Extension Builders in Castelnau

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.4 (19 reviews)

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Some of our top rated extension builders in Castelnau

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R84L Renov84Less
Rating: 5 out of 5
Extension Builder in Castelnau
We are R84L Renovateforless Ltd, contractor with 100% 5star reviews. After starting over 35 years ago ,we have build reliable team and gained tremendous experience, leaving clients immensely satisfied. Worked hard for our reputation in East Midlands now we transferred to South London. Our team is specialised in interiors,exteriors,kitchen,bathrooms, flooring,roofing,plumbing,electric , extensions and much more. We also work with businesses, transforming office spaces, restaurants and cafe’s. Our designed team will work with you to build your dream home and make it a reality. Nothing is impossible for us. We advise, design and build your dream home or work place.
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Latest review:
Conversation of a ground floor wc in to a shower room with tiling. Always showed up on time and worked all day like a machine. Gives great ideas and trys to save money for client where possible. Have used him again to re do my mums bathroom and again top work and finnish.
House Refurb
Rating: 4.9 out of 5
Extension Builder in Castelnau
We have built our livelihoods on remodelling people’s homes, increasing their size and value. From the simple to the lavish, no matter how big or small, we’ve experienced it all and we can help you every step of the way offering a comprehensive service and take care of all aspects of your project, from initial plans through to full completion. Our skilled workforce of reliable professionals is on duty to offer you quality building work, competitive prices and exceptional customer service.
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Latest review:
Extensions- 24 Feb 2014
Narcis and his team listened carefully to my specifications and completed the job with an excellent finish. Throughout they were courteous and hard working. Highly recommended .
CJ Carpentry
Rating: 5 out of 5
Extension Builder in Castelnau
We are joiners by trade, passionate on what we do over the years. We have combined over 32 years of experience on carpentry/joinery itself. As there is always demand, we started delivering any type of construction work, full house refurbishment, kitchens, bathrooms etc. Always preserving our high quality of work, honesty, professionalism. Fully committed to anything we can come across, always find clients, architects solutions so we can achieve everyone’s dream, expectations.
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Latest review:
Carpentry- 18 May 2022
Very professional and friendly tradesman. Work was carried out perfectly and I couldn't recommend him high enough. Brilliant work ethic and he went the extra mile to carry out the works impeccably. Privellage to work with him.
W.A. Brown Builders LTD
Rating: 5 out of 5
Extension Builder in Castelnau
I have been in the building industry now for over 40 years, I started as a buidlers labourer back in 1983 for my uncle, working on houses and in offices in the maida vale area.
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Latest review:
Carpentry- 20 Jul 2024
Wayne and his team did a great job. Communication and planning was effective from the start, and stuck to the deadline that was set at the beginning of the project. I’d definitely hire again for my upcoming projects.
DME DEVELOPMENTS LTD
Rating: 5 out of 5
Extension Builder in Castelnau
Hi Dan here at DME Developments Ltd, where we specialise in refurbishing domestic properties and have a wealth of experience in both small and large scale projects, work on all types of projects from simple kitchen/bathroom remodels, plumbing/electrics, all the way up to full High-end home refurbishments in and around the SW London area. If you are looking for an exceptional finish on your project, please look no further.
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Latest review:
Carpentry- 29 Jul 2023
Job well done, very professional and great manners. He did a great job within 4 hours. Thank you very much.
Prime contractors
Rating: 5 out of 5
Extension Builder in Castelnau
Prime contractors have been in the construction industry for about 25 years which includes domestic and commercial projects. Some of the domestic projects have been double extensions, loft conversions, house refurbishments and other small internal and external works which also include flat roof and cladding. Commercial projects have been from building double extensions and demolition having worked as a supervisor and manager.
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Latest review:
Conversions - General- 17 Apr 2026
A great experience. Work was completed quickly and to a good standard with an unexpected extra (sorting out the electrics for a light in the crawl space). Most tidy builders I have ever employed. Quick responses and good communication. I'd happily use Prime Contractors again
Inside Out
Rating: 4.9 out of 5
Extension Builder in Castelnau
Inside Out was formed in 2009. We are an established, London based building company operating throughout London and within the M25. We deliver an honest and straight forward service, with quality workmanship at the forefront of everything we do.
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Latest review:
Extensions- 10 Oct 2022
A good team, good building technicians, completed the job according to plan and delivered on time.
Remas Construction
Rating: 5 out of 5
Extension Builder in Castelnau
I been in construction field for over 16 years: (Electric, Plumbing, Plasterboard, Painting, Flooring, Carpentry, GlassWork, Kitchen & Bathroom, Extension and much more..) I believe that quality is the result of careful planning and execution. Daily maintenance solutions.. (Urgent & Same day Service). Best price in London, Guarantee 💯 GENERAL CONTRACTOR'S Commercial & Residential Home inspection
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Latest review:
Ahmad did an exceptionally good job. He painted a large number of walls, filled them, gave me a recommendation as to what paint should be used and left everything clean and tidy every day. Highly recommended.
IDEAL Carpenters LTD
Rating: 5 out of 5
Extension Builder in Castelnau
Hello I am a skilled carpenter, with over 23 years experience working in and around London, I can undertake most all jobs concerning building works around the Home but also have a team of reliable sub trades including “Gas Safe engineers” and qualified electricians, If you need any work done, by some one you can trust and rely on then please don’t hesitate to short list me, for your next project, Regards Agron
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Latest review:
Conversions - General- 28 Jun 2026
We recently had our detached single garage converted into a fully usable room by Agron and his team, and we couldn't be happier with the result. The project involved replacing the garage door with matching brickwork, raising the roof, installing new windows and a door, insulating the garage, plaster boarding and skimming throughout, and rendering and painting the exterior. The work was completed to an exceptionally high standard. Agron and his team were fantastic from start to finish. They were incredibly friendly, professional and hardworking, completing the project quickly without ever compromising on quality. Communication was excellent throughout, they kept us updated on progress and always made sure we were happy with how the project was proceeding. They were also very accommodating and happy to adapt to any requests or changes we made along the way, making the whole process stress free. The attention to detail and pride they took in their work really shows in the finished result.
OL and Edward Limited
Rating: 4 out of 5
Extension Builder in Castelnau
Years in business: since 1996 At OL & Edward Limited, we take pride in delivering creative solutions which are as practical as they are eye-catching – no matter if it’s a home interior makeover or commercial development; from concept through completion each project gets special attention down to even the tiniest details for maximum impact results worth celebrating about! But don't just take our word for it – experience first hand why clients come back again (and again!) by taking advantage of any one of our services today: Full home renovation, bathroom and kitchen installation, flooring, tiling, consultation, design, exterior works and much more
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Latest review:
Restoration & Refurbishment- 17 Feb 2025
Great job on cleaning and refurbing our 2 bed flat. Very professional and responsive. Would hire them again in a heartbeat.
AEE Construction Ltd
Rating: 5 out of 5
Extension Builder in Castelnau
General renovations, electric, plumbing, decoration, painting, kitchen fittings, tiling, flooring, bathrooms, extensions, loft conversions and property maintenance
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Latest review:
Handyman- 27 Jul 2023
Very professional and polite man. Job done neat and professionally. Would highly recommend.
Bare Interiors
Rating: 5 out of 5
Extension Builder in Castelnau
We are a small company of 5 people (with more than 15-20 years of experience each) having 2 vans carrying all the tools needed. We can provide you with any services from kitchen / bathroom fitting , to full house renovations and extension builds.
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Latest review:
Bathroom Fitting- 9 Feb 2019
Alexandros did an exceptional job with our bathroom. As it was our first major renovation we were very anxious about the whole process but Alexandros made everything very easy and smooth from the beginning until the end. Alexandros has a lot of experience and he is full of ideas and good suggestions. The new bathroom looks amazing and we could not have chosen better than Alexandros. Alexandros was very helpful throughout the whole process. I would highly recommend Alexandros to anyone and we will definitely use his services in the future.
J&D
Rating: 5 out of 5
Extension Builder in Castelnau
My name is Jacek i have been working as a builder for 15 years in UK I working with a team and we are good at Extensions Refurbishment Kitchens Bathrooms Rendering Plastering Painting
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Latest review:
Plastering- 24 Nov 2019
In the middle of finishing our kitchen job. His plastering has been excellent. Waiting now for a paint finish. Very punctual, honest and thorough with his job. I am very pleased we hired Jacek and will definitely be hiring him in the future. Thank you Jacek.
W4 Builders
Rating: 5 out of 5
Extension Builder in Castelnau
We do all kind of building services in west London. We do painting, decorating as well as plumbing and electrics. We do bathrooms and house extensions and full property refurbishments.
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Latest review:
Robert Biegala has done laminate flooring, decorating and other tasks in my office in Farringdon. It was pleasure to work with Robert as he is a reliable, responsible and trustworthy person. His communication was consistent and reassuring. Robert is proactive and finds solution to any problems which arise during works. I would highly recommend his services.
Zenstruction
Rating: 5 out of 5
Extension Builder in Castelnau
Established in 2005, we are a trusted building company with extensive experience in all aspects of construction, from new builds to fascia and gutter installations. Known for delivering high-quality projects on time and within budget, we maintain the highest standards of workmanship, safety, and reliability. Our expertise spans a wide range of services, ensuring that each project is completed to exceptional standards, meeting both client expectations and industry regulations.
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Latest review:
Extensions- 3 Sep 2018
Zen has helped transform our home, we’ve drawn a lot of confidence from his considered approach and thorough work ethic. He’s so far addressed the cause of cracks to exterior walls of our property and has provided lasting solutions. We also asked him to plaster our hallway and update the banisters for us, Zen has done a great job of reinforcing the strength of the original features whilst retaining the property’s character. Very good with pets too. Looking forward to the next project.
ALBERTHALL CONSTRUCTION LTD
Rating: 4.7 out of 5
Extension Builder in Castelnau
I am and my team are all highly skilled builders with vast knowledge and skills. We have been in the construction industry for 15 years, specialising in extensions, loft conversions and whole house refurbishments. We are new to the MyBuilder portal, so are short on feedbacks. Therefore we will provide references from previous clients.
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Latest review:
Extensions- 13 Oct 2023
Sagar and Sanjeev are incredible- they are very diligent and really well versed in what they do! They know what they are talking about and are very friendly and incredible to work with. There was no issue that they weren’t able to help me through when it came to a complete renovation, extension and garden landscaping of my house. They are experts in what they do and they’re the only contractors I want to work with for any other works in the future. Would always recommend them. 100/100!

4.4

Top rated Extension Builders

Our Extension Builders in Castelnau, are rated 4.4 out of 5 based on 19 reviews from customers like you.

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

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 Castelnau 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 Castelnau who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Castelnau?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Castelnau 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 Castelnau extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Castelnau home extension project is likely to cost.

Find extension builders in Castelnau with MyBuilder

Hiring the right extension builder in Castelnau 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 Castelnau extension builders. Once your job is live, we’ll share it with home extension builders in Castelnau who can express their interest.

Step 2: Compare different extension builders in Castelnau

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

Step 3: Hire Castelnau extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Castelnau, 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.

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

What to ask a Castelnau extension builder before hiring?

Before hiring an extension builder in Castelnau or extension building company in Castelnau, 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 Castelnau?

An extension builder in Castelnau 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 Castelnau 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 Castelnau?

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 Castelnau 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 Castelnau 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 Castelnau

Can an extension builder in Castelnau help with planning permission?

Yes, many extension builders in Castelnau 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 Castelnau handle everything from design to construction?

Many Castelnau 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 Castelnau help with materials and finishes?

Yes, most extension builders in Castelnau 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.