Understanding Triple Glazing Thickness

If you’ve heard of triple glazing and you’re considering changing your windows or you need to install new windows, it’s worth understanding what triple glazing thickness is compared to double glazing. Triple glazing is particularly popular in extreme weather countries because of its thickness and growing in popularity in the UK. Yes, it is a little more expensive; however, homeowners with triple glazing say it is well worth the extra outlay for superior results. It promises improved energy efficiency and minimal heat loss as well as considerable noise reduction but does it deliver? Does a thicker glass really mean it is better? Let’s explore what triple glazing thickness is to help you decide whether it is right for you or if you can manage with double glazing. This article explains what triple glazing thickness is and compares it to double glazing so you make an informed decision as to what to choose for your home or business.


Glass Thickness – What Does It Mean?

Double glazing uses two sheets of glass and thickness is approximately 24mm (the optimum size) with frame depths approximately 70mm. Generally triple glazing is more expensive than double glazing and that’s because it is a thicker finished piece (using three sheets of glass, hence “triple”) with an overall thickness of 50mm plus.

Additionally, when installing triple glazed panels, because of the thickness, they must fit into window frames of 120mm depth. Most UK window frames are only 70mm in depth but there are deeper window frames available because more people are choosing triple glazing. It is much easier nowadays to get deeper window frames in the UK. Triple glazing 85mm depth, you should find many window companies able to provide this.

The weight of triple glazed panels is a little heavier than double glazed panels because of the thickness of glass. This means it’s important to use good quality fittings to take the weight and there are plenty available. It’s always worth buying quality to appreciate all the benefits of the end product.

It’s worth mentioning that the thicker glass panels are a very slightly different shade than clear glass and this is because they are made with an iron coating. The reason for the iron coating is to bring improved energy efficiency. However, the coating is barely visible to the naked eye.

Energy Rating Scheme

The energy efficiency in triple glazing is down to the construction and the thickness. Thicker glass will keep in more heat, as long as the frames that house the panels are built properly. As the UK is notorious for bad weather, triple glazing is an excellent choice for good insulation and warmth without cranking up the heating! In the UK there is a Windows Energy Rating Scheme which is the industry standard when looking at the overall performance of different glazing.
The maths involved calculates thermal performance, solar gain and loss of heat. The thicker panes of triple glazing improve efficiency.

U Values

The building trade measures energy efficiency for windows, walls, roofs and floors with a U value measurement. Let’s try and explain this. Regular windows have a single pane of glass and they are rated at 5+ on the U value scale. Remember, the higher the value, the less energy efficiency the glass has. Double glazing windows are thicker and rate at 1.6 U at worst, triple glazing which are even thicker, vary from 1 to 0.65 at best. The U represents the thermal energy in watts that is transported through a window, floor or roof component with the size of 1sq metre and temperature difference of 1 Kelvin [K] (=1°C). The mathematical sum is W/( m2K). If you look at a pane of glass, there should be a label on the panel to show the U rating. It’s complex to understand but the most important thing to remember here is the lower the rating, the better the energy efficiency, therefore you are guaranteed a better product with triple glazed panels.

The window energy rating takes into account U value and solar gain using a scale of A to G. A is the top rating. The energy rating doesn’t just take into account the glass; it represents the whole window which means the glass panel and the frame.


A Quick Comparison, Double Glazing Thickness V Triple Glazing Thickness

Double glazing is not as thick as triple glazing so doesn’t deliver the superior efficiency and noise reduction of triple glazing.

Thicker triple glazing windows will keep out unwanted noise and keep in the heat – reducing the need for as much central heating in the winter months, a must for the UK where it is cold and wet for much of the year!

Triple glazing is much heavier and thicker than double glazing for a quality product that lasts and lasts.

Being thicker and heavier, triple glazing is a little expensive but worth the extra outlay for the energy bill saving.

Triple glazing is growing in popularity in the UK.

Triple glazing is an attractive selling point when you come to sell your home.

Published on : 27th September 2016

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