By Penot Double Glazing
The internet has a lot of double glazing content. Most of it is generic. This article answers the 30 questions Perth homeowners actually ask, with the specific 2026 numbers and the honest framing. Drawn from AGWA, AS standards, NCC 2022, Bureau of Meteorology Perth data, and confirmed double glazing Perth market pricing.
The questions cluster into six topic areas: cost, energy, noise, product, process and comparison. Use the table of contents in your browser or just scroll. Every answer cites a source or notes where the evidence is weak.
Cost Questions
What Does Double Glazing Cost in Perth in 2026?
A single double glazed aluminium window in Perth runs $450 to $2,200 supply only depending on size and spec. A standard 1500 x 1500 mm sliding window in thermally broken aluminium with low-e glass runs $1,100 to $1,700 supply only. A whole-house project of 10 to 15 windows plus 1 to 2 doors runs $24,000 to $57,000 supply and install for thermally broken aluminium. Source: Penot Double Glazing cost guide for Perth.
What Affects the Price of Double Glazing More than Anything Else?
Window size first, then glass spec, then frame spec, then hardware and finish. A 2400 x 1800 mm fixed picture window is roughly four times the cost of a 1200 x 1200 mm awning of the same spec. Within size, the biggest spec upgrade is the move from clear standard double glazed to solar-control low-e, which adds $200 to $500 per window.
Is the Cheapest Double Glazing Quote Ever Worth Taking?
Rarely. Two quotes that look 30 to 60 per cent apart usually have different glass and frame specs. The cheapest quote often uses standard non-thermally-broken aluminium frames with clear double glazed units, which underperforms thermally broken aluminium with low-e on a Perth west-facing room. Match specs before comparing prices. Our choosing a double glazing company Perth guide covers what separates good suppliers from average ones.
How Much Does a Double Glazed Sliding Door Cost in Perth?
Penot supplies thermally broken aluminium as standard. Door pricing depends on the opening size, number of panels, glass, hardware, finish and installation scope. Request an itemised quote for your opening so that supply-only and installed prices can be compared on the same basis.
How Much More Does Triple Glazing Cost than Double Glazing?
Triple glazing adds a third pane and may require different frames and hardware. Ask for a like-for-like quote against double glazing, with the performance ratings and installation scope stated. See our triple glazed windows cost guide.
Energy Questions
How Much Does Double Glazing Reduce Energy Bills in a Perth Home?
Energy savings depend on the complete window, the building, shading and how heating and cooling are used.
What Is the Best Glass for Summer Heat in Perth?
Solar-control low-e glass can help limit incoming solar heat. Compare the solar heat gain coefficient (SHGC) for the quoted window and consider its orientation and shading. Read our guide to double glazing and summer comfort.
What Does SHGC Mean?
Solar Heat Gain Coefficient. A number from 0 to 1 that measures how much of the sun’s radiant energy passes through the glass. Lower SHGC = less heat enters. For Perth’s cooling-dominant climate (BCA Climate Zone 5), SHGC matters more than U-value for west-facing and unshaded north-facing windows. Our U-values, SHGC and window energy ratings in WA guide explains in detail.
What Does U-value Mean?
A measure of how quickly heat conducts through the window assembly, in watts per square metre per degree Kelvin (W/m²K). Lower U-value = better insulation. Standard single glazed aluminium runs around 5.5 to 6.6 Uw. Thermally broken aluminium with low-e double glazed sits at 1.8 to 2.5 Uw. Triple glazed best spec reaches 1.0 to 1.4 Uw.
What’s a Thermal Break in an Aluminium Frame?
A polyamide (nylon) strip or foam insert that interrupts the conduction path through an aluminium frame between the inside and outside faces. Standard aluminium frames have a U-value around 6.6 W/m²K. Thermally broken aluminium drops to around 2.2 W/m²K. The thermal break also prevents winter condensation on the internal frame face.
Noise Questions
How Much Noise Does Double Glazing Block?
Acoustic performance depends on the complete window specification and installation. Ask for test data for the configuration being quoted.
What Is the Best Glass for Road Noise in Perth?
Acoustic laminated double glazed unit. The acoustic PVB interlayer in the outer laminated pane absorbs sound energy across a wider frequency range than standard PVB. Typical Rw values: 37 to 42, with some configurations reaching 45 with thicker outer panes. For properties within 200 to 300 metres of Kwinana Freeway, Mitchell Freeway or major arterial roads, this is the right spec.
Do You Need Acoustic Glass If You Live Under a Perth Flight Path?
Yes for sustained sleep-quality benefit. Acoustic performance depends on the complete window specification and installation. Ask for test data for the configuration being quoted. The Penot Double Glazing flight path noise reduction page covers the specifications. Existing research has documented the affected suburbs in detail; see our double glazing near Perth Airport and busy roads guide .
Will Double Glazing Help with Aircraft Noise Frequencies?
Yes, particularly with the acoustic laminated variant. Aircraft noise has significant low-frequency content (engine rumble, descent thrust), which is harder to attenuate than mid-range traffic noise. Acoustic laminated glass and thicker outer panes are designed for this frequency profile. The Rw + Ctr rating (an extension of Rw that weights low-frequency noise) is the metric to ask about for flight-path-exposed homes.
Product Questions
What Is the Difference Between Double and Triple Glazing?
Double glazing has two panes of glass separated by an aluminium or warm-edge spacer with an air or argon-filled gap (typically 12 to 16 mm). Triple glazing has three panes and two gas-filled gaps. Triple delivers Uw 1.0 to 1.4 (best spec) vs 1.8 to 2.5 for premium double. For Perth, SHGC matters more than U-value for most windows, so solar-control double is often the better cost-performance choice over triple.
What Frame Material Is Best for Perth Double Glazing?
Thermally broken aluminium dominates the Perth market for premium double glazing. The thermal break addresses the conduction problem of standard aluminium and delivers competitive thermal performance with the durability and finish range that aluminium frames offer. Timber and wood-alu hybrid frames suit heritage and architectural projects but require more maintenance than aluminium.
What Is Secondary Glazing?
A separate pane of glass added to the inside of an existing window, creating a sealed cavity between the original glass and the new pane. Lower cost than full window replacement, suitable for some heritage properties, and acoustic benefit is meaningful (though thermal benefit is more modest than full IGU replacement). Secondary glazing can be a stepped approach for budget-constrained projects or for heritage properties where the original window must stay.
Do You Have to Replace the Whole Window or Just the Glass?
Penot supplies complete replacement windows with new frames and glazing. We do not replace only the glass within existing frames. A site measure checks the opening, access and any work needed to fit the new window.
Process Questions
How Long Does Double Glazing Installation Take in a Perth Home?
Project run depends on project size, product spec and supplier capacity. The supplier confirms the timeline at the quote stage. Full walkthrough in our window replacement Perth process guide.
Do You Need Council Approval for Double Glazing in Perth?
Only for heritage-listed properties or properties in council heritage areas. For most Perth homes, double glazing is a routine window replacement not requiring development application. For State Register or Local Heritage List properties, a development application to the local council is required. Our heritage homes double glazing Perth guide covers the process.
What Warranty Should You Expect on Double Glazing in Perth?
Penot Double Glazing offers a 10-year frame warranty. For other warranty terms, including IGU seal, hardware and installation workmanship, ask at the quote stage. AGWA member suppliers typically follow industry-standard positions on IGU seal and install warranty, but confirm the specifics in writing before signing. Our how long does double glazing last Perth guide covers warranty terms in detail.
Does Penot Double Glazing Use Subcontractors for Installation?
No. Every installation is managed entirely by the Penot Double Glazing team. No subcontractors are used. This keeps the certification, the warranty position and the install quality consistent across projects.
Will Window Replacement Damage Internal Trims and Architrave?
The risk exists but is managed in the standard install process. Architrave is typically removed cleanly for access, then reset or replaced at the end. Where matching the existing trim is not possible (old timber profiles no longer in production), the supplier discusses options at the consultation stage. Painters can match existing wall paint where touch-up is required.
Do You Have to Move Out During Window Replacement?
No. The home stays occupied. Each room is opened and resealed within the same day in most cases, with the home secure overnight. Furniture near windows is moved or covered. Pets, kids and valuables need a plan but the household functions through the project.
Comparison Questions
Is Double Glazing Worth It for a Perth Rental Property?
For long-term holds, often yes. The energy bill reduction goes to the tenant. The landlord captures the resale benefit (rising NCC standards mean an upgraded property holds its market position better over time) and the comfort benefit (longer tenancies, lower turnover). For rentals being sold within 3 years, the case is weaker because the upgrade cost is not recovered through resale in that horizon.
What Is the Difference Between Toughened and Laminated Glass?
Toughened glass is heat-treated to be 4 to 5 times stronger than annealed glass; when broken, it fractures into small relatively harmless cubes. Laminated glass has two panes bonded with a PVB interlayer; when broken, fragments stay bonded to the interlayer. Both are Grade A safety glass under AS 1288:2021. Laminated is preferred for security applications and acoustic performance.
Is Double Glazing Worth It for an Apartment in Perth?
Yes when the apartment has west or unshaded north-facing windows, when noise from the street or surrounding apartments is significant, or when the building is targeting a higher energy rating. The complication is the strata approval process: in WA, windows are typically common property under the Strata Titles Act 1985, so the council of owners must approve the upgrade. Our double glazing for Perth apartments and strata guide covers the process.
Can You Double Glaze a Heritage Perth Home?
Yes, with two paths. For State Register or locally listed properties, the council development application process is part of the project. Premium architectural aluminium systems with 45 to 65 mm sightlines come closest to original timber sash proportions. Wood-alu hybrids preserve the timber sightline on the inside face while delivering modern thermal performance. Some State-registered properties require timber restoration with secondary glazing instead of full replacement.
What Is the Difference Between AGWA Members and Non-members?
AGWA (Australian Glass and Window Association) is the peak industry body for AU window and glass manufacturers, conducting compliance assessments of member companies. Members commit to AS 2047 and AS 1288 compliance, the AGWA Industry Code of Practice for Installation, and a Code of Conduct. Member warranty positions are standardised. Non-member suppliers may meet the same standards but do not carry the third-party audit and warranty framework.
Is Double Glazing the Right Answer for Every Perth Home?
No. Four cases where single glazing is the better financial decision: planned ownership under 3 years and the home is on the market, windows in good condition with favourable orientation, major renovation or demolition planned within 5 years, or budget constraint where secondary glazing on the worst rooms is the stepped alternative. Outside these cases, the upgrade typically pays back through a combination of energy, comfort, condensation prevention, acoustic and resale benefit over a 10-year horizon. Our hidden cost of single glazed windows Perth guide covers the cost-of-inaction framing in detail.
Where Penot Double Glazing Fits
Penot Double Glazing is a full AGWA member based at 92 Beechboro Rd S, Bayswater WA 6053. The standard double glazed windows and doors range covers thermally broken aluminium frames, solar-control low-e and acoustic laminated glass, and triple glazing for high-spec applications.
For a quote specific to your home, book a free in-home assessment. Compare options across the double glazing Perth range, call 1300 121 603, or visit the Bayswater showroom.
