The cheapest sensible way to double glaze a Narre Warren house
Straight answer: $10,500 to $16,000 in 2026 for retrofit secondary glazing across a typical 14 opening house, against $18,500 to $27,000 for full aluminium replacement and $33,000 to $48,000 for uPVC or thermally broken frames with acoustic and solar control glass where it matters. If the budget is under $6,000, do not spread it thin: glaze the three coldest rooms properly and leave the rest single glazed until next year.
Narre Warren houses are mostly 1985 to 2005 brick veneer with single glazed aluminium sliders, and the honest position is that double glazing all of it at once is a large amount of money for a comfort improvement rather than a financial return. Nobody should pretend otherwise. What follows is how to spend the least and still end up with something that works in twenty years, which tiers are real, and the four places where saving $300 today costs $1,400 later. Every figure is a 2026 supplied and installed rate for this area, GST included, and the full rate card sits on the pricing page.
Budget, mid and premium on a typical Narre Warren house
The house below is the one we quote most often here: single storey brick veneer, four bedrooms, fourteen window openings plus one sliding door, about 26 square metres of glass in total, built between 1990 and 2005 with builder standard single glazed aluminium. All three tiers include measure, supply, install, silicone and basic make good. All three assume the whole house is ordered at once, which is where the volume discount comes from.
| Tier | Real 2026 price | What you get | What you give up | Who should pick it |
|---|---|---|---|---|
| Budget: retrofit secondary glazing | $10,500 - $16,000 ($580 to $2,400 per opening before discount) | A second pane sealed onto the frames you already own. Roughly 70 to 80 per cent of the thermal benefit of replacement and most of the condensation fix. Fully reversible, no permit, no make good, install in 2 to 3 days. | The old frames and their draughts stay. Sightlines get chunkier. Acrylic panels scratch and need replacing at 10 to 15 years. No change at all to how the house looks or values from the street. | Renters with a landlord’s written consent, landlords, anyone under $16,000, and heritage or rendered facades you do not want disturbed. |
| Mid: full replacement, standard aluminium | $18,500 - $27,000 ($880 to $3,800 per opening before discount) | New frames, new hardware, new seals, 4/12/4 clear Low-E argon units on a warm edge spacer, whole of window U-value around 2.4 to 2.8. Draughts gone, condensation gone in most rooms, 25 to 35 year frame life. | No thermal break in the frame, so on a 3 degree morning you can still get a little condensation on the frame itself even though the glass is dry. Reveal and architrave make good is extra on some openings. | Owner occupiers staying 5 years or more who want it done once, and anyone whose existing frames are corroded, jammed or leaking. |
| Premium: uPVC or thermally broken aluminium | $33,000 - $48,000 ($1,200 to $4,200 per opening before discount) | Whole of window U-value 1.4 to 2.0, toned solar control glass on the west, an asymmetric acoustic build in the two bedrooms nearest the road, multipoint locking, and no cold frame surface anywhere in the house. | Twelve to eighteen thousand dollars more than the mid tier, and a payback measured in decades rather than years. uPVC frames are visually chunkier than slim aluminium on large spans. | Forever homes, west facing living areas that are unbearable in February, houses on the Princes Highway or near the rail corridor, and anyone chasing a NatHERS star rating for a renovation. |
Indicative 2026 rates, GST inclusive, for Narre Warren, Narre Warren South, Fountain Gate and Berwick. Your house will differ: a firm price needs a measure. The glass specification behind these tiers is explained on the glass makeup page.
Our recommendation: if you own the house and plan to stay, the mid tier with two premium upgrades bought individually beats the premium tier everywhere. Take the standard aluminium replacement at $18,500 to $27,000, then spend about $700 on toned solar control glass for the three west facing openings and about $900 on an acoustic build for the front bedroom. That is roughly $20,000 to $28,600 and it delivers most of what the $40,000 option delivers, because the last 20 per cent of performance is always the expensive 20 per cent.
Where you can safely save money
Six of these are real savings that cost you nothing in performance. We suggest them to customers before they ask.
- Order the whole house, stage the install. Past about ten openings the per window rate drops 15 to 25 per cent because the measure, the freight from the fabricator and the crew mobilisation are shared across the job. If cash flow is the problem, lock in the whole house price and split the install into two visits three to six months apart, so you keep the discount and spread the payment. Two separate orders lose the discount twice.
- Keep frames that are sound. Roughly 40 per cent of a replacement quote is the frame and the hardware. If your timber frames are solid and square, a retrofit unit dropped into them is $880 to $1,400 per medium opening instead of $1,500 to $2,400. Poke the bottom of every sill with a screwdriver first: if it goes in more than a couple of millimetres, that frame is not a candidate. The method is on our retrofit page.
- Stay on standard sizes. Fabricators cut from stock lengths, and an opening that lands within a standard module costs less than one needing a custom extrusion run. If you are also rebuilding a reveal or moving a window, ask what the nearest standard size is before you set the new opening. It can be a $200 to $400 per window difference.
- Do the preparation yourself. Taking down curtains, blinds, tracks and pelmets, unscrewing security screens, clearing 1.2 metres in front of every window inside and out, and cutting back the shrubs under the sills is two hours of your Saturday and takes real hours off the install. Some crews charge for it, all crews are slowed by it. The full list is on our installation day page.
- Book outside the panic season. Enquiries here spike in the fortnight after the first genuinely cold morning in May and again in the first 40 degree week of summer. Lead times stretch from three or four weeks to eight or ten, and nobody is discounting. February to April and September to November are the quiet windows, and that is when a crew has room to move on price. See best time of year to double glaze.
- Skip the upgrades that do nothing on your house. Argon in a 0.3 square metre fixed toilet window is $80 you will never feel. Toned solar control glass on a shaded south facing window makes the room dim for zero thermal gain. Acoustic glass in the back bedroom of a house whose noise comes from the front is $400 wasted. Specify room by room, not house wide.
- Paint your own reveals. If the quote includes making good and painting internal reveals and architraves at $120 to $280 per opening, doing that yourself on fourteen openings is $1,700 to $3,900 back in your pocket for a weekend with a caulking gun and a litre of low sheen.
Want the three tiers priced against your own windows?
We measure the house once and quote all three tiers on the same sheet, so you can see exactly what the extra money buys. Free, and it takes about an hour.
Where saving money gets paid for twice
These are the false economies. Each one saves real money on the day and each one has cost a Narre Warren homeowner considerably more within a decade.
- Dropping the thermal break to save $150 to $350 a window. A non broken aluminium frame conducts cold straight through, so on a damp 3 degree morning you get water running down the frame of a window whose glass is perfectly dry. Customers assume the window has failed. It has not, it was under specified. On a house with high indoor humidity this is the single most regretted saving.
- Accepting an aluminium spacer and a 6mm cavity. Saves about $200 a window, gives back a visible condensation band along the bottom edge and shortens the sealed unit life from 20 to 25 years down to 8 to 12. Replacing a fogged unit later is $380 to $850 per pane, so on fourteen windows you have swapped a $2,800 saving for a $6,000 bill.
- Buying units online and finding your own installer. Imported sealed units without an AS 2047 compliance label are cheap for a reason, and if the unit fogs in year four you are chasing a warranty across an ocean. The installer will not warrant glass they did not supply, and the supplier will not warrant an install they did not do. You end up holding both halves of the problem.
- Glazing into rotten or racked frames. A retrofit unit is only as good as what holds it. Putting a 25 year sealed unit into a sill that has three years left means paying twice for the same window, and the second time includes removing the unit you just bought.
- Skipping the perimeter seal and flashing. A window is a hole in a wall. If the gap between the frame and the brickwork is not foamed, flashed and sealed properly, the draught you paid to remove walks straight around the outside of your new window and water gets into the wall cavity behind the render. This is not visible for two or three winters.
- Taking a cash job with no paperwork. No written contract, no ABN on the invoice and no insurance certificate means no warranty you can actually enforce, and it puts you outside the protections described on our warranty page. The discount is never worth it.
What a suspiciously low quote is leaving out
When one quote comes in $5,000 under the others, it is almost never because that business is cleverer. It is because the scope is smaller. Price the following back in and compare again, line for line.
| Commonly omitted item | What it costs to add back | Why it gets left out |
|---|---|---|
| Reveal, architrave and plaster make good | $120 - $280 per opening | It is the messiest part and it is easy to describe as "by others" |
| Removal and tip disposal of old frames and glass | $180 - $450 per house | Landfill levies are real money and glass is heavy |
| Grade A safety glass to doors and low panes | $90 - $220 per pane | It is a code requirement, not an option, so it should never be omitted |
| Flyscreens on opening sashes | $90 - $160 each | Assumed you will reuse the old ones, which never fit new frames |
| Access equipment for a second storey | $600 - $1,600 per job | Quoted from photos without anyone visiting the site |
| External render or brick make good | $150 - $400 per opening | Only shows up once the old frame is out |
| New locks, keyed hardware and restrictors | $40 - $120 per sash | Base hardware is quoted, upgrades are not mentioned |
Add the applicable lines to the low quote before you compare. On a fourteen opening house these items commonly total $3,500 to $6,500.
Two other things to check on any quote. Is it fixed or does it carry a provisional sum that can move after the frames come out? And does it name the glass makeup, the frame system and the whole of window U-value, or does it just say "double glazed"? A quote that will not put those numbers on paper is not a quote you can compare with anything.
Victorian rebates, programs and rules that change the maths
Be careful here, because this is the part of the conversation where the most nonsense gets talked. As at 2026 there is no Victorian rebate that simply pays a share of the cost of double glazing a home, and there is no free double glazing scheme. If a salesperson says there is, ask them to name the program and the activity in writing.
- Victorian Energy Upgrades. This is the state scheme that creates discounts on eligible energy saving activities through accredited providers, and residential draught proofing and weather sealing around windows and doors has been part of it. The activity list is revised from time to time, so the useful question is not "is there a rebate" but "which VEU activity applies to my job, and will the discount appear as a named line on my quote". A discount you cannot see on the invoice is not a discount.
- Energy upgrade loans. Several lenders offer discounted green home upgrade loans backed by federal clean energy funding, and double glazing is generally an eligible upgrade. That is cheaper money, not free money, and it only makes sense if you were going to do the work anyway.
- The 7 star requirement. Victoria has adopted the current National Construction Code energy provisions, so a new home or a substantial renovation has to reach a NatHERS star target and a whole of home energy target. If you are extending or rebuilding anyway, high performance glazing is no longer optional and it should already be inside the builder’s price rather than being sold to you as an upgrade.
- Rental properties. Victoria has been steadily tightening the rental minimum standards and draught sealing sits inside that direction of travel. Double glazing is not required. Check the current standards with Consumer Affairs Victoria before you spend money on the strength of a rule you half remember, and talk to your accountant about whether the work is a deductible repair or a capital works item, because the answer changes the real cost by thousands.
- Permits. Replacing a window like for like in the existing opening generally needs no building permit. Widening an opening, altering a lintel or cutting a new hole is structural and does, typically $700 to $1,800 through a registered building surveyor. Check with the City of Casey if your property carries a heritage or neighbourhood character overlay, which parts of old Berwick do.
Two jobs to do before you spend a dollar on glass
This is the honest constraint on the whole page, and we say it on the driveway at most measures. If your ceiling insulation is thin, patchy or missing, and your doors and windows leak air, then glazing is not the best use of the next $4,000.
- Ceiling insulation. Topping a typical Narre Warren ceiling up to a modern level runs about $1,800 to $3,500. More heat leaves through a poorly insulated ceiling than through the windows in most single storey brick veneers here, and it is a fraction of the cost.
- Draught sealing. Door seals, window seals, sealing the exhaust fans and the chimney, and closing the gaps around downlights and skirtings costs about $400 to $900 and can be felt the same night.
Do those two first, live through one winter, then decide how much glazing you actually need. Plenty of people find they only need the three coldest rooms after that, which turns a $22,000 project into a $5,500 one. We will still be here, and we would rather quote you the smaller job honestly than the bigger job once. If you want to check how much glass you are dealing with in the first place, the glass area estimator will size it in about two minutes, and the Narre Warren service page covers how we work locally.
Get all three tiers priced on one sheet
Tell us the house and the budget, and we will come out, measure, and quote budget, mid and premium side by side, back to you within 7 days.