain and heat loss. A room with large unshaded glazing may feel bright and open, but it can also overheat or feel uncomfortable near the glass.
Good window design balances daylight, views, orientation, glazing performance, frame type and shading. A comfortable home does not simply maximise glass. It places and specifies windows carefully so they support the room rather than overwhelm it.
For more detail, see our guide to how window design affects NatHERS ratings.
External shading can make a major difference to comfort because it helps control solar heat before it enters the home. This is especially important for windows exposed to strong afternoon sun or large areas of summer solar gain.
The best shading strategy depends on orientation and climate. A north facing window, east facing window and west facing window may each need a different response. Good shading supports comfort without unnecessarily blocking useful daylight or winter sun.
For more detail, see our guide to shading and solar heat gain.
• Stable indoor temperatures across the day and night
• Well placed and well shaded windows
• Suitable insulation in ceilings, walls, roofs and floors
• Reduced draughts and controlled air movement
• Building materials that suit the climate and design
• A layout that responds to sun, shade, wind and daily use
Insulation helps slow the movement of heat through the home’s roof, ceiling, walls and floors. This can help keep warmth inside during cold weather and reduce heat entering during hot weather.
Comfort improves when rooms do not lose heat too quickly at night or gain heat too quickly during the day. Good insulation supports this stability, especially when it is installed in the right locations and coordinated with the rest of the building fabric.
For more detail, see our guide to how insulation affects NatHERS ratings.
Air movement can help comfort when it is planned, but uncontrolled draughts can make a home feel cold, uneven or difficult to heat and cool. A comfortable home manages air movement rather than leaving it to gaps and leakage.
This does not mean sealing a home without ventilation. Healthy homes still need fresh air. The difference is that ventilation should be deliberate, while air leakage through gaps and poorly sealed construction is usually uncontrolled.
For more detail, see our guide to air leakage and home performance.
A comfortable home is not simply a home with a larger air conditioner.
Mechanical systems can help, but the building fabric determines how much correction the home needs in the first place.
Thermal mass can help a home moderate temperature changes by absorbing, storing and releasing heat. Concrete floors, masonry and some other dense materials can support comfort when they are used carefully.
Thermal mass works best when it is coordinated with climate, solar access and shading. If it receives useful winter sun and is protected from unwanted summer heat, it can support stability. If it stores too much unwanted heat, it can work against comfort.
For more detail, see our guide to thermal mass and NatHERS performance.
A comfortable home in one part of Australia may need a different design response from a comfortable home somewhere else. Hot humid, hot dry, cool temperate, alpine, coastal and inland climates all create different comfort priorities.
In warmer climates, comfort may depend heavily on shading, reduced heat gain, roof colour and air movement. In cooler climates, comfort may depend more on heat retention, glazing performance, insulation and draught control. Mixed climates often need careful balance across the seasons.
For more detail, see our guide to building for different Australian climates.
A comfortable home often needs less heating and cooling because it is less exposed to outdoor extremes. This is where comfort and energy efficiency overlap. Better building fabric can reduce the energy needed to maintain liveable conditions.
However, comfort should not be reduced to bills alone. A home should not require occupants to tolerate extreme conditions just to keep energy use low. True performance is a balance between comfort, efficiency and usability.
NatHERS supports this balance by assessing the thermal behaviour of the home before it is built.
Residential energy compliance often focuses on documentation, star ratings and approval pathways. But the underlying purpose is practical: homes should be able to provide better thermal comfort with less heating and cooling demand.
For many new homes, this may connect with 7 Star Rating, Whole of Home and state based pathways such as BASIX in NSW.
The best compliance outcome is one that supports the lived quality of the home, not only the paperwork required for approval.
Designing for comfort means considering the home as a complete system. Windows, shading, insulation, roof colour, floor construction, air movement and thermal mass need to work together.
A design that performs well in one climate may need adjustment in another. A comfortable Australian home responds to its local conditions rather than relying on generic assumptions or late product upgrades.
The strongest homes feel comfortable because performance is embedded in the design from the beginning.
Certified Energy provides NatHERS assessments for new homes, townhouses and multi residential projects across Australia. Our team can model the home and help project teams understand how the design is likely to perform thermally in its local climate.
Where needed, we can help identify how comfort and rating outcomes are affected by glazing, shading, insulation, roof colour, floor construction, thermal mass, air leakage assumptions and climate zone. We can also help connect NatHERS with related requirements such as NatHERS, BASIX, 7 Star Rating and Whole of Home.
For the broader assessment framework, visit our NatHERS Knowledge Hub.
A comfortable home has stable indoor temperatures, good insulation, suitable glazing, effective shading, controlled air movement and a building fabric that responds well to the local climate.
Does NatHERS help measure home comfort?NatHERS estimates how much heating and cooling a home may need to maintain comfortable indoor conditions in its local climate. It is a thermal performance rating, not a household energy bill prediction.
Can a home be comfortable without using much heating and cooling?Yes. A well designed home can often stay comfortable with less heating and cooling because its building fabric, orientation, glazing, shading and insulation reduce temperature extremes.
Is comfort only about temperature?No. Comfort is also affected by draughts, radiant heat from windows, humidity, air movement, temperature differences between rooms and how quickly the home heats up or cools down.
What design features improve comfort?Useful design features include suitable orientation, well placed windows, external shading, good insulation, controlled air leakage, appropriate thermal mass, roof colour selection and construction details suited to the climate.