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Trusted Traders

Cox Format Developments Limited

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26 Reviews

Opening Hours
Today - 07:30–16:30
  • Monday 07:30–16:30
  • Tuesday 07:30–16:30
  • Wednesday 07:30–16:30
  • Thursday 07:30–16:30
  • Friday 07:30–16:30
  • Saturday - Closed
  • Sunday - Closed


Cox Format Developments Limited is a professional building company. The majority of our work is through personal recommendations. We are always happy to show previous work and our customers are happy to let you look! We pride ourselves on quoting a good price and sticking to it. Unless you instruct us to, we never add on "extras" as some less reputable builders do as their standard practice.

Because we are professionals, we can see what work is necessary to achieve your objectives, and we price accordingly. Others may quote cheaper initially, then add on what they see as "unforeseen extras". We believe our work is cheaper for the client in the long run.

On Budget... On Time... Everytime.

More information can be found on our web site www.coxformat.co.uk or at www.facebook.com/cox.format
Please like and share our page.

What we do

  • Builders

    • Loft conversions
    • Extensions
    • Building services
    • Garage conversions
    • Log cabins and homes
  • Roofers

    • Chimneys
    • Flat roofing
    • Guttering, fascias and soffits
    • Lead work
    • Roof and skylights
    • Rubber roofing (EPDM)
  • Loft and property converters

  • Bathroom fitters

    • Bathroom design services
    • Bathroom refurbishment
    • Wet rooms
    • Bathroom Installation
    • Accessible bathrooms and showers
  • Damp proofing and timber preservation services

  • More Services

    • new build houses
    • velux windows

Customer reviews

26 reviews
Customer Service
Sort by
Amazing piece of work
Customer Service
The job was to build an extension at the rear of the house for a wet room next to the small kitchen involving removal of an old toilet block which in turn would give further space to the kitchen. Plans and any queries were thoroughly talked through by the team with ourselves beforehand and throughout the job. Important to us. Payment was done as each stage of the job was completed and our satisfaction assured. The builder - professional - and crew were very hardworking, thoughtful, polite and tidied at the end if each day. The end result was a piece of craftsmanship - a creation of space one could not have imagined. We would recommend Cox for your building needs.
Customer in Greater London Posted on 02/02/2020 , work completed 11/11/2019
Loft Conversion to en suite bedroom in Barnet
Customer Service
Well organised and good communication ensured a good job with minor issues promptly resolved. We are very pleased with the outcome and would recommend Cox Format to others.
Customer in Greater London Posted on 31/12/2019 , work completed 01/11/2019
Throrough and pleasant
Customer Service
We have had two lots of fairly minor repairs carried out by Cox Format, both were done very well by very pleasant workers - recommended.
Customer in Greater London Posted on 11/11/2019 , work completed 28/10/2019
Loft conversion and first floor bathroom remodel
Customer Service
We took our time to make a decision regarding building companies. With such a big project, we wanted to make sure we got it right. We could not be happier that we decided to go with Cox Format. The builders were all professional, courteous and respectful of ours and our neighbours' properties. They were always on time and tidied up at the end of every day. The foreman was clear in his communication and open to questions and concerns throughout the build. The project was completed on time, as projected, and we are beyond pleased with the quality of the work. No cutting corners, no "patch jobs"; they ensured that things were done right. Some companies may cost less, but you get what you pay for. I wouldn't hesitate to recommend Cox Format.
Angela, Greater London Posted on 02/07/2019 , work completed 01/06/2019
High quality work
Customer Service
We had an L-shaped, double dormer, loft conversion on our Victorian terraced house. The work was completed on schedule in 6 weeks, despite bad weather, and was of an excellent standard. The whole team were professional and very easy to deal with. There was clear communication between all of the Cox format team, the project manager and ourselves, and queries and changes were dealt with in a timely manner. There was a clearly laid out payment plan with transparent costings. We would thoroughly recommend the company.
Customer in Greater London Posted on 10/06/2019 , work completed 09/05/2019
Rear Extension
Customer Service
We recently completed an extension to the rear of our house. From the start of the design process through to the construction, Cox Format demonstrated professionalism, expertise and customer service with a clear passion for their business. It was clear from the start that their purpose was to ensure the clients expectations and satisfaction were met and put in the time and effort to ensure they met their goal. From start to finish the project went smoothly. We had regular meetings with the Project Manager to receive updates, review progress and discuss any changes. Any last minute changes were incorporated easily. The workforce turned up promptly every morning at 7AM and were respectful and trustworthy, and accomplished excellent work with paying attention to detail. Our home surroundings were protected to prevent any damage. We were impressed with the workmanship and speed with which the work progressed. The workplace was always left clean, tidy and safe at the end of the day. We've had an excellent experience with Cox Format and are very pleased with our finished product which was delivered on time and within budget. I would recommend Cox Format as our expectations were highly met and simply, quite stress free due to their organised and dedicated approach to their business.
Customer in Greater London Posted on 01/05/2019 , work completed 14/12/2018
Great company with a lot of experience.
Customer Service
We chose Cox Format to do our loft conversation because they're Which? Trusted Traders and we wanted a loft conversion done that required lowering some ceilings to make room. Cox's team were excellent at managing all aspects of the conversion, from completing the council paperwork, to providing detailed quotes and timelines. Mark, Project Manager, took into account all of our requirements and provided a lot of flexibility with additional tasks that we wanted done, such as custom spotlights and additional electrics. He also provided us with a timeline of work to help us manage expectation. A major plus was how quickly and professionally they built the loft, choosing additional manpower instead of sacrificing quality. We were able to see everything as it progressed, and the builders were happy to answer all of our questions. Everything was solidly built, finished, and plastered to a high degree. Both the builders and the subcontractors involved worked to a high standard while taking care of our house. Cox gave us an estimate of eight weeks to do the loft conversion. Eight weeks later the loft was complete and Cox Format delivered us the Final Certificate to show that it had passed all inspections. The build went smoothly, and we highly recommend them to anyone who wants a hassle-free loft extension.
Customer in Greater London Posted on 18/04/2019 , work completed 05/04/2019
Ground Floor Rear Extension and Kitchen/Dining Room remodel
Customer Service
Our project was to extend and completely remodel the back half of our terraced house. Cox format delivered the job to time and cost once our requested extras where factored in. They even managed to work around our daughters A Level revision timetable All work was professional and of high quality - we liked how tidy the work site was left each night Mark kept us informed throughout with regular updates and site meetings.
Customer in Greater London Posted on 18/04/2019 , work completed 05/10/2018
Design and Build Loft Conversion
Customer Service
We engaged Cox Format to design and build our dormer loft conversion. They made well thought out plans with our input and took care of the planning permission and the subsequent appeal. They communicated the start date and from then on were at work solidly until they finished. Arriving everyday without fail at 0730 and getting straight to work. Starting at this time allowed us to discuss and take any decisions the team needed before leaving for work ourselves. The team were well presented, professional, polite and hard working, paid good attention to detail and always tidied up before leaving for the day. The back office staff produced a detailed quote and payment plan with an itemised list of any additional payments. I would absolutely recommend Cox Format for your loft conversion.
Customer in Hertfordshire Posted on 25/01/2019 , work completed 21/12/2018
Stress Free Builders
Customer Service
Cox Format have just finished an extension for us and it is excellent! When looking for a suitable builder we were seeking quality of workmanship, timeliness, cleanliness, friendliness and real value for money. Cox Format delivered all of these. They kept us well informed as the work progressed and listened when we sought any clarifications. They finished on time and to cost. We felt at ease throughout the whole build. All I can say is that I would recommend them without hesitation.
Customer in Greater London Posted on 17/12/2018 , work completed 10/12/2018