When most people start planning a renovation, they think about what they want to change.
A larger kitchen. A better bathroom. More natural light. Better storage. An extension. A new outdoor living area.
But there is another question worth asking before the plans are finalised:
How well does the house actually perform now?
That question has become particularly relevant this year because Queensland homeowners can now access the new Home Energy Rating for Existing Homes program.
The national system expanded in July 2026 to provide energy assessments specifically for existing homes. An accredited assessor can inspect the property and provide information about its thermal performance, energy use, comfort and opportunities for improvement.
For somebody already considering a substantial renovation, that information could be extremely useful.
Instead of discovering after the renovation that the western rooms still become unbearably hot, the roof needs better insulation or the new air conditioner is compensating for problems elsewhere in the building, those issues can potentially be considered while the renovation is still being designed.
What Is a Home Energy Rating for an Existing Home?
Australians may already be familiar with NatHERS energy ratings for new homes.
The Nationwide House Energy Rating Scheme has been used for decades to assess the thermal performance of new residential buildings.
The system has now been expanded so existing houses can also be assessed.
Unlike an assessment of a new house from building plans, an existing-home assessment involves an accredited assessor visiting the property and collecting information about how the home is actually constructed and equipped.
The resulting Home Energy Rating Certificate can include:
- a thermal performance star rating out of 10
- a Home Energy Rating out of 100
- estimated annual energy use
- information about heating and cooling performance
- an indication of comfort without mechanical heating or cooling
- information about major appliances
- solar generation and battery storage where relevant
- areas where the energy performance of the house could potentially be improved
In other words, it provides another way of understanding the house before deciding what to change.
Why Does This Matter When You Are Renovating?
A renovation creates an opportunity that doesn’t exist when you’re simply replacing individual items around the home.
Walls may be opened. Ceilings may be replaced. Windows may be moved. Rooms may be reconfigured. Roof structures may change. New electrical and mechanical systems may be installed.
Once that work is already happening, some improvements can be considerably easier to incorporate than they would be several years later.
For example, imagine renovating a living area only to realise afterwards that most of the afternoon heat is entering through large west-facing windows.
If that problem had been identified during planning, the renovation could potentially have considered glazing, external shading, window placement or another design response at the same time.
The same thinking can apply to insulation, ventilation, air movement and the relationship between indoor and outdoor spaces.
The objective isn’t to turn every renovation into an energy-efficiency project.
It’s to avoid spending significant money renovating a home while overlooking problems that were already there.
A Beautiful Renovation Can Still Be an Uncomfortable House
This is one of the more interesting lessons behind modern energy-efficient design.
Expensive finishes don’t necessarily make a home perform better.
You can install a beautiful stone kitchen, premium appliances and expensive flooring and still have a room that becomes extremely hot every summer afternoon.
Likewise, a new extension can dramatically increase the usable area of a home while also increasing the amount of space that needs to be cooled if orientation, glazing, shading and ventilation aren’t considered early enough.
Queensland’s current residential energy-efficiency guidance identifies design features including insulation, window design, shading, ceiling fans, ventilation and lighter-coloured external surfaces as ways the thermal performance of homes can be improved.
Those principles aren’t only relevant when constructing an entirely new house.
A renovation can provide an opportunity to rethink how parts of an existing home respond to Brisbane’s climate.
What Could You Look at During a Renovation?
The right improvements will depend entirely on the existing house, its orientation, construction and the scope of the renovation.
But there are several areas worth thinking about while the project is being designed.
Insulation
Insulation has a major influence on the transfer of heat through ceilings, roofs and walls.
If a renovation exposes parts of the building that would normally be difficult to access, it can be worth considering whether insulation should be upgraded as part of the work.
Windows and Glazing
Windows bring natural light into a home, but their size, orientation, glazing and exposure to direct sunlight can substantially influence indoor temperatures.
When windows are being replaced or repositioned anyway, there is an opportunity to think beyond appearance alone.
External Shading
Eaves, awnings, verandahs and other forms of external shading can help control direct sun before the heat enters the building.
For some homes, this can be particularly important on windows receiving strong afternoon sun.
Air Movement
Queensland homes can benefit enormously from good natural ventilation and air movement.
Window placement, internal layout, ceiling fans and the way spaces connect can all affect whether breezes can actually move through the house.
Indoor and Outdoor Living
Brisbane’s climate means decks, patios and covered outdoor spaces can become an important part of how a home is used.
A well-planned renovation can consider the relationship between indoor living areas and outdoor spaces rather than treating them as completely separate projects.
Done well, this can improve both usability and the way the home responds to sun, shade and prevailing conditions.
Don’t Just Install a Bigger Air Conditioner
One of the easiest ways to deal with a hot house is simply to add more air conditioning.
Sometimes that is exactly what is needed.
But it is worth asking why the house is becoming so hot in the first place.
If large amounts of heat are entering through an uninsulated roof or exposed glazing, increasing cooling capacity may address the symptom without addressing the underlying problem.
That is where looking at the whole house becomes useful.
According to the Queensland Government’s residential energy-efficiency guidance, better thermal performance reduces the amount of heating and cooling a home requires.
For a homeowner already undertaking substantial building work, improving the building itself and then considering heating and cooling requirements can produce a more complete solution.
Does Your Existing Home Need to Achieve 7 Stars?
This is where there can be some confusion.
Queensland introduced 7-star energy-efficiency requirements for new homes under the Modern Homes standards in 2024.
That does not mean every existing Brisbane home now has to achieve a 7-star rating simply because the owner wants to renovate it.
The new Home Energy Rating for Existing Homes is primarily an information and assessment tool. The certificate produced for an existing home cannot itself be used to demonstrate National Construction Code compliance for a new home or major renovation.
A major renovation, extension or other building work can have separate building approval and energy-efficiency requirements depending on the project.
That is another reason to discuss the scope of substantial renovation work with your builder, designer and building certifier before construction begins rather than assuming the rules that applied to the existing house will automatically apply to everything being added.
Renovating for the Next Brisbane Summer
Energy performance is particularly relevant in Brisbane because much of the conversation about comfort revolves around keeping homes cooler.
The answer isn’t always a single expensive product.
Often it is the combination of decisions made throughout the home: where sunlight enters, whether windows are shaded, how well the roof and walls resist heat, whether air can move through living areas and how much mechanical cooling is required when passive measures aren’t enough.
If you’re already planning to alter the building, it makes sense to consider those things while you still have the opportunity to change them.
Should You Get an Energy Rating Before Renovating?
Not every renovation needs a formal energy assessment.
If you’re replacing a vanity or updating the finishes in a small room, it may provide little practical benefit to that particular project.
But if you’re planning a major renovation, extension or substantial reconfiguration of the home, understanding how the existing building performs can give you another useful layer of information during the design process.
It may help identify opportunities that aren’t immediately visible when the conversation begins with finishes, cabinetry and floor plans.
And that is really the bigger point.
A good renovation shouldn’t only change how a house looks.
Where possible, it should improve how the home works for the people living in it.
Planning a Brisbane Renovation?
At Briswest Renovations, good renovation outcomes start well before construction.
Understanding the existing home, working through the way each space will be used and resolving important design decisions early can help create a renovation that works better long after the building work is finished.
If you’re considering renovating, extending or reconfiguring your Brisbane home, talk to Briswest Renovations about your project and start planning what your home could become.