Keep Your Existing Frames
Retrofit installs into your current timber or aluminium — no structural work, no demolition, no mess.

From $495/m² — Keep your existing timber or aluminium. Double the performance.
Why Retrofit
Retrofit installs into your current timber or aluminium — no structural work, no demolition, no mess.
Most Melbourne homes are completed in a single visit. You're back to normal by sundown.
Half the cost of full window replacement with equivalent thermal and acoustic performance.
Cut heating and cooling bills year-round. The glass upgrade that actually pays for itself.
Glass and workmanship guaranteed in writing — not just a verbal promise.
We service all suburbs from the CBD to the Mornington Peninsula. No travel surcharges.
Four performance tiers. Every budget. Transparent pricing — no surprises at invoice.
Reliable thermal and acoustic baseline for most Melbourne homes.
Best for: Most homes, balanced performance
Learn moreMaximum thermal control for west-facing or solar-heavy rooms.
Best for: Hot rooms, energy bill reduction
Learn moreSpecialist glass for traffic, planes, and neighbour noise.
Best for: Busy roads, flight paths, party walls
Learn morePremium thermal and acoustic performance for full home comfort.
Best for: Maximum energy efficiency, cold climates
Learn moreFour steps from enquiry to a warmer, quieter home.

Enter your window dimensions into our Instant Estimate Tool. Get a transparent price in 60 seconds — no site visit required.

A King technician reviews your submission. You receive an itemised quote within 24 hours. No vague estimates, no pressure.

Our crew fits new double-glazed units directly into your existing frames. One day. No structural work. No mess.

Lower energy bills from day one. Quieter rooms. Government rebate paperwork handled by us.
Retrofit vs The Alternatives
Retrofit delivers full-replacement performance at half the cost and none of the mess.
| Feature | KingRetrofit | Full Replacement | Secondary Glazing |
|---|---|---|---|
| Typical cost | From $495/m² | From $1,200/m² | From $350/m² |
| Installation time | 1 day | 3–7 days | 1–2 days |
| Frame disruption | None | Full demolition | None |
| Heritage / period windows | |||
| Thermal performance (U-value) | 1.1–2.0 W/m²K | 1.1–2.0 W/m²K | 2.5+ W/m²K |
| Acoustic performance (Rw) | 30–52 dB | 30–52 dB | 20–28 dB |
| VEU rebate eligible | |||
| Warranty | 10 years | 5–10 years | 2–5 years |
| Council approval usually required |
* Prices are indicative and market-dependent. King Retrofit prices guaranteed at time of quote.
Real Results
Measured results from Melbourne homes. Not marketing copy.




Bedroom temp at 11 pm (summer)
−7° without extra air con
Quarterly energy bill
−41% average saving
Street noise (Rw measurement)
Halved perceived loudness
Window condensation
Warm inner pane eliminates dew point
Results vary by home size, orientation, and glass type selected. Data from King customer surveys 2024–2025.
Customer Reviews
Every review is from a verified retrofit customer.
5.0 · 18 Reviews · Google
Heating bill dropped noticeably in the first month. Our Victorian terrace was a nightmare to heat — now the lounge actually holds temperature overnight. The retrofit took one day and the crew left the place spotless.

Sarah M.
Fitzroy North · Google
We live 40 metres from a tram stop. The acoustic difference after the laminated glass went in was honestly shocking. I didn't expect it to be that dramatic. Wish we'd done it ten years ago.

David K.
Richmond · Google
Got three quotes. King came in $2,100 less than the next cheapest and finished the job in a single day. No upselling, no vague pricing — the final invoice matched the online estimate exactly.
Jen & Tom R.
Balwyn · Google
Was sceptical about retrofit vs full replacement. A friend told me to just do the full windows. Glad I ignored him. You cannot tell the difference visually, and the performance specs are identical.
Michael A.
St Kilda · Google
West-facing bedroom was genuinely unusable in summer — 34°C at 9pm. Tinted Low-E glass has fixed it completely. Air con barely runs now. The estimate tool online gave me the exact price before anyone even came out.
Anna P.
Camberwell · Google
Used the instant estimate tool to budget before committing. No sales call, no pressure. The price they quoted was the price I paid. That kind of transparency is rare in the trades.
Chris L.
Brighton · Google
Our bedroom faces Sydney Road. Friday and Saturday nights were unusable — we were wearing earplugs to sleep. The acoustic laminated glass has completely changed the situation. The tram noise that used to wake us at 6 am is now barely audible. I genuinely did not think glass could make that much difference.
Marcus & Priya N.
Brunswick · Google
Flight path noise was the main reason we almost moved. A friend suggested acoustic glazing as a last resort before we listed the house. We're not moving. The difference in the front rooms is night and day — my daughter actually sleeps through now. Worth every cent.
Helen C.
Port Melbourne · Google
Our gas bills were brutal every winter — the old single-pane windows were just radiating cold into the rooms. We went with Low-E double glazing throughout. First winter after: $380 less on gas over the quarter. The house holds heat in a way it never did before. We wished we'd done it when we bought the place.
Rob & Diane F.
Glen Waverley · Google
I was skeptical about the energy saving claims — they always sound too good. But the condensation alone proved the point: zero condensation on the inner pane since installation, where before it was streaming every winter morning. The heating runs half as often. The numbers are real.
Yasmin T.
Northcote · Google
We were told by two other glaziers that we'd need council approval and a heritage consultant before touching the windows. King told us that a glass-only retrofit is permit-exempt — kept the frames, just replaced the glass. They were right. No permit, no consultant, done in one day. The house looks exactly the same from the street, and the draughts are completely gone.
Oliver & Kate B.
Carlton · Google
Our Victorian terrace is on the Heritage Overlay and I was nervous about any window work. King assessed the frames, confirmed the retrofit was permit-free, and did the whole house in a day. The original sash windows still look original — you'd never know the glass had changed. Warmer, quieter, no heritage headache.
Fiona M.
Fitzroy · Google
Woke up to a burglary at 3am — back door glass completely smashed. Called King at 6am, glazier was here by 7:45am, property secured before we left for work. Didn't expect anyone to show up that fast. They boarded it properly, not just cardboard, and came back two days later with the permanent glass. Exactly what you need when you're in shock.
Paul & Sandra O.
Hawthorn · Google
Tenant called me at 7pm on a Friday — kitchen window smashed. King had a glazier there by 9pm and replaced the glass permanently on the same visit. No board-up, no return trip, no landlord nightmare over the weekend. I've used them for three emergency jobs now and the response is always the same.
Rental Manager — South Yarra
South Yarra · Google
Storm took out my lounge window at 11pm on a Wednesday. I expected to be told someone would come in the morning. King had a glazier here within the hour. He cleaned up the glass, boarded the frame properly, and the permanent replacement was fitted two days later. Professional job, not a handyman with a piece of wood.
Diane K.
Footscray · Google
We manage 14 strata buildings across Melbourne. King handles all our glazing — routine replacements, double glazing retrofits on older blocks, and emergency call-outs. The invoicing is clean, the pricing is consistent, and they show up when they say they will. That last part is rarer than it should be.
James R. — Strata Manager
South Melbourne · Google
Needed a full shopfront glass installation done over a weekend so we could open Monday. King confirmed the timeline, showed up Saturday morning, and were done by Sunday afternoon. The glass is immaculate — not a mark on it. Every trade we brought in for the fitout delivered late except these guys.
Natalie W. — Retail Fitout
Collingwood · Google
Used King on a 12-unit apartment project — double glazing throughout plus frameless balustrades on the upper levels. Scope was substantial and they handled it without the project management headaches I've had with other glaziers. Itemised quotes, predictable scheduling, zero defects at handover. We're using them on the next project.
Tom B. — Property Developer
Richmond · Google
FAQ
Everything Melbourne homeowners ask before booking.
Retrofit double glazing replaces only the glass unit inside your existing window frame — the timber or aluminium surround stays in place. A glazier removes the original single-pane glass and installs a sealed, factory-made double-glazed unit (two panes of glass separated by an inert gas cavity) in its place. You get the full thermal and acoustic benefit of double glazing without touching the frame, architraves, or surrounding wall.
Most standard timber and aluminium frames in Melbourne homes are suitable, provided the rebate (the groove the glass sits in) is deep enough to accept a double-glazed unit — typically 28–36 mm. Casement, awning, sliding, and fixed windows are all compatible. Very thin heritage sashes may need a slightly thinner unit; our technician confirms suitability at measure-up.
A standard Melbourne home with 8–14 windows is typically completed in one day. We remove the old glass, install the new double-glazed units, re-seal, and clean up before we leave. There is no structural work and no plaster damage.
No. The frame stays identical. From street level — and from inside — retrofitted windows are visually indistinguishable from the originals. The only change visible if you look closely is a small aluminium or warm-edge spacer bar around the glass perimeter, which is recessed into the rebate.
Yes. Retrofit double glazing qualifies for the Victorian Energy Upgrades (VEU) program. Depending on your home's heating zone and the glass specification chosen, the rebate can offset $300–$900 per typical home. We handle the paperwork — you just sign.
Identically, glass for glass. Both retrofit and full-replacement windows use the same factory-sealed double-glazed units. The U-value and SHGC of the glass — which determine thermal performance — are set by the glass specification, not by the frame type. You get the same Low-E coating, the same gas fill, the same spacer, and the same performance at roughly half the price.
U-value depends on the glass tier you choose: standard clear double glazing achieves around 2.0 W/m²K; Low-E double glazing reaches 1.1–1.4 W/m²K; triple glazing can reach 0.8 W/m²K. Acoustic Rw ratings range from 32 dB (clear double) to 52 dB (laminated acoustic). Our glass options page shows the full specs for each tier.
Yes — this is one of retrofit's main advantages over full replacement. Because the original frame is preserved, most heritage overlay overlays and council requirements are unaffected. We regularly work on Victorian and Edwardian timber sashes across inner Melbourne suburbs. If your property is on the Heritage Overlay we recommend confirming with your council first, but in almost all cases retrofit glazing is permitted without a planning permit.
Objectively: our standard laminated acoustic unit achieves Rw 38, cutting perceived loudness by roughly half compared to a single-pane window (Rw 26). In practice, customers near tram lines or arterial roads describe the difference as "dramatic" — the low-frequency rumble that travels through single glazing is the first thing to disappear. Acoustic laminated glass performs significantly better than standard double glazing for noise.
King provides a 10-year written warranty covering the sealed glass unit (against seal failure and fogging), the installation workmanship, and all associated hardware. The warranty is transferable to a new owner if you sell your home. Glass breakage is not covered — that is covered under your building insurance.
Enter your window dimensions and get a transparent, itemised price in 60 seconds. No sales calls. No site visit required.
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✓ Price locked at quote
✓ 10-year warranty
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