Is Double Glazing compulsory?

Over the years, single glazed windows have become more and more unusual. But what exactly is it that’s caused this change? Is it down to a popular personal preference, or are there government guidelines enforcing it? 


While there are no simple yes or no answers, it’s definitely worth knowing where you stand when you’re making decisions about your own home. Here’s our guide to the current legislation and other factors worth considering.

Is Double Glazing compulsory?

What is double glazing?


To an extent, the clue’s in the name: double glazed window units are made with two panes of glass instead of one. It’s the air gap between these two panes that makes them so effective.


The air gap is filled with trapped argon gas during the unit’s construction. Due to its density and insulating properties, argon minimises heat exchange through the window, as well as minimising noise and reducing condensation – all highly desirable attributes for keeping homes cosy, peaceful and protected.

Is double glazing compulsory in the UK?


If you’re an owner or occupier who still has single glazing, don’t worry, the police won’t come knocking on the door. But as of April 2002, the UK government’s building regulations clearly outline that any replacement windows should be double-glazed. That means if you’re making changes to your home, you should be sure your new windows or doors are double glazed to comply with these guidelines. This legislation has been put in place to improve energy efficiency and the quality of life of residents.


Since April 2020, government regulations have further evolved in regard to landlords. Any rented properties must now have a minimum energy performance rating of E, whether or not there’s been a change of tenancy. A failure to meet these standards can result in a fine of up to £5,000. While this doesn’t directly enforce double glazing, replacing your windows is one of the most effective ways to increase energy efficiency, and will make a huge difference.

Follow these links for some additional guidance if you’re a landlord wanting to check your property meets MEES Regulations, or if you’re a tenant concerned about the home you currently live in.

Why do some houses not have double glazing?


Most houses that have single glazing were built before the government’s 2002 regulations came into effect. Older houses and period properties are more likely to have single glazing. 


New double-glazed windows are definitely an investment and will dramatically increase the energy efficiency of your property. However, it can seem like a big investment.


When considering the financial side of the decision, it’s important to look at the bigger picture. It may take a while for the savings on your energy bills to cover the installation costs, but those small monthly changes certainly add up in the long term – not to mention the added comfort and security you’ll enjoy in the meantime. 

Another worry that primarily concerns those who live in period properties is that replacing windows might compromise the building’s original character. Pair this with any additional complications with the installation process, and it can also be perceived as a job that’s much more costly and difficult than the final result is worth. Nowadays, there are more options to get around this than you think. Take a look at our heritage windows, which come in a variety of finishes and colours that include all the specs of modern windows while also being compliant with conservation and listed building regulations.

Are there disadvantages to double-glazed windows?


Cost aside, you may be wondering if there are any other downsides to making the switch to double glazing. To make an informed decision, there are a few more factors to weigh up.


The first relates back to period properties. Even after you’ve come around to the idea of changing the look of your home, the decision doesn’t solely lie in your hands. If the new windows look much different to what’s currently there, you’ll have to obtain planning permission – a process that can be tedious and lengthy. 

Then there’s the fact that they might actually retain too much heat. Even on Cornwall’s hottest summer days, this might sound crazy, but there are people who live in warmer climates that have no interest in making their home warmer than it needs to be. This is a rare concern for us here in the UK! 


It’s also worth noting that just as the initial cost is higher, any repairs to double glazing are likely to cost more, and be harder to carry out. For example, if the seal breaks, it could cause condensation between the panes – a problem so difficult to repair that it’s probably more cost-effective to replace the whole unit. An issue like this is easily avoided if the double glazing is installed by reputable professionals like ours in the first place. At CTG, all our windows are covered by a 10-year manufacturer’s warranty as well.


When do I need to replace my double glazing?


The tell tale signs that your double glazing is failing are water leaking through the frame, mist or condensation between the panes, cracks and chips in the glass, or cold draughts creeping into your home. 


Then there are the more subtle signs that emerge gradually, such as a reduction in thermal efficiency or soundproofing properties. No matter how well they’re installed, or how high quality the materials, there will come a time that this happens. The average lifespan for double glazing is about 20 years, or closer to 30 if they’re particularly high quality – so if you’re aware that this time is approaching, keep a lookout for any changes. 

Ready to make the switch? Our team will be happy to advise on the best options for your specific property, so feel free to get in touch – either online or by visiting our showroom in Hayle. We also have a number of online resources for you to check out at your convenience, like our brochures and our Design Your Solution feature.

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