New Home Windows

Windows are a very important aspect of a home and careful consideration should be taken before accepting whatever a builder provides as standard. Typically builders wont tell you about the options that are available and simply provide the minimum required to comply with local regulations. They contribute to aesthetics, airflow, soundproofing, heating, cooling and privacy.


Your first decision is to decide on the material such as timber, aluminium or uPVC.


Cedar Timber

Timber frames are normally made from cedar which requires a lot of maintenance with sanding, re-staining, re-coating, and suffer from blackening/greying of timber. Timber can also be very expensive. If you have dogs, its very difficult to fix scratches on the doors. They can be stained in different colours and they also offer a wide profile.

Aluminium & Thermally Broken Aluminium

Thermally Broken Aluminium

Aluminium is common and has little maintenance compared to timber however comes with drawbacks. If they aren’t thermally broken, more of that later, they perform poorly from a thermal perspective and will contribute significantly to the cooling and heating of a home.

Thermally broken aluminium is thermally efficient. A non-conductive piece like uPVC is placed in the middle of the frame to prevent heat and cold from transferring through. Visually it looks the same as standard aluminium.



uPVC offers many of the benefits of timber frames and aluminium but with fewer drawbacks than both. They are the most thermally efficient material and offer wide profiles like commercial windows.

Composite Windows (Timber + Aluminium)

Composite Timber + Aluminium

You can also get composite windows where the inside is timber and the outside is aluminium which significantly reduces its maintenance.

AluminiumThermally Broken AluminiumTimberuPVC
Thermal Efficiency⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐

Aesthetics (Commercial Windows) + Sizing

With smaller custom luxury builders, they will generally use commercial windows which are just thicker frames and the glass is the same as residential. With commercial and semi-commercial windows they can also provide higher (>2.4m) and wider doors and windows and allow for double glazing. All other builders will provide residential windows which are small frames and they generally can’t accommodate double glazing.

Residential windows also come in standard sizes. If you want ones that are outside of these they become custom so even a few mm less can cost you more. The difference isn’t much though per window however, they can add up.

When increasing your ceiling heights consider increasing your door and window heights as they can look out of place otherwise eg. consider 2.34/2.4m window heights with 2.7m ceilings. Also consider the head heights for the windows and make sure they are aligned with each other. For ceilings above 3m consider having standard window heights and having a highlight window above them.

75 Beautiful Highlight Window Home Design Ideas & Designs | Houzz AU
Highlight Windows

Doors and windows above 2.34m might not be possible with standard residential frames so you may be forced to upgrade to commercial frames. There is also a hard limit on the height of the commercial doors so go onto the manufacturer’s website to confirm these heights.

Wideline Sliding Door: Max Heights and Widths
WidelineSemi-commercialAscend 25/40
StegbarCommercialCapral 900 (TBC)
Window Brand Ranges

Types of Windows

Consider the use of the windows because some types of windows provide a sealed system like an awning window where heat and sound cant pass easily whereas a sliding window will have a small gap in the middle of the window as it cant form a tight seal. Also when it’s raining some types of windows will allow rain to come in more easily than others eg. awning vs sliding.

TypeAirflowSound Isolation & Thermal loss (gaps)Open during RainPricingNotes
AwningBelow averageGreatY$$$
SlidingGreatBelow avgN$$These normally cost less than awning windows but thats not always the case.
CasementGoodGreatY$$$$You might not be able to use flyscreens on these unless you go with full commercial windows.
Double hungGreatBelow avgN$$$$$
LouvreGreatTerribleN??These arent good for thermal or sound protection
Tilt & TurnGreatGreatY$$This is a hybrid of a casement and an awning window so you get the benefits of both. It opens inwards. Its more common for uPVC frames.
Types of windows


Skylights will cost around $2300 to $2700 for a fixed skylight. Theres a few different standard sizes from Velux that are worth looking into as the cost different isnt much between them.

Pitched Roof Openable Skylights - 2021
Skylight sizes (pitched roofs)

Glazing Options

Double Glazing

Double glazing is where a window is constructed with 2 panes of windows that are separated by a pocket of air and that pocket of air will usually be injected with a type of gas. The thickness and type of window panels can be adjusted too.

Double glazing will help ensure there’s less thermal loss through your windows as well as provide some soundproofing to that room where its required. This will also help with BASIX/NatHERS assessments. Double glazing can be 20-40% more but when you consider the difference between $500 and $700 for a window, its not too much. This pricing also assumes the single glazing is on the commercial type of window, otherwise, the cost difference will be more.

For larger windows/doors consider the total weight of it as it might require onsite glazing (unsure how this work for double glazing) or cranes to be used as it can be too heavy for people to carry themselves.

Glazing for sound/acoustics/noise reduction

Double glazing has mixed messaging from the suppliers on its effectiveness. To be effective for sound proofing you would require a gap of over 100mm to be as effective. Wideline for instance use a product called Viridian’s VLam Hush™ which is a laminated glass product suitable for acoustic treatments. Density plays a crucial part.

Glazing for thermal efficiency

Low-e or Comfort (Viridian) are often used as alternatives to double glazing as you don’t need to upgrade the frame to commercial ranges and can save you on onsite glazing costs too.

Other window costs

Onsite glazing – If a single window is more than 80kg (there can be leniency in this) it may require onsite glazing which would cost at least $500 per window. The window may also require craning which would add another significant cost.

Thermal Efficiency & How to Compare Windows for this


Window Factors

WERS give you the ability to search for the performance of the windows and frames. To keep things like for like they use the same size window to compare. The important codes to know about are

  • U-values – measure how well the window will retain heat in the winter and reject heat during summer. The lower the U value, the greater a window’s resistance to heat flow, and therefore the better its insulating value. This is a similar concept to the R rating for insulation however a higher rating is the target in this instance. A well performing UVal is around 2 which mostly uPVC, thermally broken aluminium and timber frames can achieve.
  • SHGC (Solar Heat Gain Coefficient) – measures how well a window product blocks heat caused by sunlight. A product’s SHGC value is expressed as a decimal number between 0 and 1; the lower a window’s SHGC value, the less solar heat it transmits.

For sound and air infiltration you ideally want a window that can have a full seal when closed like an awning, casement or tilt and turn window. Sliding windows arent able to do this as well but they have improved over the years. To measure this you should compare

  • AI values (Air Infiltration) – The lower the better and under 0.3 is good but this needs further investigation on the ideal values. A fixed window is 0. Wideline has an Ascend awning window of 0.22 and a Paragon sliding window which is 0.23, so not much difference between them.

Window Material Impact on Thermal Efficiency

For thermal efficiency thermally broken windows are a major factor to consider as these enable things like double glazing and low-e treatments to be much more effective. uPVC, timber and thermally broken aluminium are options here which will generally cost more than standard aluminium windows but its not always the case.

On a standard aluminium window its rare to find a UVal lower than 3 with double glazing and low-e whereas with thermally broken frames 1.5 is easily possible. A lot of people spend money changing from a single glazed window which has a rating of 6 to double glazing which just gets to 3.6 which is good but not great.

Wideline Windows

From Wideline these are the specs for comparison to see the impact of the various glazing and frame options (Paragon is the top range and Ascend a mid range):

Window TypeFrameGlazingUValSHGCTvAI
AwningASCEND Awning Window ‐ Double Glazed4mm Clear / 6mm Argon Gap / 4mm Clear3.80.520.530.22
AwningASCEND Awning Window ‐ Double Glazed4mm Clear / 12mm Argon Gap / 4mm Clear3.60.520.530.22
AwningASCEND Awning Window ‐ Single Glazed6.38mm Clear Laminate5.80.540.570.22
AwningParagon Awning Window ‐ Single Glazed6.38mm ComfortPlus Neutral60.330.310.3
Bi-Fold DoorParagon Bi‐Fold Door ‐ Double Glazed4mm Clear / 6mm Air Gap / 4mm Clear4.40.520.540.38
Bi-Fold DoorParagon Bi‐Fold Door ‐ Single Glazed6.38mm ComfortPlus Neutral4.50.370.40.38
Double HungParagon Double Hung Window ‐ Double Glazed4mm Clear / 6mm Argon Gap / 4mm Clear4.60.520.531.02
Double HungParagon Double Hung Window ‐ Single Glazed6.38mm ComfortPlus Neutral50.370.391.02
Fixed WindowParagon Fixed Window ‐ Double Glazed4mm Clear / 6mm Air Gap / 4mm Clear4.10.630.660
Fixed WindowParagon Fixed Window ‐ Single Glazed6.38mm ComfortPlus Neutral4.30.460.510
Fixed WindowParagon Fixed Window ‐ Single Glazed6.38mm Clear Laminate60.720.780
LouvreAscend Louvre Window ‐ Single Glazed6.38mm Translucent Laminate6.2*0.48*
Sliding DoorASCEND Sliding Door ‐ Double Glazed4mm Clear / 6mm Argon Gap / 4mm Clear40.60.630.32
Sliding DoorASCEND Sliding Door ‐ Double Glazed4mm Clear / 12mm Argon Gap / 4mm Clear3.80.60.630.32
Sliding DoorParagon 2 Lite Sliding Door ‐ Single Glazed6.38mm ComfortPlus Neutral4.70.380.430.23
Sliding DoorASCEND Sliding Door ‐ Single Glazed6.38mm Clear Laminate6.10.630.690.32
Sliding WindowASCEND Sliding Window ‐ Double Glazed4mm Clear / 6mm Argon Gap / 4mm Clear4.50.560.580.3
Sliding WindowParagon Sliding Window ‐ Single Glazed6.38mm ComfortPlus Neutral5.20.360.380.23
Sliding WindowASCEND Sliding Window ‐ Single Glazed6.38mm Clear Laminate6.50.590.630.3
Stacker DoorASCEND Sliding Stacker Door ‐ Double Glazed4mm Clear / 6mm Argon Gap / 4mm Clear40.60.630.91
Stacker DoorParagon 3 Lite Sliding Stacker Door ‐ Single Glazed6.38mm ComfortPlus Neutral4.70.390.430.39
Stacker DoorASCEND Sliding Stacker Door ‐ Single Glazed6.38mm Clear Laminate6.10.630.690.91
Wideline window and door WERS ratings

Stegbar Windows

Window TypeFrameGlazingUvalSHGCTvAI
AwningAluminium Awning Window – Double Glazed4mm Clear / 6mm air Gap / 4mm Clear4.40.570.590.04
AwningAlumiere Awning Window – Double Glazed4mm Clear / 12mm Argon Air Gap / 4mm Clear4.10.560.571.14
AwningAluminium Awning Window – Single Glazed6.38mm ComfortPlus Clear4.90.520.60.04
AwningAlumiere Awning Window – Single Glazed6.38mm ComfortPlus Clear5.30.520.581.14
AwningAluminium Awning Window – Single Glazed6.38mm Clear Laminate6.20.610.650.04
CasementAluminium Casement Window – Double Glazed4mm Clear / 6mm Air Gap / 4mm Clear4.20.570.585
CasementAlumiere Casement Window – Single Glazed6.38mm ComfortPlus Clear50.510.580.27
Fixed WindowAlumiere Fixed Window – Double Glazed4mm Clear / 12mm Argon Air Gap / 4mm Clear3.30.670.710.12
Fixed WindowAlumiere Fixed Window – Single Glazed6.38mm ComfortPlus Clear4.10.620.730.12
Sliding DoorAlumiere Sliding Door -Double Glazed4mm Clear / 12mm Argon Air Gap / 4mm Clear3.80.580.61.51
Sliding DoorAlumiere Sliding Door – Single Glazed6.38mm ComfortPlus Clear4.40.520.611.39
Sliding WindowAluminium Sliding Window – Double Glazed4mm Clear / 6mm Air Gap / 4mm Clear4.60.570.62.97
Sliding WindowAlumiere Sliding Window – Single Glazed6.38mm ComfortPlus Clear4.80.560.650.63
Sliding WindowAluminium Sliding Window – Single Glazed6.38mm Clear Laminate6.20.690.751.28
Stegbar window and door WERS ratings

Deceuninck uPVC Windows

Window TypeFrameGlazingUValSHGCTVAI
AwningDeceuninck uPVC Awning Window – Double Glazed4mm Clear / 16mm argon / 4mm Clear2.3540.450.460.34
AwningDeceuninck uPVC Awning Window – Double Glazed4mm Clear / 16mm argon / 4mm LowE Plus1.750.350.450.34
Tilt & TurnDeceuninck uPVC Tilt and Turn Window – Double Glazed4mm Clear / 16mm argon / 4mm Clear2.3230.450.460.27
Tilt & TurnDeceuninck uPVC Tilt and Turn Window – Double Glazed4mm Clear / 16mm argon / 4mm LowE Plus1.7390.350.450.27
Sliding WinDeceuninck uPVC Sliding Window – Double Glazed4mm Clear / 16mm argon / 4mm Clear2.6290.510.530.8
Sliding WinDeceuninck uPVC Sliding Window – Double Glazed4mm Clear / 16mm argon / 4mm LowE Plus1.9440.40.530.8
Deceuninck window and door WERS ratings


Its very difficult for a single glazed window, no matter the treatment applied or the thickness to come close to a double glazed window in terms of thermal efficiency. There are many factors that go into a double glazed window:

  • Thickness of the 2 glass planes
  • Type of windows used
  • Gap between the window panes
  • Argon or other insulating gas used

Viridian is one of the main glass suppliers in Australia and has multiple products that can be considered for your use case.

Low-e windows are common and they make a significant difference compared to standard clear windows. They go through a process of either (source from Viridian – what-is-the-difference-between-hard-coated-and-soft-coated-low-e-glass)

  • Soft coated Low E glasses
    • must be incorporated into a double glazed unit as the coating is ‘less durable’ than a hard coated (pyrolytic) coating when exposed to the atmosphere. Soft coated Low E glasses cannot be glazed in single glazed applications but hard coated products such as ComfortPlus™ and EnergyTech™ can.
    • Pyrolytic coatings have a long shelf life, whereas soft coated Low E glasses do have a shelf life and will begin to break down if stored for too long without being incorporated into double glazed units.
    • Soft coat Low E glasses such as Viridian LightBridge™ or PerformaTech™ have significantly lower U values than hard coated pyrolytic glass types.
  • Hard-coated Low E glasses are manufactured online during the float manufacturing process where soft coats are applied by a special offline process at some time after the glass has been manufactured.

Single pane Low-e glass has the coating on the inside and can be difficult to maintain a clear window:

Types of Low-e glass

Glass Options

Oceania Glass provide the larger window manufacturers glass and this would often go through Veridian. The table below compares the different glass types and their technical specifications. These don’t take into account the frame’s performance so these are easier to compare against each other.

UV – The amount of UV light the glass blocks out
% Light – is the amount that passes through the glass

ApplicationsProductThickness% LightUVUValSHGCNotes
Plain glassVFloat – Clear6mm88605.80.82
Plain glass + No UVVLam – Clear6.38mm87<15.70.79
AcousticsVLam Hush – Clear6.5mm87<15.70.78
Better SHGC + PrivacyEvantage – Clear6mm68303.80.63
Low-eSmartGlass – Clear6mm81483.60.70Same as EnergyTech, toughened, and standard sizing. Branded under smart glass. Sold to 2-3 major window suppliers
Low-eEnergyTech – Clear6mm81483.60.70Architectural – not standard size
Low-eEnergyTech – Clear12mm79423.60.63Monolithic (not laminated). Toughened different to lamination
Low-e + No UVComfortPlus – Clear6.38mm82<13.60.69Laminated glass – UV + Safety
Low-e + No UVComfortPlus – Clear12.3879<13.50.62
Low-e + Acoustics + No UVComfortHush – Clear6.5mm81<13.60.67
Low-e + PrivacySolTech – Neutral6mm63413.70.54
JailGuard – Neutral23mm56<13.00.47
Glass Options from Oceania Glass / Veridian

Thermally Broken Window Frames

Thermally broken window

Double glazing is important and it will reduce the chance of condensation forming and provide thermal insulation however if the frames aren’t thermally broken then it will mean a transfer of heat or cold through the frame and it can cause condensation on the frame and have a lower overall performance of the window. Think of a thermally broken window as having an insulating material in the middle of the frame stopping the transfer of heat/cold.

This is more of an issue in aluminium windows. Timber and uPVC window frames aren’t impacted significantly by this.

Thermally broken frames are more likely to have benefits in climates with temperatures under 5oC but this needs further investigation in your circumstance.

The cost of thermally broken frames can be significant. There are cases where its 40% more and many manufacturers dont have them as an option.


These can cost around $50 per window. For BAL rated homes they need to be made of one that is BAL rated eg. aluminium. Casement windows may not be able to have ones installed unless you upgrade to fully commercial ones.

For doors, you want to ensure that even if you don’t include them to start with that they are provisioned for ones to be installed in the future.

Theres many types of flyscreens including fixed and retractable ones. Some indicative costs are:

  • Standard window flyscreen – $45
  • Retractable flyscreen – $2000 for 4m bifold doors
Standard window flyscreen
SecureLine Strongest Security Screens - Wideline
Rigid Door Flyscreen
IDeal retractable flyscreen door screens for french and bifold doors.
Retractable Flyscreen
Secure Flyscreen Door

Snapshot of pricing as of Jan 22

TypeRangeDimensionsNormalDouble GlazingLaminatedHushComfort HushNotes
CasementAscend1555 x 855660
CasementParagon1900 x 8111550
Awning (1 window)Horizon1900 x 1000750
Awning (1 window)Ascend1900 x 1000900
Awning (1 window)Horizon1555 x 855450
Awning (1 window)Ascend1555 x 855650
Awning (1 window)Ascend450 x 1100400500
SlidingAscend490 x 1100640100mm of glass so not worth doing
StackerHorizon2100 x 36002950
StackerAscend2100 x 36003460
StackerAscend2400 x 36003750
StackerAscend2700 x 36004500 (3100)4500 was price previously quoted
StackerParagon2700 x 36003300Same door handle on Ascend but doesnt suit it. Haliday and Bailey
StackerParagon3000 x 36003600
Sliding WindowsHorizon (standard)1210 x 860210N/ACant double glaze horizon sliding
Sliding WindowsHorizon (custom)1210 x 870230N/ACant double glaze horizon sliding
Sliding WindowsHorizon (custom)1220 x 860210N/ACant double glaze horizon sliding
Sliding WindowsAscend 251210 x 860500700
Sliding DoorsAscend 252700 x 15002000
Sliding DoorsParagon2700 x 15002200
FixedAscend2400 x 1000930
FixedAscend2400 x 115060010003050 Ascend max height
FixedAscend 252700 x 11506501100
FixedAscend 253000 x 200018002200 (just window) + site glazing8mm toughened
FixedParagon2400 x 10006001050
FixedParagon2400 x 11001100
FixedParagon2700 x 20003500
Pricing below from RoseberryNormalDouble GlazingLaminatedHush GlassComfort Hush Glass
Awning (1 window)Ascend1600 x 9001130
Awning (1 window)Paragon1600 x 9002000
Awning (individual glazed colonial bar)Paragon1600 x 9002020
Sliding (2 lites)Ascend1600 x 9001010118010804mm float glass, veridian. Double glaze, 6mm glass, 8mm gap, 6mm
StackerAscend 252700 x 3430failing465056005750
StackerParagon2700 x 343067005700
SlidingHorizon2400 x 18001779N/A
SlidingHorizon2400 x 18101660N/A
SlidingAscend2400 x 181020802630
Awning (AFFA)Horizon450 x 4420N/AN/AN/A
Awning (AF)Horizon2210 x 450730960
Awning (AFFA)Ascend 25450 x 442020901764
Wideline pricing

2 thoughts on “New Home Windows”

  1. Is there any way to simplify window information: windows glass and frames, eaves and orientation have become so complex it is impossible to tease out anything sensible!

    1. If this is to get a better way to measure the performance then the U-Val and SHGC values provide this information. It accounts for all those variables.

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