Double glazing: is it worth it?

Double glazing is made of two panes of glass separated by a cavity filled with inert gas. It’s a very popular choice when renovating a property, even more so when the end goal is to put it on the market, as double glazed windows offer serious thermal and acoustic advantages with undeniably great insulation properties.
Double glazed windows seem pretty unavoidable these days but you’ll still have to make sure they’re the right option for your type of property as they come with their share of pros and cons.
Double glazing vs. secondary glazing
Double glazing belfast is different from secondary glazing which simply consists of adding an extra panel of acoustic and thermal insulation over a pre-existing type of window. This type of insulation is considerably less efficient than double glazed windows but it’s also much less costly and can be an option if you need to compromise on budget. It has one big advantage though as it can be removed if you need to clean the inside when mould, insects or dirt gets trapped. It’s also the only viable option for listed buildings in some cases when changing window frames isn’t possible.
Improving the “U-value” of a property
The energy sufficiency of any given window is evaluated thanks to a “u-value”: the lower the value, the better. The newer generation of double glazing can boast a U-value of around 1,6, against 5 for single glazing, so the improvement is indeed very significant. Insulation is improved by up to 40% on average.
Double-glazed windows might not be suitable for all types of pre-existing window frames: they’re often too heavy for wooden frames for instance and will require proper support and maybe a new set of frames depending on how old the building is. Be aware of this when budgeting for new windows.
Minor cons
One major issue to consider when installing double glazed windows is the condensation that can occur in between the panes and inevitably turn into mould. Don’t hesitate to ask for the help of a professional as this can mean that they have been badly fitted in the first place. If condensation tends to occur outside the glass, it’s all down to a lack of ventilation and can be easily prevented with the installation of vents.
Triple glazing
Triple glazing is made of three panes of glass and boasts extra insulation. It’s also much heavier and requires specific window frames that are able to carry the extra weight. Is it actually more efficient than double glazing? Cost is significantly higher but the u-value isn’t much lower than for double glazed windows. If you’re looking to renovate your home, triple glazed windows are a bit of an overkill but they might be the right option when planning out for a new buil

Christopher Walkey

Founder of Estate Agent Networking. Internationally invited speaker on how to build online target audiences using Social Media. Writes about UK property prices, housing, politics and affordable homes.

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