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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Blose Architectural Services
Rating: 4 out of 5
Extension Builder in Harrow, Greater London
Blose Architectural Services is focused on delivering projects on time, on budget and to the highest quality by using innovative design solutions. We work with householders, contractors and other professionals specialising in finding technical solutions that take projects from the drawing board to completion. We excel in preparing and submitting planning and building regulations applications, helping our clients realise their dream projects.
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Latest review:
Architecture- 24 Jun 2025
Absolutely disaster. He did not complete the job after receiving his full payment and could not get hold of him again. I had to deal with the council and application. Scam!
B.z.brothers ltd
No reviews yet
Extension Builder in Harrow, Greater London
At Bzbrothers, we are committed to transforming spaces and structures with a focus on quality and precision. extensive experience in construction, design, and landscaping to each project, ensuring innovative solutions that are both functional and visually appealing. From the solid foundations required in groundwork and bricklaying to the creative designs in landscaping, we handle each project with meticulous attention to detail. We cater to both residential and commercial clients, offering everything from comprehensive renovations to bespoke installations. Driven by a passion for excellence and a commitment to client satisfaction, we strive to exceed expectations at every turn. We believe in building lasting relationships with our clients, providing reliable service and superior results that make your investment worthwhile. Explore our services and discover how we can make your next project a success. At Bzbrothers, we don’t just build or renovate spaces—we enhance them, ensuring every project is a testament to our dedication and your vision.
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Flamur Hoda
No reviews yet
Extension Builder in Harrow, Greater London
I have more than 15 years experience in residential and commericial construction, House building, extension and refurbishment and the last completed project was house extension, garden refurbishment, painting and decorating. All aspects of building work undertaken with experience of the following: • bricklaying • plastering • painting • roofing • flooring • Tiling • garden fencing • pavement and • House renovation and extension Can create a team of experienced professional working together to get project completed. Hire more workers for bigger projects and other professionals as and when required.
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A A Builder
New on MyBuilder
Extension Builder in Harrow, Greater London
For 7 years, we have helped families grow into their homes instead of moving out. We handle your house extension from the first blueprint to the final coat of paint. You get a dedicated team, fixed timelines, and high-quality work backed by years of local experience. We do the heavy lifting so you get the extra space you need without the stress.
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Delyan Hristozov
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Home refurbishment service, Carpentry,plumbing,electrical
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Latest review:
Carpentry- 22 Sep 2021
Professional, clean and trustworthy lads. Thank you!!
JCH Home improvements & landscaping
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Local builder with 20 years experience in the construction industry. From extensions to bathrooms, windows, doors, patios, kitchens, fully landscaped gardens. Please get in contact for your free no obligation quote
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Latest review:
Decking- 14 Jun 2022
James Hynes of JCH Home Improvements have just refurbished our decking area. We thought it was a straight forward job, just to renew the decking and a tidy up BUT the original wood was so rotted the whole area had to be renewed. Joists, upright timbers etc We are thrilled with what James has done, so much more work than anticipated but the end result is fantastic. Would thoroughly recommend JCH Home Improvements and we will be using the again.
Mushroom Building Services
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are a small building company with over 30 years experience based in Farnham. We offer a full building service from start to finish. We complete all work to the highest standard, no exceptions. We’re fully insured and qualified.
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Latest review:
Conversions - General- 29 Sep 2022
The job - gutting our living room. Tearing down the ceiling, removing all old wallpaper and ripping up the floor in order to insulate and add lighting. While we were doing this, we decided to replace the main steel in the living room (which was oversize and impacted the floor height in the guest room) and do remedial works in the guest room. The steel replacement was not time budgeted, but Oli and Tony didn’t hesitate to quote,To make time for us and bring in the structural engineer. Probably added 3 weeks to their time on site. The trades they brought in (plumbing for heating, electrician for downlighters, structural engineer and plasterers) were all professional, did an excellent job and were all unfailingly polite. It was easy to build a good, positive relationship with them, to the point we felt comfortable giving them the keys to the house so they could work while we went away for two weeks. They sent photos of their progress and showed up and worked as if we were there. I was very impressed by the state of the house when we got back. They watered our plants (I didn’t ask) and they cleaned the hallway so that it was spotless. They did a good job for a fair price, and were always cheerful and open to conversation. They came back to do a few snagging items without being chased (this is a huge thing for me, after having chased many builders to finish bits and pieces). I would definitely use them again.
Escape Home and Garden
No reviews yet
Extension Builder in Harrow, Greater London
Escape is new to my MY Builder, we are a General Builder and Handyman with over 20 years experience. I also love landscape design, anything from a new patio to fencing, brick walls or even a complete new design for your garden, there is no job to small or big. Im a perfectionist who takes pride and responsibilities in his work to a high standard! Im also a qualified FGAS Air conditioning installer. Please have a look at a our pictures and feel free to contact us if you any questions.
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JH Building Works Ltd
No reviews yet
Extension Builder in Harrow, Greater London
JH Building Works Ltd carry out all construction, maintenance, repairs and alterations work. We provide a general building service and undertake work all of scales and types.
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Grand Alliance LTD
No reviews yet
Extension Builder in Harrow, Greater London
Grand Alliance LTD is providing a full spectrum of building works from the foundation to the roof, including commercial buildings.
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Allsop Design and build
No reviews yet
Extension Builder in Harrow, Greater London
New up and coming building company to help with all your needs
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B.S.Contractors
No reviews yet
Extension Builder in Harrow, Greater London
I'm Mechanical Technician by trade but working in construction industry 26 years. I used to do many aspects of building mostly in residential part of construction industry. I succesfuly run loft conversions company between 2003 and 2006.I work myself and I cooperate with other small traders like plumbers and electricians. I mostly do myself structural works, carpentry and joinery, tiling, and roofing. I do complete jobts from structural works to painting and decorating etc.
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BALJINDER Singh
No reviews yet
Extension Builder in Harrow, Greater London
We working in building trade from last 20 years got experienced team We do Extension Loft conversion Bathroom Kitchen Roof Landscaping etc
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EJR Pro Build
Rating: 4.9 out of 5
Extension Builder in Harrow, Greater London
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.
Poul
No reviews yet
Extension Builder in Harrow, Greater London
Loft, extension, carpentry work , houses repairs, kitchen installment , electricity installment and maintenance , conduct designs of interior and exterior according to the customers want.
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E3 Elements Ltd
No reviews yet
Extension Builder in Harrow, Greater London
At E3 Elements, we specialize in all types of insulation work, including loft, cavity wall, and external wall insulation, ensuring your property is energy-efficient and comfortable year-round. Our experienced team delivers high-quality solutions that help you reduce energy bills and improve the overall comfort of your home or business. Alongside our insulation services, we also provide a wide range of general construction services, including renovations, repairs, plumbing, electrical work, and more. Whether it's a small repair or a large-scale project, we are committed to delivering professional, reliable, and affordable results. If you're looking for trusted contractors who put quality first, reach out to E3 Elements for a free consultation today!
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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.