The 6 best UK double glazing companies in 2024 Written by Tom Gill Updated on 7 March 2024 ✔ We’ve researched extensively to find the best double glazing companies for you✔ We settled on seven of the best double glazing companies across the UK✔ Double glazing saves you money and improves your home’s efficiencyDouble glazing is one the most effective ways to improve your home’s insulation.Between 18% to 30% of heat is lost through windows and doors, but these figures can be significantly reduced by installing double glazing.It’s no wonder roughly 88% of households in England have it.But given the high cost of double glazed windows, you want to make sure you choose an installer who’ll get the job done properly, all while giving you a fair price.With so many options to choose from, picking an installer can be daunting.That’s why we’ve done the research for you, by analysing nearly 250 UK double glazing companies. We looked at the top local and national providers, and picked the best ones.We focused on the installers’ expertise and credentials, and what real customers have said about their experience in reviews from accredited websites.Want to skip the reading and start comparing double glazing prices? We can help — fill in the form with a few details about your home, and we’ll put you in touch with our expert installers. They’ll get back to you with bespoke double glazing quotes for you to compare.What’s on this page? 01 How we chose the best double glazing companies 02 The best double glazing companies 03 Table of results 04 Next steps 05 FAQs How we chose the best double glazing companiesOur team of four researchers spent 28 hours investigating double glazing companies to find the top seven companies across the country.We focused on the best companies across the UK’s 124 postcode areas, looking at seven key factors: customer satisfaction, warranties, finance options, window choice, security, ability to preview finished product, and affordability.Understand the costs of adding double glazing to your property by comparing double glazing prices from various suppliers.WarrantyDouble glazing is a home improvement that needs a solid warranty to protect you from the unavoidable wear and tear your windows will experience.We worked out the average warranty offered by double glazing companies, which was 10 years, and looked at which companies offered longer warranties.Finance optionsNot everyone wants to pay the full upfront cost for double glazing, so we compared finance options to see which companies offered the best combination of ease of repayments, quality of the product, and finance flexibility.ChoiceHaving lots of choice when picking double glazing is important, because it’ll be a part of your home for potentially decades. We analysed companies based on available frames, materials, and whether they offered customisable window shapes.SecurityDouble glazing naturally adds more security, but we wanted to see what companies offered an extra layer of protection for peace of mind. We looked at additional security options including complex locking mechanisms, reinforced glass and frames, and break-in guarantees.Previewing finished productIt’s important to get a clear picture of what double glazing will look like after it’s been installed, so we covered companies using technology such as virtual reality to give customers a preview.AffordabilityFor affordability, we didn’t just look at which companies had the cheapest windows overall. We considered both cost and quality, looking at the companies offering double glazing that’s great value for money. The best double glazing companiesFor our tests, we distilled more than 28 hours of research to find the best double glazing company in each category.The seven top companies are:Everest – Best for finance optionsClearview – Best for warrantyAnglian Home Improvements – Best for choiceFirst Home Improvements – Best for securityCR Smith Windows – Best for previewing the finished productBritelite – Best for affordabilityBest for finance options: EverestDouble glazing can be expensive, with the average cost of double glazing being £640 per window. That can make financing options very attractive for a lot of households, who want to benefit from double glazing — and all the energy savings — without paying the high upfront costs.Everest offers one of the best financing options in the business, with customers able to spread costs across a hugely impressive 180 months (15 years). It’s a good deal better than the three to five year finance options typically offered by most double glazing companies, and the fixed interest rate of 11.9% makes payments easily manageable.This means a double glazing project that costs £5,000 would see you paying back just £51.87 a month, plus an initial £500 deposit, for a total cost of £9,336.70 after 15 years.Find out how much double glazing might cost you with our double glazing cost calculator.Pros and consPros:Good security with GrabLock featureA+ energy efficiency, the second highest rating for double glazingExcellent finance optionsCons:Expensive compared to other companiesAdditional furnishings can increase the cost quickly What type of double glazing do you need? Aluminium frame uPVC frame Wooden frame Other / not sure Get started Best for warranty: ClearviewYour average double glazing guarantee is around 10 years, which is a pretty generous amount of time considering the typical double glazed window lasts between 25 and 30 years.Clearview, on the other hand, looked at that number and thought “yeah, we’ll double that.”Its 20-year guarantee is industry leading, which is probably why Clearview won the G Award in 2022 (the annual award celebrating and rewarding excellence in the UK glass and glazing industry).Clearview is clearly confident enough in the quality of its windows, because of all the major double glazing companies we investigated, no others offered a 20-year warranty.There is a catch though, including the fact that, if your window breaks, you’ll still have to pay a portion of the labour costs after the first 10 years.Pros and consPros:Longest warranty period on the marketAward-winning windowsPlenty of styles to choose fromCons:Only available in Cheshire and LancashireBest for choice: Anglian Home ImprovementsAnglian Home Improvements have more than 55 years in the business, and with that experience comes a lot of versatility.It’s a company capable of delivering any type of window you’d want, whether it’s stylish sash windows for a townhouse, or classic timber frame windows for a cottage (or even a listed building).If you need a custom shape, Anglian Home Improvements are more than capable too. Examples on its website include curved, circular, square, or triangular – but Anglian stresses that there’s no limit to what shape you can choose.This flexibility is ideal for homeowners with properties that have unique aesthetics and want windows that really stand out.Pros and consPros:Huge variety of materials and stylesNationwide installerWidely accredited by FENSA, the Glass and Glazing Federation, and TrustMarkCons:Some reviews mention poor communicationBest for security: First Home ImprovementsDouble glazing already adds an extra layer of security to your home — especially uPCV windows — but there’s nothing wrong with being even more secure.First Home Improvements certainly think so, which is why it prioritises security as one of its key selling points. All windows from First Home Improvements come with locks built by Yale, though the pièce de résistance is the patented Blade Lock.The Blade Lock is what makes windows by First Home Improvements the go-to option for homeowners particularly concerned about window safety. Its design has three times more contact between the sash and the frame of an ordinary window, making it a lot stronger than most double glazing frames.In testing, the Blade Lock was all but impregnable by ordinary means, and independent examiners couldn’t pry the windows open even using hydraulics. Put simply, neither your opportunist robber or organised criminal is getting through your window easily.Pros and consPros:The strongest window locks on the market12-year window and lock guarantee, longer than most installersCons:Limited to Midlands, East Anglia, and southern EnglandNot accredited by Secured by Design, the official police security initiative Best for previewing the finished product: CR Smith WindowsGlossy photos and the power of your imagination can only go so far — sometimes you want to actually see what your home will look like with your chosen window design. CR Smith Windows makes that possible with its innovative 3D design service.You’ll get a 3D rendering of your home with your new windows installed, so you’ll be able to actually visualise the finished product. This is a near-foolproof way to avoid buyer’s regret, because it’s a fact of life that sometimes, once something is installed, you’re just not satisfied.CR Smith Windows even lets you explore a fully immersive virtual reality animation of your home, so you get a real sense of how it’ll all come together. And if you’re not happy with the digital preview, a consultant will be on hand to suggest alternatives.The only significant downsides to CR Smith Windows is that it’s a Scotland-only company, and you only have the choice of either uPVC or timber windows. This basically means choosing between both the cheapest and most expensive ends of the window spectrum.Pros and consPros:3D previews of your home, a rarity98% satisfaction rate on Which?Security guarantee — any window frame broken by intruder will be replaced for freeCons:Only available in ScotlandLimited material choiceBest for affordability: BriteliteIf you want quality double glazing on a budget, Britelite is your best bet. Typical prices for a uPVC casement window are substantially lower than other installers on this list — £160–£450, on average, compared to £500–£1,230 for Everest.Britelite still guarantees A+ efficiency for its windows too, which means you’re getting almost exactly the same energy-saving benefits, just at a fraction of the cost.The company has all the expected certifications for a high-profile double glazing company as well, so you won’t need to worry about getting a botched product because you’ve spent less. That should go some way to assuage concerns that cheaper double glazing automatically means worse double glazing.However, you’ll be limited in your material choices, as Britelite only offers uPVC, composite, and aluminium window frames. Style choices aren’t hugely varied too, with casement, sash, and tilt & turn being the only ones available.Pros and consPros:Affordable windowsTransferrable guaranteesBacked by industry-recognised organisationsCons:Limited material choiceOnly a few styles available Table of resultsHere’s an overview of the best double glazing installers: 0 out of 0 backward forward Company Customer satisfaction Warranty Finance options Choice material Security Previewing finished product Affordability Best for customer satisfaction Safestyle Best for warranty Clearview Best for finance options Everest Best for choice Anglian Home Improvements Best for security First Home Improvements Best for previewing finished product CR Smith Windows Best for affordability Britelite 4.1/5 (44,949 reviews) 4.3/5 (1,210 reviews) 4.3/5 (12,368 reviews) 3.9/5 (29,684 reviews) 4.4/5 (3,340 reviews) 4.9/5 (3,449 reviews) 4.1/5 (1,332 reviews) 10 years 20 years 10 years 10 years 10 years 10 years 10 years Buy now pay in 12 months 13.9% APR representative 120 monthly payments at 11.9% APR representative 120 or 180 months at 11.9% APR representative 36 months at 11.9% APR representative Enquire for loans 36 months at 2.9% APR representative 60 or 120 months at 11.9% APR representative uPVC uPVC and aluminium uPVC, timber, aluminium uPVC, timber, aluminium uPVC uPVC, timber, aluminium uPVC, composite, aluminium Multi-point locking system VAULTBOLT locking technology GrabLock technology Secured by Design accredited Blade Lock technology Secured by Design accredited Secured by Design accredited n/a n/a n/a n/a n/a 3D virtual reality scan of your home n/a £250–£1,050 per window £175–£680 £500–£1,230 £249–£999 £200–£750 £250–£895 £160–£450 Next stepsThe number of double glazing companies in the UK can seem overwhelming, so hopefully we’ve helped you feel more confident in picking the right company.If you’re still unsure, we can help you compare double glazing quotes with our easy-to-understand form. Once you’ve entered a few details about your home, we’ll connect you with our trusted installers who’ll get in touch with bespoke quotes to compare.If you’re looking to let some light in through a window in your roof, take a look at our guide to buying skylights and rooflights. FAQs Who are the best window makers in the UK? Best for warranty — ClearviewBest for finance options — EverestBest for choice — Anglian Home ImprovementsBest for security — First Home ImprovementsBest for knowing what the finished product will look like — CR Smith WindowsBest for affordability — Britelite What is the best material for double glazing? The best material for double glazing depends on what’s most important to you. If you want a long-lasting, high-security window frame, go for uPVC because its durability is unparalleled. If you want a traditional frame that suits the aesthetics of older properties, opt for timber, which can look truly spectacular. For affordability and excellent insulation, aluminium frames are a great choice and they can last up to 30 years. When should I replace double glazing? The typical lifespan for double glazing is 15–20 years, so when your windows reach this age, it’s a good idea to think about replacing them. Of course, not all double glazing is like this and you’ll find some installers list a lifespan of up to 30 years.You can still keep an eye out for the tell-tale signs that your double glazing needs replacing, which include:Noticeable draughts around your windowsVisible chips or cracks along the window or frameCondensation forming between the window panesWater leaking in from the outsideDifficult opening and closing your windows How do I find the best double glazing company? When searching for a double glazing company, keep an eye out for important accreditations. These include FENSA, a government-authorised scheme that monitors building regulation compliance for replacement windows, and whether the company is a member of the Glass and Glazing Federation.TrustMark Registered Business is another one to take note of, as this means the double glazing company has been thoroughly vetted to meet high standards (excellent customer service, technical competence, and trading practices). Written by: Tom Gill Writer Tom joined The Eco Experts over a year ago and has since covered the carbon footprint of the Roman Empire, profiled the world’s largest solar farms, and investigated what a 100% renewable UK would look like. Tom has a particular interest in the global energy market and how it works, including the ongoing semiconductor shortage, the future of hydrogen, and Cornwall's growing lithium industry.