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Double Glazing Installers In Essex

Replacement Windows, perfect for your period property or your conservatory refurbishment

Expertly-designed windows add so much more than a gleaming finishing touch to your home. Security and energy-efficiency are vastly improved, which in turn help you save money on your heating bills.

With our A++ rated, double-glazed windows manufactured from industry-leading composite materials, you can also relax in the knowledge that they won’t distort or crack.

Based in Southend-On-Sea, we provide quality services to clients based in Westcliff-On-Sea, Rayleigh and all areas within a 5 mile radius of our showroom. Get in touch with Greenoak Concept & Design Ltd for more information on all window solutions.

Group 9
Casement Windows
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Vertical Sliding
Group 9
Flush Sash Windows
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Tilt & Turn Windows
Group 9
Bay & Bow Windows
White Windows

A Range Of Styles For Your Home

Casement Windows

Open outward to promote excellent ventilation and come in various styles to suit any property.

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Flush Casement Windows

Modern twist on the classic. Seamless design with improved weatherproofing, ideal for contemporary aesthetics

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Bay & Bow Windows

Create a beautiful extension of your living space. Offer panoramic views and increased natural light.

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House with wooden window and door frames After
House with white window and door frames Before
Our window range come in three styles, sculptured, chamfered and flush, all can be viewed on our brochure page or in our showroom.
Greenoak Concept & Design has two preferred UPVC window system Liniar & Deceuninck which we believe are by far the leading window extrusion on the market to date.

Their chamber systems provides better insulation, strength and acoustic performance which is constructed and made from 100% lead free PVCu.

The bubble gasket gives an enhanced weather seal, which offers less chance of warmth escaping and no noisy drafts.

Both system has achieved a BFRC (British Fenestration Rating Council) window Energy rating of “A”, the highest achievable. Greenoak supply “A” Rated Argon gas filed double glassed units as standard, making our windows the most efficient on the market.

Deceuninck logo
Greenoak Concept & Design

All windows come with

Bespoke service
with a genuine smile

Greenoak Concept & Design Ltd provide a comprehensive selection and installation service to ensure that your new double-glazed windows look as good as possible.
Taking direction from your vision, our dedicated team will guide you through all of the design options available to you and how they might fit into your home Once you are happy with your choice, Greenoak Concept & Design Ltd.’s expert fitting team delivers a seamless installation service, ensuring that you are 100% satisfied with your new double-glazed windows, both now and in the future.
The Greenoak Concept & Design Installations team actively work with some of the best systems companies and industry innovators to guarantee an impressive finished result every time. These include household names like Linair, Alumina, Korniche, Solidor, Hurst, Pilkinton, Masterdor and Ultraframe, delivering excellent efficiency, security, and style.

The perfect finish

Our standard white is a high gloss finish, making it easier to keep your new windows bright and white for years to come.

Many other systems have a matt, grainy finish, which the dirt will cling to, making it much harder to keep clean.

If white isn’t what you’re looking for, we have a wide range of colours and wood finishes, What about smooth cream or white woodgrain? The choice is yours…

Frequently Asked

If you have any questions in relation to our double glazing services, then look no further. This FAQ section answers some of the most common questions we come across. If what you had in mind is not mentioned here, please don’t hesitate to contact us and we will be happy to answer any question you may have.

Planning permission is not required to install double glazed windows, unless the property is a Grade 2 listed building or in a conservation area.

Prices can vary depending on the size, style, design and quantity. If you require a quote, contact Greenoak Concept & Design Ltd, providing as much information as possible and we will be more than happy to provide you with one.

The time of double glazing installation can vary depending on the size of the property. On a rough guide, a fully detached house of windows can take on average up to one week.

At Greenoak Concept & Design Ltd, everything that we do and our company guarantees are insurance backed. All windows are covered via Greenoak Concept & Design Ltd and are backed via Certass, the industry regulation building control.

Installing double glazed windows can bring many benefits to your home. From energy efficiency in all weather conditions and the reduction of noise pollution to added security, our double glazing solutions are second to no other.

We're trusted within our industry
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Based on 56 Reviews

Good original consultation with Dale, general advice without being pushy. Survey efficient and quote broken down and understandable. Very good team from Greenoak, work done as per schedule, clean and tidy. Very considerate when one of us was unwell, kept the noise down. Problem with garage door investigated and rectified very quickly. Really pleased with final result, completely transformed external appearance of house. Thanks to whole team inc Tom Jay Mike Dave Callum Ed and esp Mark and Tegan.

Kitty Heyns

Amazing service from start to finish. Wouldn't go anywhere else, highly recommend to anyone.

Danny Clark

5 * very helpful and professional great service 👍 👏 👌 highly recommended.

Roman Clark

This my second time using Greenoaks Conecept and design , I cannot vouch for them enough ! Dale and the team completed a very a high standard of work throughout on a few properties for me and would highly recommend to anyone looking .


Dale and his team are amazing! I will use them again!

Mary Dean

Highly recommend this company. Had our conservatory roof done and they did a fantastic job. They kept us informed every step of the way of what would be happening. Cleaned up at the end of each day and was very hardworking, polite and friendly.

Dale has been a star. From his first visit to give me a price, to completion of the works. Punctuality and communication of the Greenoak team (Dave/Ray/Callum) was excellent.I am so pleased with the job that Green Oak have completed for me. They were professional, tidy and worked so hard. The job is finished to a high standard and I will 100% use them again. Would highly recommend.

Maria Howe

Job was done in the hours I was told. Very efficient and happy with my new conservatory roof. Thank you and would happily recommend Greenoak

alan shinn

We recently had relacement windows and doors by Greenoak Concept. Many thanks to Dale and all the team,they are very professional, punctual, polite and leave the job in a clean and tidy condition. Very pleased with the outcome, many thanks to all at Greenoak.

Dale and the Greenoak team are fantastic; having delivered 2 large projects on our house, both on-time and on-budget (and with a laugh & smile!) we can’t recommend them enough! Thank you!

Professional job.

Nick Brennan

So far very happy with the installation . Our tired old conservatory has been totally transformed by the team at Greenoaks. They worked cleanly and efficiently whilst navigating our day today running if the house. We’re actually looking forward to the heat of summer and cold of winter!!

Dale, you and your team, thank you so much for your time and dedication. Our new composite Rock door looks and feels fantastic. It feels really good using a local company that cares about their customer from start to finish. Thank you

We have had a solid roof put on our conservatory by Green Oak. We were very impressed from the outset. Dale took time to explain every aspect of the build bringing a model of the roof so we could see the construction. Then he left us think about it and there was no hard sell. The workmen were very pleasant, friendly and worked extremely hard. Despite being one man down the other chap worked late into the evening to make sure the construction was finished on time ( rather than have to come back for a couple of hours the following day), as did the man doing the plaster boarding. Every evening the site was left tidy and all rubbish taken away once the work was finished. The plasterer and electrician also did a brilliant job and all works was finished on time. We are really happy with the end result and couldn’t recommend the firm more highly. John & Rita Dobinson

Nicky Boosey

Dale was very professional in giving us sound advice and explained the whole process from start to finish. The job commenced on time, Mike and Mark treated our home with respect and were very knowledgeable and kept us informed all the way along. The quality of work is excellent and we would recommend them.

Ian Creek

We needed 11 new windows of various sizes so we spent some time searching reviews for a highly rated but local Double Glazing window installer. Greenoak came out top of our search results, We reached out and Dale responded quickly followed by a visit a few days after. The resultant quote was very competitive versus other quotes we had received. It was an easy decision to go with Greenoak. Dale came across as very knowledgeable, friendly and genuinely customer focussed. He invited us to the showroom in Leigh where he took us through the detail to ensure we were fully aligned on requirements and expectations. We were very impressed with him and his business and by his overall professionalism. The installation took place on 20th Feb 2023 and took 4 days in total. The whole process was exemplary, we could not fault the team in any way. They were tidy, considerate and very thorough. We have had windows fitted before by various other company's but the quality of fit and finish from the Greenoak fitters was far superior. The guys worked solidly and clearly did not skimp on anything, ensuring that the windows were not only properly fitted but sealed professionally too. They did an outstanding job including clearing all of the old windows and rubbish Overall we'd rate Greenoak at 10/10. We felt reassured by their high standards of work ethics, integrity and customer satisfaction. We honestly doubt there is anyone better out there for this type of work. We therefore wholeheartedly recommend them Ian and Jenny

Fantastic job done by Greenoak, the guys were professional, friendly and a pleasure to have in my home. I couldn’t be happier with the job they did. Highly recommended.

Brilliant company, very friendly and easy to work with. Very pleased with the finished cladding on our office wall - excellent quality and good value


Replacement Conservatory Roof. Fantastic company and service from the whole team! Dale is great and gave me a quote for my new lightweight roof, great bloke and not pushy, loved the fact he gave a all in price rather than start low and add extras. The fitting team are fantastic!, Mike, Mark and Casper treated my home like their own, , great attention to detail and did everything I asked to get the perfect finish, I honestly cant find 1 fault and I am fussy! I could not be more happier with my roof!! Take my advice, Don't look anywhere else ,I cant rate them highly enough. Greenoak are the BEST!

Following our initial discussions with Dale, our expectations were already set high when it came around to installation. Some truly awful weather right at the start of the installation virtually wiped out the first two days work, and the anticipated seven day build seemed to be in jeopardy right from the start. But Mike and his crew - supplemented by two and sometimes three others, working in still inclement weather, brought the build back on schedule by the end of day five, and the plastering and electrical second fix over days six and seven meant the whole project was delivered to time, and budget meaning that our initial high expectations had even been exceeded. I have nothing but the highest regard for their workmanship and scheduling - and not forgetting Dione in the office who kept me informed throughout and efficiently managed the stage payments. In my experience it is unusual to receive a great sales pitch and then to have that exceeded by the installation teams - I couldn't recommend Greenoak's services more highly.

Our team are
ready and waiting
to help you...

Greenoak Concept & Design have been raising the standards for more than 10 years.

More about us: We’re an independent Essex-based specialists in high quality UPVC Windows, Doors, Tiled Conservatory Roofing, Wall Cladding, and Fascias, Soffits and Guttering.


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