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Pros & Cons of Double Glazing Vs Triple Glazing Windows


Which is more suitable for your home, Double Glazing or Triple Glazed Windows?

You’re looking to upgrade your windows or get new windows installed and wondering if it’s worthwhile getting triple glazing to ensure you insulate your home as much as possible. However, what are the other advantages of going triple glazing and will you really benefit from them?

In this blog article, we take a quick look at the Pros & Cons of Double Glazing Vs Triple Glazed Windows?

Back to Basics

Double Glazing Windows

Double glazing is when there is a space between the outer and the inner surfaces of the window. The gap between the two panes of glass, sometimes filled with a gas, reduces convection of cold and heat whilst also acting as a sound buffer. The size of this gap is quite important. Too small and it becomes less effective, too large and the air in the gap will circulate and will also reduce the effectiveness. High-quality glass can also make a difference, insulating your home more efficiently.

Triple Glazing Windows

What you get with triple glazed windows is the same as the above, but with a third pane of glass. The third pane distinctly improves sound insulation and thermal insulation, because now you have two air gaps. If you combine this with high-quality glass and warm edge spacers, you have a very energy efficient window.

Having been in the glazier business for a number of years, here are some of the rough findings we have discovered, if a room was heated to 21 degrees, and it was suitably cold outside, the inside of a single glazed window would give an average reading of 1 degree. A double glazed window would be roughly 16 degrees, and triple glazing window would give a reading of 18 degrees.

There is easily a big difference from single to double glazing, but not such a big gain with double glazing and triple Glazed Windows.

Double Glazing Vs Triple Glazing? – The Pros & Cons

Advantages of Triple Glazing

  • As the statistics demonstrate above, triple glazing is slightly better than double glazing for heat efficiency.
  • The third pane offers enhanced noise reduction.
  • Triple glazing is better at eliminating hot & cold spots in the home.
  • Triple glazing also has a better condensation control, which helps keep your home healthier.
  • Triple panes of glass make the window more secure.

Advantages of Double Glazing

  • The biggest advantage of double glazing is that it’s cheaper than triple glazing.
  • The frames are thinner and less bulky.
  • Double glazed window units weigh less and therefore doesn’t put so much strain on the hinges & corner joints.
  • Triple glazed windows with the middle pane made from float glass can have a problem with the middle pane cracking due to temperature differences from the outside & inside – you should use toughened glass which again comes at an extra cost. 
  • Double glazing will be cheaper to repair in comparison to triple glazing, given there will be less of the window to repair.

So which is more suitable for your home, Double Glazing or Triple Glazing?

If you are after the most energy efficient window that you can get, and you have the budget then triple glazing would be the right option.
However, if you are budget conscious but still want good performance, a good quality A++ rated double glazed window will be more than up to the task, which will still guarantee to you a warmer, healthier home with a significant noise reduction.

Throughout most of New Zealand, the added performance of a triple glazed window is not always really that necessary to have. We don’t really suffer from extremes of cold, like rural Canada or Scandinavia countries.

One last thing to also consider is that the extra cost of triple glazing is not necessarily going to be recouped by savings on your household bills when compared to what you get from a good quality double glazed window.

If you’re still unsure about what you want for your home, then get in touch with Thermoglaz for a free consultation.

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