The glass going into Australian homes is more expensive, more technical and harder to replace than it was five years ago. Site practice has not caught up.
For most of the past decade, a scratched window on a residential site was a nuisance with a known price. The glazier came back, measured up, and a new pane went in. The cost was irritating rather than serious, and the program barely moved.
That is no longer how it works.
The energy efficiency provisions in the National Construction Code 2022 lifted the minimum thermal performance of new homes from six stars to seven under the Nationwide House Energy Rating Scheme. Windows carry a large share of that load. In most climate zones, reaching seven stars means double glazing, Low E coatings, better frames, or some combination of all three. Every state and territory applies the requirement with its own variations, and the pathways are not identical, but the effect on the window schedule has been broadly the same.
The glass in a 2026 home is a different product to the glass in a 2018 home. It costs more, it is made to order, and it cannot always be swapped out for whatever the glazier has on the truck.
That change has quietly moved surface protection from a finishing decision to a risk decision. It is a shift Goop Guys has watched play out from the applicator side of the industry, across thousands of residential sites, since the new provisions came into force.
What seven stars did to the window schedule
NCC 2022 took effect on 1 May 2023, with the energy efficiency provisions commencing from 1 October 2023 and adoption dates varying by jurisdiction. Victoria and Queensland both brought the seven star minimum and the Whole of Home requirement into effect on 1 May 2024.
The detail differs by state, and it matters. New South Wales runs the requirement through BASIX rather than NatHERS. Its thermal performance standard rose on 1 October 2023, from an average of 5.5 to 6 stars up to 7 stars, and it does not apply to homes in climate zones 9, 10 and 11 in north eastern New South Wales, or to apartment buildings up to five storeys.
Queensland allows something different again. Under Queensland Development Code 4.1, the seven star requirement is an energy equivalence standard, and optional credits for a compliant outdoor living area can count towards it. A half star credit applies for a covered outdoor living area meeting the size and insulation requirements, and a full star where it also carries a compliant ceiling fan. A Queensland house can therefore comply with a six star building shell plus a one star outdoor living credit. The credit was expanded to apply state wide on 1 May 2024, and six stars is the minimum baseline shell where credits are used.
The direction of travel is consistent even where the mechanism is not. Building shells got tighter, and glazing carried much of the work. The Queensland government lists high performance glazing among the design features that contribute to the standard.
Builders hoping the next code edition would ease the pressure did not get relief. NCC 2025 was released on 1 May 2026 and made substantial changes to commercial energy efficiency, water management and condensation. It introduced no further residential energy efficiency changes. The seven star requirement stays. Building Ministers also agreed to pause further residential code changes, other than essential safety and quality measures, until around 2029.
For builders, the current glazing reality is not a transition to be waited out. It is the settled position for the rest of the decade.
A modern window is not a pane of glass
Most seven star homes now carry insulating glass units. An IGU is two panes separated by a spacer and a gas fill, sealed together as a single factory assembled component. The Low E coating usually sits on one of the internal faces, protected inside the cavity.
That construction has one consequence that matters enormously on site. A damaged pane cannot be replaced on its own. The whole unit goes.
Every unit is cut to size for its opening and built to a specific thermal specification. There is no stock item to pull off a shelf.
A damaged unit means a new order, a manufacturing slot and a delivery window, all landing at the point in the program where there is the least slack. Single glazed applications still exist, and hard coat Low E products can be specified with the coating exposed. Where that is the case, the coating itself sits directly in the path of everything happening on site.
The part that rarely gets discussed on site
A NatHERS certificate does not simply record that a home reached seven stars. It records the windows that got it there.
The certificate carries a window schedule, and the compliance checklist published alongside it asks whether the installed window meets the substitution tolerances for U value and Solar Heat Gain Coefficient, and the window type, shown on that certificate. Substituted values must be based on the Australian Fenestration Rating Council protocol. A replacement unit is therefore not only a glazing purchase. It is a compliance item.
Putting back something that performs differently to what was modelled becomes a conversation with the assessor and the certifier, not just the supplier. A damaged window at lock up used to be a cost. A damaged window in a seven star home can be a cost, a delay and a compliance question at the same time.
Where the damage actually comes from
Glass is rarely ruined by one dramatic event. It is ruined by accumulation.
Render and mortar splatter. Grinder sparks from an adjacent trade embedding hot metal particles in the surface. Paint overspray. Concrete slurry. And then, most commonly of all, the cleaning that follows, where a blade or an abrasive pad is used to remove what should never have reached the glass in the first place. None of it is malicious. It is the ordinary consequence of many trades working in sequence in a confined space over several months.
Industry guidance published by the Australian Glass and Window Association points to AS/NZS 4667 and AS 4666 as the standards the Australian glass industry uses when assessing visual quality. Inspection is carried out under defined viewing conditions rather than under a work light at close range. That framework is useful when a client raises a mark that sits within tolerance. It offers nothing at all when the damage is real, visible and sitting on a unit that takes weeks to replace.
Surface damage found in the final weeks also has a habit of landing on a defect list, and defect lists have a habit of becoming disputes.
What protection looks like when the glass is the expensive part
This is the position Goop Guys has built over twenty five years, and the reason its work has become more relevant rather than less as glazing specifications have climbed.
Window Goop is a water based peelable coating, rolled on like paint by trained Goop Guys applicators and peeled off when the project is finished. It dries within an hour in the right conditions and protects for up to twelve months, which comfortably covers the working life of most residential builds from glazing installation through to handover. Full product detail is available at the Window Goop product page.
Two details matter for seven star work specifically.
The first is that Window Goop is suitable for soft, hard and Low E coated glass. Coated glass is precisely the surface that conventional protection methods struggle with, because removal often carries more risk than the exposure did. Films and tapes that need a scraper or a solvent to shift introduce a hazard of their own to a coated face.
The second is that Goop peels away without scrapers or harsh chemicals and leaves no residue behind. Cleaning agents in the formula mean the surface underneath comes back clean rather than requiring a second process. On a coated unit, the absence of that cleaning step is the whole point.
Window Goop also covers aluminium joinery, which sits alongside the glass and carries exactly the same finish expectations at handover.
The product is manufactured in Australia on the Sunshine Coast, where Goop Guys has been developing peelable coatings since 2001, and applied through a national franchise network of locally owned operators. That combination of local manufacture and local application is unusual in the protection market, and it is the reason major residential builders have stayed with the business across multiple cycles.
Protection is a sequencing decision
Timing determines whether protection works at all. Goop is applied once glazing is installed and the building is weather tight, ahead of the trades that generate the most airborne mess, and removed immediately before handover. Applied late, it protects nothing. Applied early and removed on time, it covers the entire high risk window. Builders who have moved protection into the program rather than treating it as an optional extra tend to describe the change the same way. It stopped being a cost they justified and became a cost they budgeted.
The gap worth closing
Energy rules changed the value of what sits in the opening. Nobody changed the way sites treat it. The building envelope has become more expensive, more technical and less forgiving, while site practice has largely stayed where it was. Closing that gap is now part of building better rather than a finishing courtesy, and it is one of the few improvements available to a builder without renegotiating a contract or hiring anybody.
The scratch has not changed. What sits behind it has.
THE GOOD BUILDER TAKE
Seven stars did not only raise the specification of the home. It raised the cost of getting the last month of the build wrong.
The window that took a scratch in 2018 was a callback. The same scratch in 2026 can be a made to order unit, a program delay and a certificate conversation running at once. Of every variable in that equation, protection is the cheapest and the most controllable.
Common questions
Because the glass itself is a higher specification product. Meeting the seven star standard introduced by NCC 2022 commonly requires double glazing, Low E coatings or both, depending on climate zone and jurisdiction. Queensland offers an alternative pathway using outdoor living area credits, and New South Wales runs its own BASIX settings, so the pressure on glazing is not uniform across the country. Where high performance units are specified, they cost more to buy, are built to order rather than held in stock, and take longer to obtain. The replacement also has to match the thermal performance recorded on the NatHERS certificate, which adds a compliance step that did not exist with basic single glazing.
No. An insulating glass unit is sealed at the factory, with two panes bonded to a spacer and a gas fill between them. Damage to either pane means the complete unit is replaced. This is the single biggest reason the cost of glass damage has risen on residential sites.
It can. The NatHERS certificate includes a window schedule, and the accompanying compliance checklist asks whether the installed window meets the substitution tolerances for U value and Solar Heat Gain Coefficient, along with the window type, shown on that certificate. Substituted values must be based on the Australian Fenestration Rating Council protocol. A replacement that performs differently to the modelled window is a matter for the assessor and the certifier.
Yes. Window Goop from Goop Guys is suitable for soft, hard and Low E coated glass. It is applied as a liquid by trained applicators and peeled off at the end of the project, so no scraper or solvent touches the coated surface. This matters more with coated glass than with plain float glass, because removal methods are often what causes the damage.
Up to twelve months. It dries within an hour in the right conditions, then holds through the construction phase and peels away without residue. For most residential builds, a single application covers the period between glazing installation and handover.
Goop Guys applies temporary surface protection to windows, benchtops, baths and floors through a national network of locally owned franchises. More information is available at goopguys.com.
For more coverage built for Australian builders, visit thegoodbuilder.com.au, subscribe to the weekly newsletter, or listen to The Good Builder Podcast.
Information current as at 13 August 2026.
This article is partner content produced in association with Goop Guys. It contains general information only and does not take into account the circumstances of any particular project or business. Regulatory requirements, including National Construction Code adoption dates, vary between states and territories and change over time. Readers should confirm current requirements with their certifier, energy assessor or relevant state building authority.
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