Extension builders in Isleworth

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.3 (23 reviews)

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Some of our top rated extension builders in Isleworth

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Renovaze LTD
Rating: 5 out of 5
Extension Builder in Isleworth
0% Finance Now Available. Spread the cost of our services today! Welcome to Renovaze. We Build extensions and carry out Full property Refurbishments including Bathroom design & Installation, Shower room design & installation and Kitchen installation. We are Clear, Transparent and Act with Integrity. Our huge reputation in providing excellence ensures you have peace of mind throughout the Project Journey. Get in touch and let us Renovate and Amaze you!
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Latest review:
Bathroom Fitting- 25 Jan 2022
Happy with work done to quality and agreed time line. Good communication throughout the 3 day job. Happy to recommend to others.
Wader construction
Rating: 5 out of 5
Extension Builder in Isleworth
Over 30 years of professional bricklaying experience, I specialise in all aspects of brickwork, blockwork, stonework, brick slips, repointing, repairs, extensions, garden walls, fences, RC frame masonry, masonry support systems, paving and slab laying, and general masonry construction. I take pride in delivering high-quality craftsmanship, attention to detail, and reliable service on every project. Whether working on residential, commercial, or heritage developments, I am committed to achieving exceptional results and ensuring complete customer satisfaction. Services Include: Brickwork & Blockwork Stonework & Brick Slips Repointing & Repairs Extensions & New Builds Garden Walls & Boundary Walls External wall insulation system Silicone and acrylic render. RC Frame Masonry Masonry Support Systems Paving & Slab Laying General masonry works. Refurbishments
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Latest review:
Insulation- 6 Oct 2026
Absolutely fantastic, I cannot recommend this company enough, really top quality work, friendly and professional and went above and beyond to finish the job to a extremely high standard, I personally will recommend them to friends and neighbours. They boarded up some eaves storage for me, it had tricky small access but this didn’t put them off, and I’m so pleased with the results. Great communication and clean and tidy on the day. Darius was fantastic.
Ekon Building LTD
No reviews yet
Extension Builder in Isleworth
With over 15 years of experience, we are a premier London-based construction company specializing in full-scale renovations, bespoke kitchens and bathrooms, extensions, and loft conversions. From initial design to completion, we deliver high-quality craftsmanship, reliable plumbing and electrical services, joinery, and landscaping. We are committed to excellence, delivering tailored solutions that bring your vision to life within budget.
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WS Building
Rating: 4.8 out of 5
Extension Builder in Isleworth
I am Builder with 30 years experience in all kind of building projects.Together with my team we can provide for you a complete building service and help with advice in any aspects of building works. We specialise in: conversions, extensions, renovations, reconfigurations, basements, lofts, new kitchens and bathrooms, flooring , doors, gardening, demolition works, roofing, steel installation, plastering, painting and decorating and all others of building works included electric and plumbing.
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Latest review:
Restoration & Refurbishment- 10 Nov 2025
Professional and on time, recommended
Jwolfconstruction ltd
Rating: 5 out of 5
Extension Builder in Isleworth
My name is George and I'm running J Wolf Construction building company. I can provide a lot references from happy customers in sw London.
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Latest review:
Extensions- 26 Nov 2019
Great on delivery, good on project management....rate them very high on integrity and transparency
Jpsingh
No reviews yet
Extension Builder in Isleworth
Good price good quality
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CCM CAPITAL CONSTRUCTION LIMITED
Rating: 4.8 out of 5
Extension Builder in Isleworth
All construction work
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Latest review:
Bathroom Fitting- 30 Nov 2025
Mohsen and his team are very professional workers. They communicated clearly with me during the quoting process and were very helpful. They replaced my shower tray and shower screen beautifully and exceeded my expectations. Highly recommend their work!
B Bespoke Design & Build Ltd
No reviews yet
Extension Builder in Isleworth
Welcome to B Bespoke Design and Build Ltd, with over 40 years of experience delivering exceptional projects. Our expertise spans across a diverse range of residential and commercial developments, ensuring high-quality craftsmanship and attention to detail in every build. We have successfully built over 13 new properties, ranging from modest dwellings to luxurious mansions, all designed and constructed to the highest standards. Moreover we have completed numerous extensions / loft conversions that seamlessly integrate with existing structures, enhancing both functionality and aesthetics.
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FM Building
Rating: 4.8 out of 5
Extension Builder in Isleworth
Honest and friendly company, we here at FM Building focus on complete customer satisfaction and make a promise to our clients to offer best quality services at competitive rates. All projects considered and dealt with in a professional manner regardless of the size or duration.
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Latest review:
Handyman- 12 Oct 2018
The flat was left in a very bad state after the tenants left. Marius was able to undertake all the jobs, from changing carpets, redecorate, repairs and clean up. Also gave good advice as I was not able to attend the site in person so Marius kept me updated with photos. The price was also good. Thank you. Will use these guys again.
GURRA CONSTRUCTION LTD
Rating: 5 out of 5
Extension Builder in Isleworth
Kitchen & bathroom refurbishment Electrical work Extension Full refurbishment
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Latest review:
Carpentry- 20 Mar 2022
Very reliable & jeen to work
Maxmar Construction Ltd
Rating: 4.7 out of 5
Extension Builder in Isleworth
We are a company that pride ourselves on taking excellent care of the ‘whole project’, from design to completion. We can, on your behalf, manage your project, coordinating all the required trades to turn up as and when required, leaving you to get on with daily life. Your dream home could be closer than you think, allow us to turn your ideas into reality. My company has lots of experience working on many different projects, big or small! On a personal level I am a honest hardworking individual. I have a lot of experience in all aspects of building work. I am familiar with building regulations and used to dealing with building control officers from the various local authorities. I have a fully skilled team of builders who cover all types of general building maintenance including kitchen and bathroom fitters, plasterers, flooring specialists, painters and decorators. The company offers a fully insured and guaranteed comprehensive
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Latest review:
Conversions - General- 21 Jul 2013
Flooring & lighting to extension not completed appropriately and resulted in later problems.
Gotbath UK Ltd
Rating: 4.7 out of 5
Extension Builder in Isleworth
Gotbath UK Ltd is London based family construction company committed to deliver an exceptional service on budget and time. Whether you require an extension, loft conversion or remodelling an existing property, we provide a full service. We work together with profesional as architects, designers, engineers etc
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Latest review:
Extensions- 20 Feb 2020
Decent builders but with extremely poor communication skills. First the good points: 1. They are good at internal finishes 2. They create and use a Statement of Work (SOW) to track all costs of the project, so there were no major surprises in the project 3. They are friendly and hard workers - who arrive on time Gotbath UK Ltd used subcontractors to build us a 6 meter rear extension. Although they had an in-house architect, they did not know the law around boundaries which resulted in a conflict with our neighbours. After spending hundreds on hiring a boundary surveyor, the initial wall had to be re-built within our boundary. Gotbath did not take any responsibility for the wrong information they provided to us regarding boundaries and charged us for the rebuild. When discussing how to finish the inside of the extension, GotBath were extremely slow in ordering supplies and in general responding to us, so we took matters into our own hands and ordered materials ourselves which were removed from the SOW provided to us. At the end of the project, finishes took a long time and required constant chasing. Final gas, electrical and warranty documents took a long time to reach us and required a lot of chasing too. I have very little confidence that GotBath will honour the warranty document they have provided to us. It's a shame because I can see GotBath have a lot of potential as a builder. However, their lack of communication has really let them down.
Stevobrickwork
No reviews yet
Extension Builder in Isleworth
Up and coming Brickwork company with experience in commercial and residential builds, with desire to build your work to highest standard with positive Attitude
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Strongwell Construction LTD
No reviews yet
Extension Builder in Isleworth
We are an experienced family-run construction team specialising in extensions, renovations, and new builds. With years of hands-on expertise, we pride ourselves on delivering high-quality workmanship, attention to detail, and excellent customer service. From the first consultation to the final touches, we work closely with our clients to ensure every project is completed on time, on budget, and to the highest standards. No job is too big or too small — your satisfaction is our top priority.
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fta haliti ltd
Rating: 5 out of 5
Extension Builder in Isleworth
FTA construction is a family run company that specialises in, Design and build projects inc, extensions, loft conversions, interior and exterior inc plumbing and electrician
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Latest review:
Driveways (Paved & Loose)- 1 Jun 2019
That’s was lovely job from ur company,well done guys ,highly recommended your company,very professional and tidy.Very happy with your company
FLV PROPERTY LTD
Rating: 5 out of 5
Extension Builder in Isleworth
At FLV property ltd we are a team of skilled professionals with extensive experience in the construction industry for over 30 years. Whether you are planning a new build, an extension, a renovation or bespoke projects, our expertise ensures that every job is completed to the highest standards on and within budget. What we offer; •A team of dedicated professionals •Architects •Structural Engineers •Surveyors •Multi skilled tradesmen Attention to detail from design to composition. Our promise; We understand that building projects are significant investment's, and our goal is to make the process as smooth and stress free as possible. From initial consultation to project completion, we work closely with you to ensure your expectations are not only met but exceeded. LETS BUILD TOGETHER!
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Latest review:
Gus and Frank were brilliant. Their attention to detail and care for our project was evident. There was already an issue with our floor which Gus and Frank rectified for us before doing the tiling. The final finish was immaculate. We liked their work so much that we also got them to fit our kitchen worktop. Good communication and clarity throughout the job. Would definitely recommend!

4.3

Top rated Extension Builders

Our Extension Builders in Isleworth, are rated 4.3 out of 5 based on 23 reviews from customers like you.

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What types of services are offered by local extension builders in Isleworth?

Building an extension is a major milestone for any home. It’s not just about adding extra space, it’s a big step that can transform how you live day to day, opening up new possibilities for comfort, lifestyle, and family needs.

This is why it’s so important to find the right extension builders in Isleworth for you. They can help with a variety of tasks and projects, including:

Extending your home with an extra room
Two+ storey extensions
Adding partition walls to create more rooms
Building annexes or external structures

To find the right extension builder near you, simply post your job on MyBuilder. Explain the type of help you’re looking for, and then home extension builders in Isleworth who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Isleworth extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Isleworth?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Isleworth will charge between £16 and £42 per hour.

Single-storey rear extensions cost between £20,000 and £60,000 depending on size and finish.
The cost of double-storey extensions, which add more space and value, can range from £100,000 to over £170,000.
Larger wrap-around extensions that combine multiple extension types can range from £40,000 to over £120,000.

The cost of an extension will vary depending on your property. For instance, extending in certain areas may require structural adjustments to ensure stability, which can increase your material and labour costs.

To get an accurate price for your home extension, request detailed quotes from several Isleworth extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Isleworth home extension project is likely to cost.

Find extension builders in Isleworth with MyBuilder

Hiring the right extension builder in Isleworth with MyBuilder couldn’t be easier. Just follow these simple steps:

Step 1: Post your extension project on MyBuilder

Whether you’re planning a single-storey extension, a loft conversion, or adding a new room, post your job on MyBuilder to find local Isleworth extension builders. Once your job is live, we’ll share it with home extension builders in Isleworth who can express their interest.

Step 2: Compare different extension builders in Isleworth

When you start receiving interest, review profiles of local Isleworth extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Isleworth extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Isleworth, compare their experience, guarantees, and costs before choosing who to hire.

You’ll also have confidence knowing that every tradesperson on MyBuilder is verified through several checks, including:

ID verification: When a tradesperson joins MyBuilder, we ask for a valid ID, such as a passport, ID card, or eIDAS certificate.
Company verification: For tradespeople operating under a company, we make sure every tradesperson has a registered business.

Did you know? Our continuous monitoring and complaints process ensures that tradespeople who don’t meet our standards are promptly removed from MyBuilder’s platform.

Isleworth extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Isleworth extension builder before hiring?

Before hiring an extension builder in Isleworth or extension building company in Isleworth, ask a few key questions to make sure you’re choosing the right professional for your home extension project.

What qualifications and experience do you have as an extension builder in Isleworth?

An extension builder in Isleworth should have a strong track record with similar projects and relevant building qualifications or trade memberships, such as the Federation of Master Builders (FMB) or TrustMark.

Will my home extension meet all building regulations and planning requirements?

Your Isleworth extension builder should ensure the project complies with Building Regulations and, where necessary, handle or assist with planning permissions. Ask how they manage building control inspections and what documentation you’ll receive once the project is complete.

What experience do you have with similar extensions in Isleworth?

Ask to see examples of their previous work, or view examples of their work on MyBuilder. Ideally projects similar to yours in scale and design. This helps you assess the Isleworth extension builder’s ability to deliver a result that meets your expectations.

How long will the extension take to complete?

Extension project timelines can vary depending on size, complexity, and weather. A typical single-storey extension might take around 8 - 12 weeks. Request a detailed schedule so you know what to expect and when key milestones will be reached.

Do you offer a guarantee for your work? Most Isleworth extension builders offer a guarantee or warranty on their work, often between 1 and 10 years depending on the project and materials used. This gives you assurance that any issues will be resolved after completion.

If you still have questions about the professional you are looking to hire, we have a full detailed guide on hiring the right builder here.

FAQ: Common questions about home extensions in Isleworth

Can an extension builder in Isleworth help with planning permission?

Yes, many extension builders in Isleworth can guide you through the planning process. They can help prepare drawings, advise on local requirements, and liaise with your local council to ensure your project meets all necessary regulations.

Can an extension builder in Isleworth handle everything from design to construction?

Many Isleworth extension builders offer full design-and-build services, managing both the architectural planning and construction stages. Ask your builder whether they can provide a complete package or if you’ll need to hire an architect or designer separately.

Will an extension builder in Isleworth help with materials and finishes?

Yes, most extension builders in Isleworth can source materials and offer advice on finishes that suit your design and budget. You can also choose to supply certain materials yourself, just make sure this is agreed upon before work starts.