Planitherm Total+

High performance Double Glazed glass units

Here at Aztec Windows all our windows and doors are supplied with high performance Low E glass units as standard, even in our porches and conservatories. Our Low E, or Low emissivity, glass units are manufactured using Planitherm Total+. Planitherm is a soft coat low E coating which offers exceptional energy efficiency when combined with our Halo System 10 and Rustique products.

Aztec Windows are members of the Planitherm installer Network

What is a soft coat Low E coating?

Soft coat Low E is a process where a chemical coating is applied to the glass pane to make standard float glass into energy efficient glass. The other way of achieving a low E glass pane is by using a hard coat glass such as Pilkington K.

What’s the difference between soft coat and hard coat low E glass units?

The main difference between soft coat and hard coat glass units is how the glass is made.

Soft coat glass is just regular glass with a chemical coating applied to one surface. This chemical coating performs much better than hard coat low e glass and offers a neutral tint but can be removed. The surface that is coated is always inside the cavity of the glass unit so this cannot happen though.

Hard coat glass is made differently. When making the glass itself the mix of Silica sand, ash and dolomite is changed. This change is raw materials gives the glass better thermal properties than normal float glass but not as good as the soft coat glass. Depending on the type of hard coat glass you may get a colour tint to the glass, Pilkington K for example has a slight yellow/orange tint.

So why Planitherm?

We use Planitherm glass because of its high performance. We believe in offering our customers the best products and Planitherm glass does the job better than the rest. Due to its unique coating not only does it reflect the heat back into your home but it helps generate free energy, in the form of heat, from the sun. As well as helping heat your home, it helps maximise the natural light entering you home with its neutral tint as well as helping to reduce draughts and cold spots around windows virtually eliminating internal condensation.

What about triple glazing? Is it worth it? Will I notice the difference?

These questions get asked a lot by customers.

As you are probably aware, the energy efficiency of windows and doors is measured with a U Value. Old single glazed windows generally had a U value of around 5.0, older double glazing (10 years +) around 3.0, while today's windows are required (by the building regulations) to have a minumum U value of 1.6. A rated windows have a U value of around 1.4 and triple glazing will get you to around 1.0 - 0.7.

If you are upgrading from single glazing or even old double glazing, to triple glazing the answer is yes, you will notice the difference. If however you are upgrading from modern double glazing, probably not so much.

Last updated on: 25th March 2018

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