Jason Windows

Types of Glass

These are the most common types of glass available for the home. Each glass type lists advantages, disadvantages and their main applications to help you choose the right glass for your home.

Annealed Glass

Annealed glass, also commonly known as float glass, is the basic flat glass product that is the first result of the glass manufacturing process. Annealed glass is cooled slowly under controlled conditions during production. This annealing procedure removes internal stresses from the glass.

Application

Annealed glass (also known as float glass) is the minimum standard for glass in the home. It’s also the base starting material for other glass types - such as Low-E, Laminated and Toughened Glass.

Benefits of Annealed Glass
  • Surface strength provides the wind-load performance and thermal-stress resistance needed in most architectural applications
  • Excellent visibility
  • Available in different tones and opaque options
  • Excellent light transmission in clear tone
  • Cost effective
Jason Windows Recommendation

Even though this is the standard glass type commonly offered in new homes, we recommend it be used when visibility and light transmission are important.

Things to Consider
  • Tends to break into irregular, sharp pieces when broken.
  • The strength limitations of annealed glass limit the size of usable pieces. Size limitations are set out by Australian Standards AS1288 - Glass in Buildings - Selection and Installation. Other types of glass that have a specific function are available as upgrade options. These glass types are often referred to as "performance glass" and can improve your energy and acoustic needs.
Toughened Glass

Toughened glass is often referred to as safety glass or tempered glass and is classified as Grade A safety glass under Australian Standards. Toughened glass is annealed glass, heated in a furnace then rapidly cooled. This toughening process reduces the risk of cracking. Toughened glass is five times stronger than standard annealed glass of the same thickness. The main purpose of toughened glass is to reduce the likelihood of injuries if broken by human impact.

Application

Generally, Australian Standards and Building Regulations stipulate Grade A Safety Glass must be used in:

  • All glass doors
  • Bathrooms (for all areas up to 2m height)
  • Door side panels (if less than 300mm away from the door and positioned 1200mm or less above floor level)
  • Areas that can be mistaken for openings (eg: full height fixed windows)
  • Low level glass if larger than 1.2 square metres. Areas under 1.2 square metres require a minimum of 5mm thick glass
Benefits of Toughened Glass
  • Suitable for when strength, thermal resistance, and safety are all important considerations
  • Safer – if broken, the glass shatters into tiny pieces rather than breaking into dangerous shards
  • Physically and thermally stronger than regular glass
  • Suitable for use in large openings
  • Available in different tones and opaque options
Jason Windows Recommendation

It is important to remember that Toughened glass cannot be reused or re-cut once installed, something to consider if you want to have a pet door later. Alternatively, you can have the pet door installed prior to the glass going through the toughening process.

Things to Consider
  • Sometimes exhibits minor distortion caused by the toughening process
  • Toughened glass cannot be cut after it has been toughened. For example, a sliding door installed with toughened glass cannot have a pet flap installed into the existing glass. The whole glass panel would need to be replaced and pre-cut with a pet flap opening.
Laminated Glass

Laminated Glass, also referred to as safety glass, consists of two sheets of glass permanently bonded together with an interlayer designed to improve acoustics and impact resistance. Laminated glass can be classified as Grade A safety glass only when it meets the relevant standards.

Application

Laminated glass is perfect for areas of the home most prone to injury from human impact such as bathrooms, doors and full-length windows. Laminated glass is suitable for sound reduction, energy efficiency, additional security and UV protection.

Benefits of Laminated Glass
  • Acoustic rated laminated glass can help to minimise some outside noises
  • Safer – if broken, glass fragments remain in the panel bonded to the interlayer, rather than breaking into dangerous shards
  • Standard laminated glass provides better protection against UV rays which can fade furnishings and kitchen benchtops.
  • Low-E laminated glass can reduce the amount of heat that is conducted through the glass by around 30% compared to annealed glass. Low-E glass further improves thermal efficiency by reducing glare.
  • Available in a range of tones and opaque options, such as:
    • Neutral - lightly toned
    • Grey
    • Green
    • Translucent - smooth milky finish
Jason Windows Recommendation

Check building regulations, some areas of your home may require the installation of laminated glass.

Things to Consider
  • Difficult to break in an emergency
Obscured Glass

Obscured (also known as "Patterned") glass which is often called privacy toughened glass, has a patterned texture or translucent finish intended to obscure or distort what is on the other side of the glass. Obscure glass can be produced as toughened or laminated safety glass.

Application

Obscure glass is commonly used in bathroom and toilet windows where both privacy and light are desired. Translucent glass, often referred to as frosted glass, is popular for modern aluminium front doors and can be paired with a toned glass to offer a different look to the standard translucent milky finish.

Benefits of Obscured Glass
  • Obscured patterned glass provides privacy without limiting light
  • Safer - if broken, the glass breaks into fragments rather than into dangerous shards
  • Textured obscured glass does not streak easily
Jason Windows Recommendation

It is important to remember that some council regulations stipulate the use of obscure glass overlooking a neighbours yard in two storey homes.

Things to Consider
  • Depending on the colour selected, pairing obscured toned and obscured translucent glass may reduce light levels
Toned glass

A variety of tones are available for all glass types. Glass is toned or tinted by including colouring additives to annealed clear glass during the manufacturing process. The majority of tones are created with shades of grey, bronze, blue or green. Toned glass significantly reduces glare and solar heat gain from the sun.

Supertoned glass, also known as supertinted, uses a heavier pigmentation to provide even greater solar heat control.

Toned glass should not be confused with tinted film applications for glass.

Application

With the sunlight absorbing properties in tinted glass, it is suited to warmer climates when ideal window orientation is not achievable. The coloured tone within the glass absorbs a greater proportion of solar heat in comparison to clear glass.  Toned glass is particularly useful for reducing the suns impact on unshaded windows.

Solar heat gain coefficient (SHGC) is the fraction of solar radiation admitted through the glass either transmitted directly or absorbed and subsequently released as heat inside your home. The lower the SHGC, the less solar heat is transmitted.

Benefits of Toned Glass
  • Reduction in heat and glare
  • Reduces furniture fading
  • Reduces cooling costs
  • Minimal exterior reflectance
  • Increases privacy during the daylight
Jason Windows Recommendation

Toned glass will reduce the amount of sunlight entering the home year-round. With its sunlight absorbing properties, the use of toned glass in north facing windows and doors is not recommended if you want to harness the winter sun to warm your home. In colder areas sunlight entering the home in winter is free heating that reduces costs, thus toned glass would not be suited.

Tones can be added to any kind of glass to improve performance further. For example, Low-E laminated glass can be paired with a grey tone to improve energy efficiency further and reduce glare.

Things to consider
  • Outlook visibility could be reduced depending on the tone selected
  • Visible light will decrease in thicker glass
  • Toned glass will not look the same at night, lit rooms will be visible from the outside
  • Dark tones in smaller rooms can seem claustrophobic
  • Light transmittance is reduced
Low-E Glass

Low-E performance glass has a coating that allows natural light through without emitting radiant heat, maximising light and energy efficiency.

Application

Where greater solar and thermal control is required in the absence of natural heating, Low-E Glass can be used. Also an option to consider towards the Energy Efficiency Rating for new homes, especially in cases where plenty of light is desired.

Benefits of Low-E Glass
  • Provides improved insulation and greater solar control when using tints so you can enjoy a comfortable temperature within your home all year round
  • Reduces the rate at which furniture fades by absorbing UV radiation
  • Comes in a range of different tones
Jason Windows Recommendation

The cost of investing in Low-E glass can be offset against your future energy bills, and is a cost effective alternative to double glazing.

Things to Consider
  • Special care needs to be taken when cleaning Low-E glass
  • Has a slight hazy look from some angles
Double Glazing

Double glazing consists of two panels of glass which are separated by a layer of air or argon gas and then sealed. Argon gas is known to create a more effective insulation barrier than air by greatly reducing both heat flow and thermal conductivity through the glass. Jason Windows only uses Argon gas in all double glazing products.

Application

The thermal benefits of double glazing makes it ideal for windows in rooms where there is the desire for more control of heat gain and loss through the glass.

Benefits of Double Glazing
  • Excellent insulation performance reducing energy costs. Performance glass types such as Low-E can be used in double glazing to further increase energy efficiency
  • Can minimise noise if the right glass combinations are selected. This is beneficial if you live on a busy street or under a flight path. If noise reduction is your only requirement laminated glass will be a more cost effective solution
  • Reduces condensation with can occur when warm humid air condenses on the relatively cold glass surface
  • Reduces the need for insulation provided by windows coverings. Where privacy is not a concern, curtains of blinds may be deemed unnecessary for room temperature comfort levels.
Jason Windows Recommendation

 Double glazing is best applied to the rooms most affected by thermal impact. It is important to consider the reasons for double glazing and all available alternatives. For example, Low-E glass for example is often a cost-effective alternative for when thermal comfort is your only priority.

Things to consider
  • Low-E glass is more cost effective than double glazing
  • Risk of thermal stress should be considered for Low-E glass applications