Different Types of Window Glass

Image of sash window

Not all windows are the same. You may have noticed that windows come in a number of types and patterns when looking to install them in your home. You can choose from a variety of frames, including aluminium, uPVC, and wood, as well as several types of glass for your windows.

According to David Chahine from Primal Glass Replacement, different types of window glass fall into three main categories: float glass, patterned glasses, and toughened or treated glasses. Different types of glass come with different advantages and disadvantages, so it’s worth looking into each type to decide which will work best for you.

Float Glass

Float Glass

Float glass is made by pouring molten glass into a tank of water. As the glass cools, it reduces in thickness and flattens against the bottom of the tank. Float glass is often used for windows because it offers clear visibility and often has an extremely thin profile for efficiency. It comes in three grades: normal, which has a green tint; low-iron, which is the clearest type of glass available; and extra-clear, which has a blue tint.

Pros & Cons – Float glass is cheap and easy to produce, as well as resistant to stains and weathering. However, it can break or shatter easily because of its thinness.

Tempered Glass

Tempered Glass – Tempered or toughened glass is four times stronger than regular float glass and is often used as safety glass in places like doors and stairwells. It’s made by heating the glass and then quickly cooling it in a controlled environment. The cooled glass is then heated and rapidly cooled again, causing the outer surface to cool faster than the inside, which causes the center of the glass to compress and grow stronger due to internal pressure.

Pros & Cons – Tempered glass can reduce noise from outside and is often used in aquariums and windows in high-traffic areas. However, it’s more expensive than other types of glass and can break when hit with a heavy object because of the rapid change in temperature during manufacturing.

Laminated Glass

Laminated Glass

Laminated glass is composed of two or more sheets of glass that are bonded together by a clear, plastic layer. The plastic core typically consists of vinyl but can also be made from polyester, acrylic, or other synthetic materials. Laminated glass is often used in car windshields because it reduces noise and offers protection against damage from small collisions.

It’s also used in doors, safety glazing, and partitions.

Pros & Cons – Laminated glass is much stronger than regular window glass and very difficult to break. However, it’s also difficult to drill or cut, so laminated glass is mainly used for its shatterproof and insulation benefits.

Low E Glass

Low-E Glass – Low-E stands for “low emissivity,” and this type of glass is specially designed to retain heat in the winter and keep it cool in the summer. It’s often used as window film and can also be added to existing windows by replacing old panes with new Low-E glass or applying a sheet of Low-E film over old glass.

Pros & Cons – The biggest benefit of Low-E glass is its energy efficiency, which can save homeowners money on their heating and cooling bills throughout the year. However, it can’t be used everywhere because it causes solar gain in some conditions. It’s also more expensive than regular float glass and toughened glass.

Double Glazing


Double glazing is a term used to describe two pieces of glass that are together inside the window frame. In other words, it’s two layers of glass with a gap in the middle. Double glazing works because trapped air is a poor conductor of heat, which helps prevent heat from escaping during the winter and entering during the summer.

Pros & Cons – Double glazing does a better job of keeping cold air out in the winter and hot air out in the summer than single glazing, so it reduces drafts and increases your home’s energy efficiency. However, this type of glass is much more difficult to install and can be quite expensive if you have to pay a professional.

Member of Design Institute of Australia, multi-disciplinary designer, qualified interior decorator with extensive knowledge in diverse softwares including, Adobe Photoshop, AutoCad, InDesign, SketchUp and all Microsoft Office divisions.