Triple Glazing – Is It Worth All That Extra Money?

An Introduction to Triple Glazing

While the triple glazed windows concept is relatively new in the UK, it has been around for much longer in colder countries such as Scandinavia where homes typically have to endure extremely cold winter weather. While the UK doesn’t experience severe weather conditions like some countries in Europe, it still does experience harsh winters, which generally increase energy prices. Although things like insulating your floor, roof and walls do go a long way in helping keep your home warm, neglecting your windows could result in condensation and cold spots.

Benefits of U-Values and Triple Glazing

There are lots of benefits associated with installing triple glazed windows in your home. However, the important thing to keep in mind is that not all triple glazing is the same. Considering that there are many different types of systems in the market, the most important thing to consider when choosing triple glazing is the gap between glass panes (should be at least 16 mm) and the gas that’s used to fill the space (Argon is the best).

As an inert gas, Argon helps reduce the amount of heat lost through the panes. If the space between the panes is reduced, the sealed unit’s thermal performance will also reduce – unless you are using a more expensive gas such as krypton.

Generally speaking, the best size for a sealed triple glazed unit should be 4-millimetre glass and 16-millimetre gaps. This is what’s known as a 4/16/4/16/4 unit in the triple glaze industry, and the entire unit should be 44-millimetres in total. In comparison, the u-values between a 28-millimetre double glazed unit and a 44-millimetre triple glazed unit are quite substantial. The standard centre pane u-value of a double-glazed unit is 1.1, while that of a 44-millimetre unit is .62

Double Glazing versus Triple Glazing

Triple glazing is when an extra glass pane is installed over a double-glazed unit. The addition of this extra pane helps enhance performance in several ways:

  • The extra glass pane provides another layer of protection against cold temperatures, making a home warmer.
  • The addition of this extra pane of glass means adding an extra spacer bar at the edge of the pane to lower thermal transmittance.
  • The additional pane makes the window’s glass element more secure – the middle glass pane is generally toughened.
  • Triple glazed units have better sound insulation compared to double-glazed units with the same glass thickness.
  • Triple glazed units typically get A++ energy ratings.

Does Triple Glazing Have Any Downsides?

This is one question a lot of people ask when it comes to triple glazing. The biggest issue I have encountered with my triple glazed window would be external condensation. This is often because the outer part of the unit isn’t receiving any heat from the house. So, if the panes drop to a temperature that’s lower than the air outside air, the glass reaches ‘dew point’, and condensation happens.

This generally happens after a cold night and is best defined as a light misting that starts forming from the centre of your pane. If it were in the opposite place, this ‘misting’ would happen on the inside as the glass is being heated through the spacer bar and frame – the outer edge of the pane is warmer than its centre.


Triple glazing is amazing, and I would recommend it to anyone planning on changing their windows. While it costs more to install, the good thing is that it’ll ‘future proof’ your home. The good thing about triple glazing is that it lowers energy consumption, effectively lowering energy costs. So, while they are expensive, you should recover those extra costs within a short period through energy savings. Another thing about triple glazing is that it’ll make your home more attractive to potential investors if you are thinking of selling the property.

Are you thinking of having triple glazed windows installed in your home? Get in touch with KJM for more information on triple glazed windows in the UK and to receive a free window glazing quote. We also price for A-rated double glazing and additional upgrade costs to triple glazing.