Extension Builders in Harefield

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (15 reviews)

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Some of our top rated extension builders in Harefield

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Triple-S Construction Ltd
Rating: 5 out of 5
Extension Builder in Harefield
When choosing a building team, you want to be confident your project is in safe hands. You want certainty the job will be done to a high standard and won’t drag on. You want clarity about the cost. You want to feel your investment was worth it. We’ve earned a reputation amongst our clients and within the construction industry, not only for the quality of our work, but also our integrity in business. First and foremost, we treat our clients fairly and always operate with honesty and transparency: it’s one of the reasons so many of them use us again and again. “We entrusted the complete renovation of our family home to Triple S and it was the best decision we could have made. They take genuine pride in their work and, most importantly, they stand by their word.”
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Latest review:
Extensions- 6 Sep 2017
Very professional and did a great job. can't be any happier with the final result. I'll definitely go back to them for any other building jobs in the future.
J M HARJI CONSTRUCTION LIMITED
No reviews yet
Extension Builder in Harefield
J M Harji Construction Ltd is a reliable and experienced building company specialising in high-quality residential and commercial construction. We handle everything from extensions, refurbishments, and renovations to new builds and structural work. Our skilled team takes pride in delivering excellent workmanship, clear communication, and projects completed on time and within budget. Whether you’re improving your home or starting a new project, you can count on us for professional service and outstanding results.
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RS building
Rating: 5 out of 5
Extension Builder in Harefield
We’re a highly professional team with over 20 years’ experience in extensions, loft conversions, high-end renovations, new builds, and property conversions. We deliver top-quality work on time and within budget. Our rates are among the most competitive in the UK at £180 per day per man + 10% OHP. With all specialist trades under one umbrella, we can handle projects of any size smoothly—from £20k up to £2m. Happy to discuss your project further
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Latest review:
RS Building successfully delivered two full back-to-brick refurbishments and a new-build development for us in Greenwich, including demolition and construction of four new dwellings. Their level of workmanship is exceptional, and their attention to detail is second to none. As experienced property developers, we’ve worked with many contractors—but RS Building stand out for their reliability, quality, and professionalism. We have since recommended them to several colleagues, all of whom have been equally impressed. Our only regret is not finding them sooner. We look forward to working with them again on future projects.
Stoneridge Construction & Interiors Ltd
Rating: 5 out of 5
Extension Builder in Harefield
Stoneridge Construction & Interiors Ltd are an experienced team of tradesmen offering an outstanding quality of work for a reasonable price. We pride ourselves on being friendly & reliable builders who’s main aim is to exceed the customers expectations. We undertake all aspects of building, renovation & maintenance work. If you are looking for an efficient, professional & cost effective building team for your project then please get in contact with us today.
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Latest review:
Plastering- 21 Jan 2021
Professional team and job very well done
Orbital construction limited
Rating: 1 out of 5
Extension Builder in Harefield
We a family run business and have been in the building business for 38 years . Our ethos is treat every project as it is our own and have pride in completing a scheme that satisfies all involved.
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Latest review:
Groundwork & Foundations- 10 Feb 2026
I Have arranged a site visit with ORBITAL CONSTRUCTION LIMITED they didn’t turn up no even answer the phone call .
George
Rating: 5 out of 5
Extension Builder in Harefield
Mini digger and driver hire and I’m specialist in bricklaying , choose me if you need something to dig cheap Thanks
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Latest review:
Groundwork & Foundations- 7 Jun 2023
Did has work quickly
LUXE CREATE AND BUILD LTD
Rating: 3 out of 5
Extension Builder in Harefield
Highly experienced builder with 10 years + in the construction industry, undertaking loft conversions, extensions and renovations, paving, fencing. Contact me to discuss your requirements.
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Latest review:
Bricklaying- 26 Nov 2020
Turned up to look at the job and then didn’t bother to quote for it or to answer calls. Completely wasted my time
MLCC
Rating: 5 out of 5
Extension Builder in Harefield
We offer quality works at competitive prices. We are a small team of professional builders with over 12 years of construction experience. Whether you are looking for painting a room or bathroom refurbishment or building a new extension - we can take care of it all. Please contact us today for a free no-obligation quote.
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Latest review:
Painting & Decorating- 27 Apr 2018
Claudiu and his team did an excellent job renovating our 2 bed flat in Bushey. He did a great job on the laminate flooring in particular. Installed coving, skirting, painted walls/doors/radiators, installed new light fixtures, and assembled furniture. Will definitely work with him again. In fact, I hired him back to do our bathroom next week!
Gotbath UK Ltd
Rating: 4.7 out of 5
Extension Builder in Harefield
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.
ALBERTHALL CONSTRUCTION LTD
Rating: 4.7 out of 5
Extension Builder in Harefield
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!
MMC Mesi’s Maintenance LTD
Rating: 5 out of 5
Extension Builder in Harefield
Renovating houses extensions quarters decorating bathrooms instalment kitchen instalment
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Latest review:
Bathroom Fitting- 5 Apr 2022
A good experience, a quality job at a competitive price
REAL HOUSE
Rating: 5 out of 5
Extension Builder in Harefield
The REAL HOUSE construction company was founded in 1997 as a family business. Its founder was Krzysztof Waligora. It has also been active in England since 2015. For over 30 years, we have been guaranteeing our clients high quality of work, in accordance with construction technology and knowledge, professional service and technical consulting in the field of our work. Our goal is to achieve the satisfaction of our customers with the final result of our work.
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Latest review:
Extensions- 2 Oct 2019
Kris is a very friendly, reliable and knowledgeable professional and completed our rear extension to perfection. Competitive prices and finished to a high standard. We would highly reccomend him to everyone!
H S CONSTRUCTION LONDON LTD
Rating: 5 out of 5
Extension Builder in Harefield
HS construction is a reliable business based in Berkshire/West London covering all aspects of building work. Established since 2009, HSC has worked with many homeowners and architects to deliver high-quality structures across London and home counties . HSC are a registered and fully insured business ready to take on projects no matter how big or small . We offer a free no obligation quote and a site visit prior to quotation as well as having many links with experienced architects .
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Latest review:
I have been using HS Construction London for many years ranging from a full house refurbishment to smaller unexpected issues. I have always found them to be reliable and genuine. There are never any hidden surprises in the end. Sunny listens to his customers and also gives decent advice where needed. Their work is of quality and has a long life. I particularly impressed with how they complete the job in a timely manner. All the materials that have been used are of great quality; and it shows. In addition, HSC has many contacts such as architects, suppliers etc which has made my life so much easier. Reasonably priced and with great knowledge, i would certainly use them again.
Plaza
Rating: 5 out of 5
Extension Builder in Harefield
With over 10 years of experience in the London construction market, our company provides a wide range of professional building and renovation services. We specialise primarily in all types of tiling work — whether for bathrooms, kitchens, gardens, or outdoor areas. In addition, we handle smaller tasks such as painting, repairs, and installations, as well as full-scale plumbing, electrical work, and complete refurbishments. We take great pride in our reliability, punctuality, and the high quality of our workmanship. Every project is carried out with exceptional attention to detail, ensuring cleanliness, precision, and a solid guarantee on all completed work. I’m are always happy to offer expert advice and support throughout the renovation process, including assistance with sourcing and delivering materials needed for the job. My works covers a wide range of projects — from full bathroom renovations to flooring, kitchen upgrades, exterior work, and bricklaying. Upon request, I can also provide client recommendations from previous projects to confirm the quality of service
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Latest review:
Kitchen Fitting- 19 Aug 2026
David did an excellent job of installing my kitchen. He went above and beyond to make sure the installation deadline I had was met, and was very helpful and professional. I would highly recommend him.
Peter The Builder
Rating: 5 out of 5
Extension Builder in Harefield
Hello. My name is Peter. I am a builder based in Slough. I used to run my own business back in Poland for 10 years. I do all sorts of work like painting, decorating, tiling, flooring, kitchens, bathrooms, plastering, bricklaying, driveways, gardening, fencing, paving and patio slabs , turfing . I am respectful and keen to get the job done. Thank you so much for your time , Kind regards.
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Latest review:
Fencing- 9 Jun 2026
Recommended - competitive price and completed as agreed.
Hayco Construction
No reviews yet
Extension Builder in Harefield
HAYCO CONSTRUCTION • Established 24years • Northwood, Middlesex • Extensions • Conversions & refurbishments • Garden rooms & offices • Paving & fencing • Electrical & plumbing • £5 Insurance Liability • No job to small
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3.9

Top rated Extension Builders

Our Extension Builders in Harefield, are rated 3.9 out of 5 based on 15 reviews from customers like you.

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

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

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

What are the hourly rates of extension builders in Harefield?

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

Find extension builders in Harefield with MyBuilder

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

Step 2: Compare different extension builders in Harefield

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

Step 3: Hire Harefield extension builders with confidence

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

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

What to ask a Harefield extension builder before hiring?

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

An extension builder in Harefield 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 Harefield 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 Harefield?

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 Harefield 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 Harefield 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 Harefield

Can an extension builder in Harefield help with planning permission?

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

Many Harefield 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 Harefield help with materials and finishes?

Yes, most extension builders in Harefield 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.