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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KINVEK CONSTRUCTION
Rating: 5 out of 5
Extension Builder in Harrow
We are a family run business, established January 2005, Kevin is a carpenter with over 40 years in the building industry, my son Matthew, who is a plumber, has been working with me for the last 10 years and wife Julie has been in the office since the start We pride ourselves on being friendly polite and trustworthy We do all types of building work, extensions, kitchens, bathrooms, carpentry, plumbing, electrics and decorating, fencing, decking
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Latest review:
Carpentry- 19 Aug 2026
Kevin was very competent supplied all the materials needed and did a thorough good job .I was very pleased and will be hiring him again when he is available
Jackson construction
No reviews yet
Extension Builder in Harrow
I’m a general building company we do complete extensions, kitchens, bathrooms and carpentry, Patios and driveways
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SGW CARPENTRY AND CONSTRUCTION
Rating: 5 out of 5
Extension Builder in Harrow
SGW carpentry and construction provide a great professional service to all customers. Providing all first fix and second fix carpentry as well covering all forms of construction services. A business looking to grow and focused on providing a good standard of work and service to all our customers.
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Cristian Anton Popescu
No reviews yet
Extension Builder in Harrow
professional builder with 25 years of experience in renovations, refurbished, window and door installation, loft conversion, extensions, conservatories, kitchen installation
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Krrashi Construction & Design LTD
No reviews yet
Extension Builder in Harrow
At Krrashi Construction Design, we specialise in premium patios and bespoke landscape maintenance, creating outdoor spaces that are both elegant and built to last. With a strong eye for detail and a commitment to high-quality craftsmanship, we transform gardens into refined, functional environments tailored to each client’s vision. From beautifully designed patios to meticulous ongoing maintenance, we deliver a reliable, professional service that ensures your outdoor space always looks its best.
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Sangfroid Services Ltd
No reviews yet
Extension Builder in Harrow
Brickwork and blockwork Brick cleaning and brick repairs Paving and paving cleaning
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EJR Pro Build
Rating: 4.9 out of 5
Extension Builder in Harrow
Hi I'm Elliott from EJR Pro Build. We are wall & floor tiling contractors/wet room specialists We also offer a range of services from full design and build to general carpentry we are fully qualified Builders & tilers CSCS registered and health & safety trained all work is fully quaranteed & insured
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Latest review:
Extensions- 1 Jun 2022
We are absolutely thrilled with our extension. Elliot and the team completed all elements of the project, which included numerous steels to replace existing supporting walls and the re-fit of our existing kitchen +new kitchen fit out. The work is finished to a very high quality and far exceeded our expectations. Product selections such as doors, windows and tiles were proposed by Elliot and were exactly what we wanted. Elliot and the team were professional and a pleasure to work with and we would highly recommend them.
Virgil And Son Ltd
No reviews yet
Extension Builder in Harrow
We are a Limited Company that has the right builders for each job !
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Platon Interiors LTD
No reviews yet
Extension Builder in Harrow
Specialist interiors refurbishment company and general builder with a vast and extensive experience.
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HA55 Construction ltd
No reviews yet
Extension Builder in Harrow
HA55 Construction ltd has been serving the community for over 8 years and we have experience in everything from New Builds, Extensions to painting and decorating. We are a friendly and reliable team, who are always happy to help and go the extra mile! Trust Quality Strength Understanding of your needs are what is important to us!
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HMR Builders Ltd
Rating: 5 out of 5
Extension Builder in Harrow
I have 19 years experience in the building trade. We can fit new bathrooms, kitchens, build extensions, plumbing, electrical work, staircases, tiling, plastering and most other jobs you may require doing around your house. We have also completed HMO’s, worked with many letting agencies and landlords directly. We are reliable and trustworthy and will work with our customers to make their ideas and dreams a reality. I provide free quotes and am fully insured. I can come and look at a job at a time to suit you including evenings and weekends.
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Latest review:
Bathroom Fitting- 11 Aug 2026
⭐⭐⭐⭐⭐ We’re really pleased with our new bathroom and would definitely recommend Melvin. From the start, he was helpful, hardworking and listened to what we wanted, including the finishes and details we had in mind. The bathroom has been completely transformed and we’re really happy with how it has come together. There were a few finishing touches and snagging points along the way, but Melvin was approachable and came back to address the outstanding items, which we really appreciated. He worked hard throughout the renovation and was happy to discuss things with us and make adjustments where needed. We’re very pleased with the end result and would happily recommend him to anyone looking for a bathroom renovation.
Ows construction ltd
No reviews yet
Extension Builder in Harrow
OWS Construction specialises in a broad range of groundwork and civil engineering services. We handle essential preparatory and foundational tasks for various construction projects, ensuring infrastructure is properly laid out before the main build takes place. Their scope includes: Car parks: Constructing and preparing parking areas. Curbing: Installing curbs and edges for roads or pathways. Drainage: Designing and installing systems for effective water drainage. Utilities: Installing essential services like water, gas, and electricity lines. Concrete: Pouring and setting concrete for foundations, pavements, or other structures. Roads and sewers: Constructing and maintaining road networks and sewer systems. Footings and formwork: Laying the Laying the foundational supports and molds for concrete pours. Steelwork: Installing steel reinforcements for structures. Shuttering: Creating temporary molds for poured concrete. General developer work: Other tasks required by developers to prepare sites for building projects.
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Virtu Projects Limited
No reviews yet
Extension Builder in Harrow
Virtu Projects are a family run business with years of experience in residential, commercial, and industrial construction, we deliver reliable, on-time, and on-budget solutions tailored to your needs. From the ground up, we build with integrity, innovation, and a focus on lasting results.
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N.N2 GENERAL BUILDING
No reviews yet
Extension Builder in Harrow
General building. EXTENSION, LOFT CONVERSION,GARDENS DESIGN,KITCHEN, BATHROOM, ROOFING,PLASTER &RENDERING, DECORATING, DRIVEWAY, PLUMBING, ELECTRICITY...
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Reach Perfection
No reviews yet
Extension Builder in Harrow
Electrical- painting- bricklayer and most construction work apart from plumbing and generally I am a handy man with 7 years work experience in construction
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New Eire construction
No reviews yet
Extension Builder in Harrow
Hi, I’m Sean Walsh, a skilled and reliable builder with years of hands-on experience. I specialise in new builds, extensions, renovations, roofing, carpentry, and general maintenance. I’m committed to quality, attention to detail, and delivering every project on time and on budget. No job is too big or small—I treat every home as if it were my own. Whether you’re planning a home extension, renovation, or maintenance project, I provide professional guidance and craftsmanship you can trust. Let’s make your vision a reality!
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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.