What to look for when buying double glazing

Double pane replacement windows have two panes of glass and a spacer in between that separates them. Double glazed windows are great at reducing heat loss, which keeps your energy bills low, especially when used in combination with a vinyl or fiberglass frame. This increases the overall energy efficiency of your windows. Perhaps the greatest benefit of double pane replacement windows is the cost factor, as they are generally cheaper than triple pane replacement windows.

Double Pane Frame Material

If energy efficiency is important to you, it is vital you look beyond double or triple glazing and also consider the frame material you use. When installing a double pane window, vinyl or fiberglass frames are generally the best choices as they are designed in a way that can support a double pane window without the window warping and bending. While double pane fiberglass windows might cost more upfront, over time you will be saving a significant amount on your energy bills thanks to its high-level of energy efficiency.

Double Pane Spacer

With double glazed replacement windows, one spacer is used to separate the two panes of glass. The space left between the two panes must be precise if you want to have the right amount of air flow between the glass panes. If you have too much space or simply not the right amount of space between double pane windows, it will not be as energy efficient as it could be.

Gas Fill

Often double pane fiberglass windows will have a gas fill between the panes of glass. This is to add extra thermal efficiency. Gases like argon and krypton are the most commonly used, however, argon is generally the most popular choice as it is much cheaper.

Glass Type

Double pane replacement windows perform exceedingly better than single panes of glass. This is because the glass used in double pane replacement windows acts as an insulator. By using a Low-E (low-emissivity) glass coating, infrared light is kept away while simultaneously allowing visible light to enter your home. Furthermore, heat mirror film can be used in double pane fiberglass windows for increased insulation.


Triple pane replacement windows are certainly a step up from double pane replacement windows. Due to the fact triple pane windows offer three panes of glass and two spacers, they are much heavier than double pane windows. However, the weight of a triple pane window will not affect the everyday use of your windows. The most common reason homeowners choose triple panes windows is because there is a significant difference in performance between double pane replacement windows and triple pane replacement windows.

Triple Pane Frame Material

Triple pane windows are noticeably heavier than double pane windows, which means they need a strong frame material if you want your replacement windows to last a long time. Vinyl and fiberglass are excellent options for triple pane replacement windows because they can withstand heavy loads without the risk of the window warping, twisting or bending over time.

Triple Pane Spacer 

Triple pane windows have two spacers that separate the panes of glass. Just like double pane windows, the spaces left between the three panes need to be precise in order for air to flow effectively between the panes.

Gas Fills

It is possible to use the same gas fills in double pane and triple pane windows. The main difference is triple pane fiberglass windows have gas filled into both air spaces between the panes of glass, which greatly increases the energy efficiency of triple pane replacement windows.

Glass Type

When it comes to triple pane window glass, two of three layers of a Low-E film can be added on the non-exposed surfaces of the glass (one per chamber). By having three layers of glass, your windows become an excellent noise-reducer, stopping outside noise transmitting inside, offering you a more comfortable and relaxed atmosphere inside your home.