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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Gurwindersingh4ltd
Rating: 4 out of 5
Extension Builder in Harrow
Hi my name is gurwinder singh I am skilled in plumbing, skimming , roofing , tilling , bathroom fitting , loft, garage conversions . I do jobs at affordable rates. Thanks
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Latest review:
Tiling- 21 Jan 2023
I highly recommend this builder and the team behind it. They have been very professional and efficient in their work, and the results have been outstanding. They have been very accommodating and communicative throughout the entire process, and I have found them to be extremely knowledgeable and helpful. The quality of the work is top-notch and I would not hesitate to recommend them to anyone looking to have a building project completed.
KW Electrical Services
Rating: 5 out of 5
Extension Builder in Harrow
Hi my name is Kevin and I have been an electrician since 2002. I run a small electrical business called KW Electrical. I am a Which Trusted Trader, Hertfordshire County Council Approved, Part P Registered, over 150 reviews on Checkatrade and all round nice guy. I look forward to quoting competitively on your job.
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Latest review:
Kevin did the electrical work in my extension. He fitted new plug sockets, aerial socket and sky socket, also LED ceiling lights and outdoor PIR light. Kevin was very professional, polite and reliable. He worked efficiently and was tidy. He was also very helpful and explained things clearly to me. I have recommended Kevin to a friend and I will be using him again next year.
QC Gabriel
No reviews yet
Extension Builder in Harrow
Full Refurbush,Roof,Loft Convertion,Electric,Plumber,Brick work,Garden...etc
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Construction
Rating: 1 out of 5
Extension Builder in Harrow
We do all construction work Skim ,paint ,wood floor , floor tiles ,krainder Bathroom ,new extension and garage Brick nd block work
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Latest review:
Bricklaying- 11 Mar 2023
The builder came to build a single skim brick wall to the side entrance of my house -: around 120 bricks. He agreed to £300 for labour including inserting a door. Upon arrival, of which he came on foot, he had no tools, no bucket, no drill, no ladder. He had to borrow all of my husbands equipment and sent my husband out for extra materials on two occassions. The lintel he asked us to order was the wrong size, we ordered one that was far too big and wasted more money due to him measuring up the job wrong - again a waste of money. Then, we had to drive him to toolstation to buy a brick cutting tool because of this using our own time and fuel. You would assume a brick layer would have tools if they are doing jobs privately - his colleagues excuse was we are just starting up our private buisness. He then started asking for more money and stormed off leaving all the rubbish behind even though we gave him the £300 as agreed prior to the job. The wall itself is okay but again at one point he refused to build up to the top because of a metal screw apparently impossible to remove, so yet again my husband had to assist with the job and removed the screw. Honestly more hassle than it was worth. Also the door was not fitted so now will need to pay someone else to do the job. I do feel bad for them that do not have any equipment but when you pay money for a job you do expect a certain level of service. I wish them good luck in the future and hope they take this advise on board.
UzPro Construction LTD
No reviews yet
Extension Builder in Harrow
Uz Pro Construction Ltd is a London-based bathroom renovation and tiling specialist. We deliver complete bathrooms, ensuites, wetrooms and walk-in showers through one directly-managed team — no subcontracting the job out to strangers you've never met. Every project starts with a free home survey and a fixed price agreed in writing before any work begins, so there are no surprise costs once we're on site. Tiling services: wall and floor tiling to any specification — large-format porcelain, marble and stone-effect, herringbone and metro patterns, fluted and textured finishes. We tile bathrooms and kitchens alike, whether you supply your own tiles or we do, with exact quantities specified up front. We're Constructionline Gold and SSIP accredited, and every job comes with a 24-month workmanship warranty. Our last four bathroom renovations ranged from £11,500 to £16,000 and took two to four weeks on site — real figures from real completed jobs, not estimates. We cover Central and North London and the surrounding boroughs, including Marylebone, Islington, Woolwich, Streatham and Mill Hill. Get in touch for a free, no-obligation survey and a written quotation.
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BUILDING BLUEPRINTS
Rating: 5 out of 5
Extension Builder in Harrow
A highly experienced and qualified contractors from a Carpentry & Joinery background. Taking on diverse scoped projects ranging from Domestic to Commercial.In the residential sector from renovations and refurbishments at the same time carrying many trades in house. We are ready for your project
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Latest review:
Carpentry- 19 Sep 2015
Not only was Ian's quote to do the loft conversion very reasonable, he was very reliable, tidy & very helpful when we had a difficult situation. The work was done in a quick time, when he said he was going to be on site he was, at no time did he let me down. The standard of work was excellent, I would recommend Ian & wouldn't hesitate to use him in the future.
Alpha Global Builders
No reviews yet
Extension Builder in Harrow
Alpha Global Builders started with a simple ambition: to build something meaningful. What began as hands on work in gardens and outdoor spaces grew into a genuine passion for construction, from fences and patios to complete home transformations. Over eight years of experience in the trade, we've learned everything from the ground up. Real projects, real challenges, and real customers who trusted us with their homes. That hands on experience shaped who we are today. Recently, we took the next step and formally established Alpha Global Builders as a registered company, bringing together years of expertise under one trusted name. Today, we specialise in home renovations, loft conversions, house extensions, and kitchen and bathroom refurbishments across North West London. The kind of projects where attention to detail makes all the difference. We've grown, but our approach remains the same: treat every home like it's our own, and every customer like family.
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Darragh Tierney Contracts LTD
No reviews yet
Extension Builder in Harrow
DTC is a trusted residential construction company specialising in home extensions, renovations, loft conversions, and new builds. We deliver true workmanship and solutions tailored to help you create the home you want
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Plastering and painting services
Rating: 5 out of 5
Extension Builder in Harrow
Small family business with years of experience in : *Plasterering@external house insulation, k render, silicone render, sand cement render, damp proof render, skiming. *painting and decorating *tiling /bathroom refurbishment All work will be carried with great quality finish in a tidy manner with best prices you can get on the market.
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Latest review:
Wow, what a service. Needed a room and a half done quickly, Ady responded immediately and gave me his quote and said he could do it straight away. He blew the other quotes out the water, 12 hours later he was at my door material the lot, no fuss just got on with it. Would highly recommend him to anybody looking foe an excellent plasterer. Thanks again Day.
BLG Development LTD
Rating: 5 out of 5
Extension Builder in Harrow
flat roof. PRG ROOF. painting. rendering. ceiling. tiling. plumbing. flooring. windows. bathrooms.,Exstenshens,loft
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Latest review:
Extensions- 24 May 2024
We asked BLG to complete a different job to the one we advertised as weren't ready to start it. Instead they completed a 2 bedroom flat renovation, including ripping out and installation of kitchen, removing plasterboard walls, making good, painting and decorating and recarpeting/tiling. Their work and professionalism was great but even better was their attitude. They were always quick to find good solutions to problems, were extremely accomodating, informative, hard working and prices were very reasonable - at no point did I feel I was being ripped off or being treated like a mug, which after completing multiple renovations in the past am well aware of. I wouldn't hesitate to recommend them.
Rise Up Building
Rating: 5 out of 5
Extension Builder in Harrow
We are loft conversion, extension, roofing and refurbishment experts - transforming spaces, exceeding expectations. At Rise Up Building LTD, we manage projects of all sizes, ensuring a smooth and stress-free experience. We serve all of London. With over a decade of industry experience. We pride ourselves on being fast, precise and personable, leaving you with your beautiful new space. Our commitment to delivering personalised service ensures maximum satisfaction every time. Contact us for inquiries.
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Latest review:
I recently hire rise up building to do my loft conversion, everything was done fast with care and quality, i really enjoyed having this guys around. Love it how they explained every step and every detail about the work. If you looking for some honest and professional contact rise up building, highly recommend them.
Buildwise UK Construction Limited
No reviews yet
Extension Builder in Harrow
At the heart of every successful construction project is a team that understands more than just bricks and mortar. It understands people, purpose, and the importance of delivering on promises. Our company has built its reputation on exactly these principles. We are a trusted construction partner known for reliability, quality workmanship, and a collaborative approach that places our clients’ needs at the forefront of everything we do. With years of industry experience, we have established ourselves as a dependable and professional construction company capable of delivering projects of varying scale and complexity. From residential developments and commercial builds to renovations, refurbishments, and specialist projects, we approach every assignment with the same level of commitment and care. Our reputation has been earned through consistent performance, transparent communication, and a genuine dedication to excellence.
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Your Hubb Ltd
Rating: 5 out of 5
Extension Builder in Harrow
We provide building & electrical services to Clients in London and surrounding counties and pride ourselves in quality workmanship and a professional service putting our Clients at the heart of what we do. Before the start of the project everything is made clear so our Clients know exactly where they stand. Approved by the NICEIC, our Clients are covered by the six year guarantee. All of our work is fully insured and guaranteed. Referencing and site visits are available upon request.
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Latest review:
Electrical- 8 Jun 2020
Thank you for great work. Anthony was very helpful and professional. I would recommend him.
Gks transport ltd
Rating: 4.8 out of 5
Extension Builder in Harrow
Hi A professional people working with utmost care and professionalism
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Latest review:
Bathroom Fitting- 6 Dec 2025
Fixed a long running issue with the toilet. Great job, thank you
Top K Construction and Design LTD
No reviews yet
Extension Builder in Harrow
At Top K Construction and Design LTD, your vision is our project. With over 20 years of experience, we have successfully completed a wide range of projects across London, from new builds and refurbishments to garages and extensions. We are passionate about turning your ideas into reality and prioritize your satisfaction in every step of the process. We love taking on new challenges and working closely with our clients to create spaces that truly meet their needs. Let us bring your dream project to life — quality, reliability, and customer happiness are at the heart of everything we do.
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Pyramid construction
Rating: 5 out of 5
Extension Builder in Harrow
There is father and son business. We do most bricklaying, Extension, garden walls, renovations and home improvements. Experience 15 years. We are reliable and professionals on our job. Happy to give an estimate.
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Latest review:
Bricklaying- 24 Oct 2020
Perfect. ways on time and to the point Egki and his colleague did an excellent job. With thanks, J.

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.