Extension Builders in Castelnau

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.2 (20 reviews)

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Some of our top rated extension builders in Castelnau

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Kingston Surrey Construction Ltd
Rating: 5 out of 5
Extension Builder in Castelnau
We are a construction company with over 25 years experience. We Have worked on major projects including extensions, loft conversion and refurbishments. Including smaller projects, new bathroom and kitchens.
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Latest review:
Restoration & Refurbishment- 21 Apr 2024
Got my cloakroom re-done. They r friendly, professional, attention to detail, with clearly tens of years’ experiences. Reasonable rate as well.
Brick House Builders LTD
Rating: 5 out of 5
Extension Builder in Castelnau
Hi, I’m Jatinder. I’ve been working in the building trade for 15 years now. I’m qualified as an electrician and a gas safe register. I specialise in building new houses, loft conversions, extensions, and house renovations.
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Latest review:
They were very professional and quote provided was very efficient and cost effective. The job was finished on time. High recommend.
Boundary builders
No reviews yet
Extension Builder in Castelnau
Family run company specializing in making more space extensions, loft conversions, out buildings,new builds. we can take the stress out of building for you from the start to finish with setting out architecture drawings building control structure build and interior ..
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Surrey Build and Maintain
Rating: 5 out of 5
Extension Builder in Castelnau
Surrey Build is a newly formed business that focuses its efforts on residential dwellings. Wheather you are looking to extend upwards or outwards, or refurb we, at Surrey Build have it covered. We pride ourselves on maximising clients budgets to their full potential whilst providing an uncompromising service.
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Latest review:
Extensions- 1 Jun 2020
We choose Surrey Build & Maintain because we felt like Dan and the team really listened to our vision for the extension and shared the desire to produce something that would be an amazing improvement to our house. As with any build, there were many hurdles to overcome. Dan and the team were always there on hand to deal with challenges and overcome them in a professional and experienced fashion. We really felt that Dan was on our side and was able to find numerous ways to improve the project as well as saving money by assisting to redesign the structural plans as they were unnecessarily overzealous. The team was punctual and hard-working, often working on weekends to increase the rate of construction. We stayed at the house during the build and Dan made every effort to make the impact on us as minimal as possible, laying dust sheets, cleaning up each day and keeping a temporary kitchen available to us during the project. We took advice on key features like doors and windows from Dan during the build and absolutely loved his design input. The end result is fantastic and we barely use any other room in the house! Since Dan began the kitchen extension we have also employed Surrey Build to overhaul our bathroom as well. Highly recommended!
new vision construction(uk) ltd
Rating: 5 out of 5
Extension Builder in Castelnau
New Vision Construction (UK) Ltd is committed to provide the highest quality professional construction services. This commitment can only be maintained through the efforts of its people. We provide quality construction services to our clients. The pride we have in our work enables our clients to enjoy the construction process with confidence.The craftsmanship quality we produce is visible in all our finished projects regardless of the projects size.
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Latest review:
Bathroom Fitting- 17 Jul 2020
Very professional & skilled builder. Aswell as a full bathroom refurbishment he took extra time on the small details to really make it a special end result. Me & my family are very pleased with Ranjits work. A very helpful and knowledgable man. Thanks Ranjit for a great bathroom for me & my family to enjoy.
REVOSPACE CONSULTING LTD
Rating: 5 out of 5
Extension Builder in Castelnau
Revospace – Building Better Spaces Revospace delivers high-quality refurbishments and property improvements across London and surrounding areas. With years of hands-on experience in residential projects, we understand how to combine strong workmanship with structured project management to deliver results on time and within budget. We have worked on full refurbishments, kitchens, bathrooms, flooring, carpentry, decorating and general building works. Our background in site management means we don’t just complete jobs — we plan, coordinate and manage them properly from start to finish. Based in London, we operate across Greater London and Essex, and are happy to travel for the right project. Our strengths include attention to detail, reliable scheduling, transparent pricing and clear communication throughout every stage of the job. We respect your home, keep sites clean and ensure work is completed to a high standard. At Revospace, we believe in doing things once and doing them properly — no shortcuts, no hidden surprises. Quality work. Clear communication. Professional delivery.
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Latest review:
I recently had a full kitchen installation carried out and I’m really pleased with the results. From start to finish, the work was completed to a high standard and everything was done with great attention to detail. The installer was professional, punctual, and easy to communicate with throughout the project. Any issues or questions I had were dealt with quickly and clearly, which gave me confidence that the job was in good hands. The workmanship is excellent – everything is level, neatly finished, and exactly as discussed. They also kept the workspace tidy each day and made sure everything was cleaned up properly once the job was complete. The kitchen looks fantastic and has completely transformed the space. I would happily recommend them to anyone looking for a reliable and skilled kitchen installer, and I would definitely use them again for future work.
JKD building service
Rating: 5 out of 5
Extension Builder in Castelnau
14 years experience with House extension, loft conversion, kichen, bathroom and many more.
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Latest review:
Bathroom Fitting- 22 Nov 2019
Perfect job and attention to detail. Wall & floor tiles look perfect. Very tidy, clean and hard working builder. Nothing seemed to be a problem. I also painted the wall. Love the bathroom now. Thank you !
H4construction ltd
No reviews yet
Extension Builder in Castelnau
Having been in service for many years, I've gained a breadth of knowledge and make a point to continually improve our skills as acompany, so that you have the confidence to employ our services and feel satisfied with that choice. We carry out all types of works may it be decorating or a full refurbishment, We also specialise in extensions of the home such as loft extensions kitchen extensions and also more recently we have designed and installed many bespoke garden rooms
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Uk property solutions (ups) ltd
No reviews yet
Extension Builder in Castelnau
Hello. I have been in the building industry for over thirty years. I’m a competent professional and cover all aspects of the industry. Please don’t hesitate to contact me for professional advise quotations ect.
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Su Su Construction Limited
Rating: 5 out of 5
Extension Builder in Castelnau
Welcome to Susu Construction: Your Premier London Construction Partner Are you searching for a London construction company that stands out for its excellence, commitment, and innovation? Look no further than Susu Construction, your go-to choice for top-notch construction solutions in the bustling capital of London.
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Latest review:
Groundwork & Foundations- 2 Dec 2022
We are very happy and glad to have found Su Su Construction. It is great to work with such an open minded contractor who is very experienced and diligent. To us architects it is really important to be able to explore alternative means of construction in order to create long lasting, beautiful and healthy environments and with SuSu we are on the right track. Highly recommend.
KG DESIGN & BUILD LTD
Rating: 5 out of 5
Extension Builder in Castelnau
Hi I`m Kleida .I worked in Building industry for a while now and I have built a quite a knowledge on extensions loft conversion and refurbishment . I recently decided to start working for myself .I also have a very good working team with various knowledge on various stages of projects .
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Latest review:
Conversions - General- 8 Oct 2025
Gaz and his team were professional and hard working, and clear about what would happen when. The job is now finished to a good standard, and on time.
Urban Construction Management Limited
No reviews yet
Extension Builder in Castelnau
We have been in business since 2015, and working with a number of leading contractors within the construction industry in the country. We have carried out works from new builds to refurbishments, and specialise in loft conversions and extensions, garden rooms, kitchens and bathrooms, and structural alterations. We have all the relevant insurance - employment liability, public liability and professional indemnity cover. We are certified by Construction Line, CHAS, Safe Contractor and BMTrada (Fire Door Installer).
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Mann Renovations & Electrical Services
Rating: 5 out of 5
Extension Builder in Castelnau
We are a family run safe and reliable firm with over 25 years experience in all aspects of renovation building & electrical work of all types. We also guarantee all our work, look forward to hearing you. Thank you Frank Mann
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Latest review:
Electrical- 24 Jun 2019
Quietly and professionally got on with the job with expert advice along the way. Very happy.
Loftxtnd Limited
Rating: 5 out of 5
Extension Builder in Castelnau
Hello! We are offering full range off work:full refurbishment,loft conversion,house extensions,driveway!
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Latest review:
The project lasted from July 2023 to Feb 2024 and comprised of: 1. Single story rear extension with new kitchen and underfloor heating 2. 75m2 patio 3. Internal reconfiguration including removal / installation of walls, new flooring, plumbing (including new boiler), new door frames, doors and skirting, redecoration, carpentry for cupboards 4. Ventilation of existing roof The team are both friendly and professional with Alin always on hand to manage any questions / situations as they arise. The work is clearly costed and every two weeks a valuation takes place to ensure transparency of work undertaken both in original scope and any extras. The quality of the build was excellent, something the building inspector commented on. Alin was recommended to me based on past work, and I in turn would highly recommend him.
MS builder
Rating: 5 out of 5
Extension Builder in Castelnau
My company working in construction field from last 6 years. With the help of many years experience we finish our work with good quality on time and provide customer satisfaction.
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Latest review:
MS builder done our house refurbished and renovated, they provide very qualitative work. Their team members are very helpful.
H&J Properties 02 Ltd
Rating: 5 out of 5
Extension Builder in Castelnau
H&J Properties is your friendly, reliable small team with over 10 years of experience in the building industry. We design, plan, build, and project manage, so you can rely on us for a full round of service. From floor and wall tiling to full kitchen and bathroom installations, we’ve got your home covered. We handle plastering, painting, drylining, insulation, and more with precision and pride. Need a loft, rear or basement extension, a new roof, or concrete work? No problem. Whether it’s bricklaying, basement waterproofing, or installing windows and doors, we bring craftsmanship and care to every job. Big or small, we build it right. Please message us directly for more project images.
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Latest review:
We have contracted H&J Properties for our house refurbishment in London. I was impressed with the team's professionalism and project management from start to finish. We had no plans or planning approved, so we wanted a design and build company who will be able to look after the project from start to finish. They did just that. Working with the architects and the planning application before starting the project planning. As always, there are, of course, unforeseen issues arising with the old houses in london but I could't be happier with the communication received from the team. Thanks for the great job.

4.2

Top rated Extension Builders

Our Extension Builders in Castelnau, are rated 4.2 out of 5 based on 20 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.