Double Glazed Windows

Windows are an essential feature of any home because they allow us to view the outside and let natural light in. But they are often seen as the weak point in a property in terms of conserving heat and have traditionally been prone to leaks and very energy inefficient.

The common use of modern double glazed windows has put a stop to all that because window double glazing in its latest form is highly efficient as well as being extremely attractive. And the availability of custom double glazed windows from Ultimate Windows ensures each one fits perfectly, blends in beautifully with your home’s appearance and is extremely energy-efficient.

What are Double Glazed Windows?

A double glazed window comprises a frame, which may be made of aluminium, wood or increasingly from uPVC, and one or more sealed units that are generally referred to as insulated glass units (IGUs). Each IGU comprises two panes of glass (three in the case of triple glazing) that are separated by a spacer bar so that a gap is created between them.

Old-style spacer bars were often made from aluminium, but this acted as a thermal bridge that transferred cold outside air to the interior of a property. Modern spacers are more likely to be made from a combination of stainless steel and polypropylene that has a low thermal conduction rate and so reduces heat loss.

The panes of glass in an IGU have a gap of 6-16mm between them and this is filled with an inert gas, typically argon, that has a lower thermal transfer rate than air and so reduces heat loss. The complete unit is sealed to prevent the escape of gas and ensure the efficiency of the window.

Each sealed unit is potentially the weak point of a double glazed window and poor quality ones have a tendency to fail after a few years. It is imperative, therefore, that the manufacture of these units is of the highest standard using the best quality materials, as is the case for all our windows.

How Do Double Glazed Windows Work?

The gap that is between the two panes of glass slows down the thermal transfer between the two surfaces. Consequently, in winter, the outside pane will be cooler while the inside of the house is warm, and the aim is to keep it like that. The use of an inert gas such as argon helps to achieve the aim since it has a 34% lower transfer rate when compared to air.

The gap reduces the transfer of heat by conduction, however, since air cannot circulate in the narrow gap between the panes, convection is also reduced and that further minimises the transfer of heat. In addition to retaining heat, double glazed windows also help to reduce:

• External noise much more than old-style single glazed windows. Sound is a form of energy and causes vibrations of air and other molecules so that it moves in waves. When noise hits a glass window, the glass transmits the vibration to the other side at the sound wave frequency. However, the glass and the argon layer will absorb some of the energy, slowing the vibration frequency and diminishing the sound wave so the noise is not as great.
• Condensation that forms on the glass. Most air contains droplets of water, which are far apart in warm air but much closer as the air cools. At the dewpoint, the droplets combine into visible water, and this forms condensation on cold surfaces such as windows. Condensation can result from exhaled breath, and it forms in steamy rooms such as bathrooms and kitchens. Double glazing will reduce the formation of condensation because the internal surface of a window will tend to be warmer and so the dewpoint is less likely to be reached. Crystalline desiccant will be present within each sealed unit, and this will keep the gap dry. Internal condensation in a unit is a sure sign that the seal has failed.
• Solar gain from the sun, which can be achieved by fitting low-emissivity (low-e) glass. Normal glass will not stop solar gain so internal temperatures will rise in summer, but low-e glass has a coating that reflects the short-wave radiation of sunlight.

What Are The Benefits of Double Glazed Windows?

As already described, double glazed windows will reduce heat loss in winter, cut down condensation, lessen solar gain in summer and reduce noise pollution. All these will have the effect of creating a home that is much more comfortable.

Other benefits include:

• lower energy costs due to less reliance on heating in winter and air conditioning in summer
• reduced emissions leading to greater sustainability
• enhanced security since double glazed windows are much more difficult to break through, particularly when fitted with superior locking systems and safety glass
• virtually no maintenance when compared to old-style wooden windows since uPVC will not rot, crack or fade and does not need painting.

Why Should I Choose Double Glazed Windows from Ultimate Windows?

Poor quality glazed units will tend to fail quite quickly, releasing the inert gas and being far less efficient at reducing heat loss and blocking out external noise. Sub-standard frames will often fit badly, resulting in draughts and a further loss of heat. That’s why all our widows are made to a high standard from best quality materials and with quality control checks at every stage to ensure they meet our specifications.

All windows are made to measure so we know they will fit precisely, with no gaps or a need to make them fit. And they are all backed by our first-class customer service that starts with a survey that includes accurate measurements and an assessment of your needs. It extends right through the life of your windows, which will be a very long time, and even to their eventual replacement. So get in touch and we’ll start the process of supplying and installing your perfect windows.