Extrabuild Logo
Paul - 0407 100 424
Extrabuild Logo
Construction workers working on electrical wiring and interior framing during a home renovation.

Renovations

How to Make Renovations More Energy Efficient

A renovation is the cheapest a home will ever be to make more energy efficient. Once walls are opened and ceilings are exposed, adding proper insulation costs a fraction of what it would to retrofit later, and it’s the same story with windows, ventilation and materials. Four things make the biggest difference: insulation, window type, ventilation design, and the materials chosen for the parts of the house that hold heat in or let it out. Here’s where to focus if sustainability is part of the brief.

Why a Renovation Is the Right Time to Fix Energy Efficiency

Most of the work involved in improving a home’s energy performance happens inside walls, under floors and above ceilings, exactly the areas already exposed during a renovation. Adding insulation to a wall that’s already open costs a lot less than opening it specifically for that purpose later. In New South Wales, renovations and additions valued at $50,000 or more also trigger a BASIX certificate requirement, which assesses the work against energy, water and thermal comfort targets. Smaller cosmetic renovations under that threshold are generally exempt, but once a project crosses it, energy efficiency stops being optional and becomes part of the approval itself.

Insulation: The Single Biggest Lever

Insulation does more for a home’s energy performance than almost any other single upgrade. Roof and ceiling insulation alone can cut heating and cooling costs by 45 percent or more and adding wall insulation during a renovation can bring energy costs down by up to 40 percent on top of that. Older homes, particularly brick veneer built before 1990, often have no wall insulation at all, which makes a renovation the first real opportunity to add it. There are two broad types, bulk insulation (batts made from polyester, glass wool, rock wool or similar) and reflective foil insulation, and the right choice depends on the part of the house being insulated. Look for the R-value on any product, which measures resistance to heat flow. The National Construction Code sets minimum R-values for roofs, walls and floors depending on climate zone, but going above the minimum is often worth it for a renovation where the walls are already open.

Workers applying patterned wallpaper to a wall during indoor home renovation.

Choosing the Right Window Types

Glazing is one of the most effective upgrades available during a renovation, and one of the easiest to overlook. Double or triple glazing reduces heat flow through a window by up to six times compared to single glazing, which matters both for keeping a home cooler in summer and warmer in winter. Frame material matters too; uPVC, timber and thermally broken aluminium all insulate better than standard aluminium frames. Window style affects more than looks awning windows open to a narrow gap and don’t move much air, while sliding or louvre windows open wider and work far better for genuine cross-ventilation. If ventilation matters as much as thermal performance in your climate, it’s worth choosing window styles with that in mind rather than on appearance alone.

Ventilation: Getting Airflow Right

Good ventilation reduces reliance on air conditioning and heating in the first place. Cross-ventilation, air moving in one side of a room and out the other, relies on window placement as much as window type, so it’s worth thinking about during a renovation layout rather than trying to fix afterwards. Roof spaces benefit from ventilation too, allowing summer heat to escape rather than radiating down into living areas, while still sealing well enough to avoid winter heat loss. A renovation is also the right time to check sub-floor ventilation, particularly under older timber floors, since poor airflow underneath a house can lead to trapped moisture and timber rot over time, on top of making the home harder to keep comfortable.

Energy-Saving Materials Worth Considering

Beyond insulation and glazing, a handful of smaller material choices add up. LED lighting throughout uses a fraction of the energy of older fittings and lasts considerably longer. Water-efficient tapware and fixtures reduce both water use and the energy cost of heating that water. Where render, cladding or roofing is being replaced anyway, choosing options with better thermal performance costs little extra over standard products and pays that difference back through lower running costs for the life of the house.

What This Means for a NSW Renovation

For any renovation crossing the $50,000 BASIX threshold, energy efficiency isn’t a nice-to-have added at the end, it’s assessed as part of getting the work approved. Getting the insulation, glazing and ventilation decisions right from the start avoids redesigning parts of the project later to meet a target that could have been built in from the beginning. Extrabuild has been renovating and extending homes across Newcastle and Lake Macquarie for over 30 years and can help work through what makes sense for your specific renovation, both for comfort and for meeting the requirements that apply to it.

FAQs

Does every renovation in NSW need to meet BASIX requirements?

No. BASIX applies to alterations and additions valued at $50,000 or more, and to pools or spas over 40,000 litres. Smaller, cosmetic renovations below that threshold are generally exempt.

Insulation, particularly if walls or ceilings are already being opened up as part of the work. It’s the cheapest time to add it, and roof and ceiling insulation alone can cut heating and cooling costs by 45 percent or more.

Often yes, particularly for west-facing or exposed windows. Double glazing reduces heat flow by up to six times compared to single glazing, which affects comfort and running costs in both summer and winter.

To an extent. Draft sealing, blinds and other minor upgrades help, but insulation and glazing improvements are far cheaper and easier to do properly while walls and windows are already being worked on as part of a larger renovation.

Recent Posts

Load More

What Our Newcastle Clients Say

We’re proud to have completed granny flats and building projects across Newcastle and Lake Macquarie, delivering quality workmanship and exceptional communication.

From our 1st meeting, we knew we would go with Paul. He understood our visions and had alot of great ideas - nothing was ever problem. His builders, Andrew and Bailey, always showed up on time and worked with us to ensure we were all on the same page. The tilers, plumbers, gyprockers and electricians all completed work to high standards. Kathleen was always lovely to chat to and make sure we complied with building requirements. A few unexpected things popped up, which put us over budget, but the end result is amazing. We are very happy with our renovation with Extrabuild.
Nicole G
We chose Paul and his team after seeing Extrabuild undertaking a similar renovation elesewhere in our suburb. We spoke at length with the home owner and felt very comfortable that Paul would deliver a cost effective, stress free solution. Paul delivered this in spades with his team working dilligently and cohesively throughout the project, despite incessant queries from the home owner. His tradesman were extremely courteous and capable - and tidy. Pauls' experience working with certifiers and subcontract trades certainly eased our concerns. Paul also paid close attention to the existing house design and worked hard to match up existing trims where possible, and suggesting amenable options if original materials were no longer available. The result has given the old house a new life and we are very thankful to Extrabuild for their assistance and prefessional appraoch throughout the project.
M Forrest
Paul and his team undertook a large scale renovation on the bottom storey of my house, including changing the garage into living space and adding in master bed, WIR and ensuite. They were great to work with, very professional and helpful and the end result high quality. There were some delays and small errors that got rectified, but I think this is unavoidable to some extent in building and especially with covid delays. I would definitely recommend building with Extrabuild.
E Sideris
After a bad experience prior I decided to get a few quotes. Paul called, inspected the job and discussed the options available to complete the repair. The selling point was that Paul had the knowledge to complete the job which became more apparent after speaking with the other builders. More then happy with the final result which was completed within the quoted timeframe. Would definitely recommend Extrabuild to family and friends.
J Williams
From our very first meeting we knew that Extrabuild was the right fit for us. They looked over our plans, gave us feedback and suggested some extra ideas which we took on board. Even some of the more tricky aspects of the build were solved without too much stress. We can't speak highly enough of Extrabuild and the team who brought our plans to life, they were wonderful and went above & beyond to get things done. We were living in the house throughout the build & they were all very respectful of our privacy, timeframes & even tolerated our crazy dog! They brought our tired little lake house back to life!
J & D DownersCarey Bay
Again, really impressed with Extrabuild and Tyler and TJ have been awesome. So a big thanks to you and the team and hopefully soon we can share a beer in our new home! Tyler has absolutely been a stand out and we're really pleased with his work on everything! I know its not ideal with me living here the entire build so thanks for putting up with me and working around my schedules!
J Hammer
J Hammer
It all looks FABULOUS ....the team are a great bunch of guys - really committed & may I say such polite & caring persons
M Russell
Can highly recommend Extrabuild for really high quality work, cleanliness, punctuality, courtesy and all round great builders. They were able to match our challenging feature architraves and cornices to blend in with the very old part of the house to keep its original charm. They knew exactly how to work with the frame of our old house to make it blend seamlessly with the large new extension. As fussy owners, we are very pleased with the meticulous craftsmanship of Paul, Kathleen and the team at Extrabuild. Happy to show off their work; if anyone is interested, just contact Kathleen.
M CampbellNew Lambton
Thank you for an amazing job renovating our home - your expertise, patience and professionalism.
We totally appreciate and love the work.
Helen & Jonathan
Helen & JonathanHamilton South
We just totally love the extension and it’s made such a huge difference in our entertainment and lifestyle. It’s really beautiful. With the garden taking off with all the rain and sunshine 🌞 the full effect of indoor/outdoor is present. It’s just fabulous being in the kitchen and garden simultaneously.
H BuchananHamilton South
Having watched Paul with his team over the last three years and 3 different builds, I can say he’s a great communicator and a quality employer.
A StarrettNew Lambton
Paul and his team built multiple offices inside my concrete tilt panel warehouse. They are highly professional, on time and on budget. I highly recommend them, the quality of the build and eye for detail is exceptional.
A ThewRedland Bay
Paul & his team undertook termite repairs to our home. This included demolition of some existing walls & frames & replacement of same. Nothing was too much trouble, the service & workmanship was excellent. Price was very affordable. Definitely recommend these guys.
K WilliamsKilaben Bay
We are very happy with everything, especially the floors, they came up great. The new layout is heaps more functional and a lot better for entertaining. Thanks for everything, all your guys were great and whole process was easy and stress free. Great communication from everybody too, made the whole process easy.
D Wood

The Journey to Loving Where You Live Starts Here

Call Paul on 0407 100 424

info@extrabuild.com.au