Extension Builders in Harrow, Greater London

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 Harrow, Greater London

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Smart Build Construction Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Welcome To SMARTBUILD Construction Ltd, SMARTBUILD Construction Ltd is an established family run business operating from Rickmansworth servicing Watford, North London, Hertfordshire and surrounding region. At SMARTBUILD we have gained an enviable reputation based on offering quality of products, installation, customer service and value for money.
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Latest review:
Steve is thoroughly recommended. Turned up on time, work was done to a good standard. Would definitely use again.
Danut
No reviews yet
Extension Builder in Harrow, Greater London
Brick work , roofing, tiles roof flat roof, patio
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Robi paiting decorator
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Extension Builder in Harrow, Greater London
We perform work reliably and to a high standard
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Emperor Contractors Limited
No reviews yet
Extension Builder in Harrow, Greater London
This is a construction company with many connections within the industry. Quality and longevity describes our state of works. We have a portfolio of many projects which all of them have been successful.
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FLV PROPERTY LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
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!
Samy
No reviews yet
Extension Builder in Harrow, Greater London
I’m on the busines more than 10 years please letmy help we’d your garden Driwey fence and autbuilding For more information please call mail or text
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Gotbath UK Ltd
Rating: 4.7 out of 5
Extension Builder in Harrow, Greater London
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.
Toma Construction Limited
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
I have over thirty years experience undertaken all type of building works including extensions, loft conversions, refurbishments and conversions. No job to big or to small.
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Latest review:
Groundwork & Foundations- 18 Dec 2020
Had three quotes for a base for a garden shed, Toma was the cheapest by far. We arranged a day for the work to be done, bit apprehensive because I never knew anything about the company. Mr Toma and two others turned up, what lovely people they were, especially Mr Toma, the job was highly professional, everything was tidied up. Would I use them again.........100%. I would highly recommend them.
FPA PROPERTY SERVICES LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Here at FPA property Services LTD we pride ourselves on the prefect job, our company has grown in size due to our hard work & our outstanding standard of finish. we offer a bespoken services for any size job from the design stage to the complete build. We are proud members of the FEDERATION OF MASTER BUILDER & TRUSTMARK. The only Government Endorsed Quality Scheme. Our services cover commercial & domestic projects. We can take on any size job from a rental touch up to a complete new build.
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Latest review:
Extensions- 15 Oct 2020
Frankie is an excellent builder, he is professional, polite and courteous and he has completed our extension to a very high standard. He is incredibly hardworking and has finished the extension at pace, but with care and attention. I have no hesitation to recommend Frankie and indeed have already done so, to friends and family.
Franzosi Brickwork
No reviews yet
Extension Builder in Harrow, Greater London
Newly qualified bricklayer after 3 year apprenticeship looking for small jobs.
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CHL IMPROVEMENTS LTD
No reviews yet
Extension Builder in Harrow, Greater London
North London based 10 years of experience
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Phoenix Roof Developments
No reviews yet
Extension Builder in Harrow, Greater London
Phoenix Roofing & Developments provides expert roofing and development services to commercial and domestic clients across Buckinghamshire and Oxfordshire. From inspections and repairs to complete roof replacements, we deliver quality craftsmanship and use the finest materials to safeguard your home. For cost-effective roofing services, look no further than Phoenix Roofing & Developments. Our friendly and qualified staff use only high-quality materials for all projects, so you can be sure that you will get a service that is second to none. We are new to this platform but have many verified reviews and are happy to share them with you. As a company, we don't take up-front fees and take images throughout the working process to ensure transparency throughout the service. Once the job is completed and you are happy, we expect payment via bank transfer
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Professional Electrician Ltd
No reviews yet
Extension Builder in Harrow, Greater London
Welcome to All in Renovation LTD, your all-in-one renovation experts! We specialise in giving buildings a fresh look, inside and out, including electrical work. From remodeling interiors to upgrading exteriors, count on us to handle every aspect of your project. Let's bring your vision to life!" We pride ourselves on giving all of our customers 100% outstanding service, making our customers return and recommend. We understand our customers have different individual needs and requirements, therefore we work with them on a personal level to ensure you will be satisfied from start to finish. No job is too big or too small, all enquires welcome, please just ask and we will do our best to accommodate.
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london construction company
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Established in 1994 , Family run business . Friendly reliable service , Extensions / lofts and landscape specialist
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Latest review:
Extensions- 15 Feb 2026
Incredibly professional, super fast response, great quality of work, sound and thorough advice, available and patient at all times - Terry did a great job putting together my garden office installation at short notice despite inclement weather. I can vouch sincerely for his work and will definitely recommend him
DBMP LTD
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Our focus is to provide customers with expertise, quality workmanship, and a high level of communication throughout the process. We pride ourselves to offer a high level of customer satisfaction, this has been our main driving force over the years. We are fully insured.
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Latest review:
Insulation- 28 Feb 2023
A Great British company who I will call first for all future work. I have multiple properties and seen many traders. Workmen never give compliments to others but two of my regulars were there and both told me his work/team were very good. DBMP treat the work like it is their own property. Good quality work, neat, thoughtful of other workmen/tenants, took all the rubbish away. No mean feat as he replaced skirting & floorboards, installed rock wool and rubber mats, re-fitted carpets, painted woodwork and moved furniture in & out; all while I had tenants in the house. This site is a gamble but I highly recommend this team.
Cocis Construction Group
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Cocis Construction Group LTD is a family-run construction company with over 25 years of hands-on experience in the trades. We specialise in home renovations, extensions, bathroom and kitchen refurbishments, and property development across London. As a young, ambitious company, we combine traditional craftsmanship with fresh ideas and modern techniques to deliver projects efficiently and to the highest standards. Our team takes pride in attention to detail, clear communication, and building lasting relationships with homeowners, landlords, and property investors alike. At CCG, we don’t just build structures—we bring visions to life, turning ideas into beautifully finished spaces. Contact us today for a free quote and see how our expertise and dedication can make your next project a success.
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Latest review:
Cocis Construction Group done the full interior painting of our 5 bedroom house and we are really happy with the result. The team was polite and worked very hard every day. They kept things clean and finished everything on time like they said they would. The paint finish looks great and the whole house feels fresh again. Would definitely recommend them if you need painting done.

3.9

Top rated Extension Builders

Our Extension Builders in Harrow, Greater London, 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 Harrow, Greater London?

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 Harrow, Greater London 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 Harrow, Greater London who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Harrow, Greater London?

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

Find extension builders in Harrow, Greater London with MyBuilder

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

Step 2: Compare different extension builders in Harrow, Greater London

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

Step 3: Hire Harrow, Greater London extension builders with confidence

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

Harrow, Greater London extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Harrow, Greater London extension builder before hiring?

Before hiring an extension builder in Harrow, Greater London or extension building company in Harrow, Greater London, 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 Harrow, Greater London?

An extension builder in Harrow, Greater London 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 Harrow, Greater London 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 Harrow, Greater London?

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 Harrow, Greater London 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 Harrow, Greater London 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 Harrow, Greater London

Can an extension builder in Harrow, Greater London help with planning permission?

Yes, many extension builders in Harrow, Greater London 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 Harrow, Greater London handle everything from design to construction?

Many Harrow, Greater London 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 Harrow, Greater London help with materials and finishes?

Yes, most extension builders in Harrow, Greater London 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.