Extension Builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.8 (18 reviews)

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Some of our top rated extension builders in Harrow

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R4ebb ltd
No reviews yet
Extension Builder in Harrow
I worked as a builder for 20 years loft ,extension,tiles ,bricks,painting,plumbing,kitchen etc all type of building work I have my team long experience thank you
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KLS Group Ltd
No reviews yet
Extension Builder in Harrow
New builds, extensions, loft conversions, kitchens, bathrooms, roofing, windows, driveways, steelwork, gate automation, general repairs.
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erion sefa
No reviews yet
Extension Builder in Harrow
I run a professional building company delivering high-quality construction and brickwork services. With a strong focus on reliability, craftsmanship, and customer satisfaction, I manage projects from start to finish, ensuring every job is completed to a high standard, on time, and within budget.
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Garnet Construction Ltd
Rating: 4 out of 5
Extension Builder in Harrow
Garnet Construction has over 10 years' experience in the industry and specialise in loft conversions, all types of extensions and complete renovations. Priority is given to the design and construction of all our projects with a unique obsession to strive for perfection.
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Latest review:
Extensions- 18 Sep 2019
To start off with the job went reasonably well - we were happy with the workers and the progress. but when we neared completion the work slowed up we waited 3 months for a response from Jordan. we had an issue where his plasterer hid the plumbing access in the wall. - This cost us £500 to sort and re-decorate so we came to an agreement that this was fine and at the time i presumed that Jordan was going to sort out the building control. so we then chased and chased but obviously since he had his money he wasn't interested he answered the phone and hung up. so we called building control and there are 2 small bits to fix which are all due to his work not being up to scratch. obviously i will be paying out for this - so please be careful when using him and dont pay him until you have all of the documents as he will not resolve any issues after being paid. i have had 2 previous building projects and this was by far the worst experience going. avoid dont use him thanks
A J Morris Plastering And Construction
Rating: 3.5 out of 5
Extension Builder in Harrow
A J Morris Plastering And Construction is a company that specialise in all aspects of Construction to small room refurbishments to extensive structual work to landscaping and creating lovely spaces outside. We have over 15 years of experience in the construction industry so no job is to small or to big for the company and the jobs are always completed to all regulations and also to the highest standard. Customer satisfaction is our number one goal.
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Latest review:
Plastering- 15 Jan 2025
Removing my review due to change of opinion.
B darsi steelfixer ltd
No reviews yet
Extension Builder in Harrow
Hey to everyone! Bdarsi construction ltd We can offer all the costumer a very good service in demolition our staff it’s very professional with many years . If anyone have any questions plz do not hesitate to contact us !
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Winch Brickwork
No reviews yet
Extension Builder in Harrow
Experienced Bricklayer with nvq level 3 gold cscs card. New/refurbished Brickwork/pointing. Painting&decorating Driveways, patios,brick paving Snagging/making good external
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HD Developments (London) Ltd
Rating: 5 out of 5
Extension Builder in Harrow
HD Developments Ltd. For any building work down to even just maintenance, we cover every aspect of the building trade. A lot more information available through contact as we are new to my builder. Thank you.
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Latest review:
Very professional. Job completed in good amount of time. Communicated well with us throughout. Left the house/garden as they found it. Could not fault them and their work. Will definitely be using them for more work in the future! Thank you!
Bshc construction ltd
No reviews yet
Extension Builder in Harrow
BSHC construction is a Luton based company. Our services offered include all building work, brick work, roofing, extensions, loft conversion, tiling, plumbing and heating, flooring. We cover Luton, Bedfordshire and surrounding areas and willing to travel 50 miles. We have 15 years experience is construction industry.
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Bathroom & kitchen
Rating: 4.8 out of 5
Extension Builder in Harrow
Fix building service .The company specialises in maintenance,bathroom & kitchen plumbing and heating gas and electric all qualification. Our aim is to provide customers with an honest, reliable and professional service.
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Latest review:
Kitchen Fitting- 14 Mar 2026
Arthur was really good and install was done super quick in one hour.
Complex building and landscaping
No reviews yet
Extension Builder in Harrow
We are a skilled 3-man building and landscaping team with over 15 years of hands-on experience delivering high-quality construction and renovation projects. Our work spans a wide range of services, including complex landscaping, driveways, bricklaying, kitchens, bathrooms, extensions, and bespoke carpentry. We operate as a tightly coordinated unit, supporting each other across all aspects of the job to ensure efficiency, precision, and a seamless workflow. Our commitment to professional standards and attention to detail ensures every project is completed to the highest quality. Whether it’s a full home extension or detailed landscaping work, we take pride in our craftsmanship and our ability to bring our clients’ visions to life.
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modena builders ltd
New on MyBuilder
Extension Builder in Harrow
Modena Builders is a trusted construction company based in Buckinghamshire, proudly serving Buckinghamshire and the surrounding areas. We provide professional building services at prices lower than the market, without compromising on quality or workmanship. Our experienced team has multiple trade skills, allowing us to complete almost every aspect of construction in-house. Whether you need a house extension, new build, full renovation, loft conversion, garage conversion, bathroom installation, kitchen fitting, plumbing, electrical work, bricklaying, plastering, rendering, roofing, carpentry, tiling, flooring, painting and decorating, landscaping, driveways, patios, fencing, structural alterations, RSJ installation or general property maintenance, we've got you covered. From small repairs to complete property transformations, Modena Builders delivers reliable, high-quality workmanship, honest pricing and a professional service from start to finish. One company. Every trade. Lower prices than the market.
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JPD PILING & GROUNDWORK LTD
Rating: 4.8 out of 5
Extension Builder in Harrow
We are a specialist piling & groundwork company / new build & extensions builder & include Lanscaping with 25 years experience.
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Latest review:
Groundwork & Foundations- 20 Sep 2018
JPD boys came to rescue us when we were almost stuck with our RC foundation on our project, we got a very competitive quote from them and the job was done to a very high standard. Not only did they helped with that, they also gave us a quote for the block work, again this was done without snagging. We will definitely use them over again and recommend them to anyone anytime.
Art Building and Interiors Ltd
No reviews yet
Extension Builder in Harrow
Hi! My name is Daniel, and I'm a multi-trade builder with a passion for all construction work and over 16 years of experience.
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Andy
No reviews yet
Extension Builder in Harrow
I have worked for 12 years as a builder. I have a team that can do anything: first fix, second fix, etc.
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BBM CONTRACTS LTD
Rating: 5 out of 5
Extension Builder in Harrow
BBM Contracts Limited. Professional Building contractors successfully offering our clients taylor made building solutions carrying out and successfully managing domestic/commercial building works from extension, refurbishment, alterations and conservation works. Including traditional brickwork and rendering with lime mixed mortars. Construction of Oak frame buildings and barn conservations. Including but not limited electrical, HVAC, carpentry, ground works, painting and decorating.
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Latest review:
Groundwork & Foundations- 22 May 2020
Nick was very responsive throughout the project, knowledgable and able to advise on best practices. Despite the current challenges working with social distancing requirements, he completed the job to a very high standard. Would certainly recommend Nick and his team.

3.8

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 3.8 out of 5 based on 18 reviews from customers like you.

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

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 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 who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Harrow?

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

Find extension builders in Harrow with MyBuilder

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

Step 2: Compare different extension builders in Harrow

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

Step 3: Hire Harrow extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Harrow, 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 extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Harrow extension builder before hiring?

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

An extension builder in Harrow 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 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?

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 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 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

Can an extension builder in Harrow help with planning permission?

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

Many Harrow 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 help with materials and finishes?

Yes, most extension builders in Harrow 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.