Understanding Double Glazing – What is It?

Windows classified as double glazed consist of two layers of glass with a gap between them that acts as a barrier and insulation. This gap is usually filled with argon or another inert gas. Alternatively, it may be left as a vacuum. Both perform the same function – to reduce heat movement from the window’s external side to the internal side and vice versa.

Understanding Secondary Glazing – What is It?

Windows classified as being secondary glazing involves the installation of additional layer of glazing to the internal side of a window already in place, that’s normally single-glazed. While they are sometimes permanent, these solutions are often temporary.

Double Glazed Windows are More Expensive

It makes sense that double glazed windows would be more expensive than secondary glazing, as the installation of double glazing involves the installation of a completely new unit and is not just a simple retrofit.

As noted above, for the gap and the whole point of double glazing to work effectively, it needs to be sealed tightly to trap air on the inside and outside and is filled with a vacuum or inert gas. That’s why when you hire a company to install windows, they will need to visit your home to measure each window so they can design and create a window specifically for your home.

Secondary glazing, therefore, is considerably cheaper. There are even DIY kits out there or installers who will simply come out without much consultation and install a secondary glazing unit on the interior of an existing window.

Which is Best for Combatting the Loss of Heat

A common reason why homeowners choose to have their windows replaced with either secondary or double-glazed windows is to improve how efficient the property is at retaining and maintaining energy, specifically heat energy. This in turn, as you probably know, helps when it comes to reducing their utility and heating bills. Both are good at performing this function.

However, there is no competition as to which is better because double glazing is many times more effective at preventing the loss of heat from your home. Even though they are the most expensive option upfront, as they last at least 20 years and often more, you will eventually see a return on your investment.

Heating bills are sure to decrease once double glazing has been installed, as if your house is on a thermostat, it takes relatively less heat to keep your home warm. Not only that, but double glazing is able to keep your home cool throughout the summer months yet remain toasty in the winter.

Which is Best for Acoustic Insulation?

Again, when it comes to reducing noise pollution, both secondary and double glazing are great at performing this role. However, it’s secondary glazing windows that edge out ahead of double glazing. As there are two different sections in secondary glazing, something you don’t get in double-glazing units, there are two completely independent barriers that prevent noise traveling through them.

The bigger the gap between these two glass windowpanes, the more effective the effect of dampening the sound is. Therefore, as double-glazing doesn’t have as nearly as big a gap between them, it’s not as effective at cutting down the noise.

Which is the Right for You? Double Glazing or Secondary Glazing?

So, rather than them being the same or exactly as good as one another, there are distinct differences to double glazing and secondary glazing. Yes, they perform the same role in your property. However, it really depends on which option is best suited to your requirements, needs and budget.

As double glazing constitutes a huge investment, it may not be the wisest choice if you are looking to simply reduce the sound of a busy main road outside your property. Whereas, if you are looking to improve the energy efficiency of your property, and you live in a listed building or property in an area listed for conservation, you need to consider that planning permission is required.

The best option for one person, may be the worst option for another. Discuss your options with Evolution and we will be happy to help guide you to the best decision about whether you are going to have secondary glazing installed or require a full installation of double-glazing units.