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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Daljeet Singh
No reviews yet
Extension Builder in Harrow
We specialize in high-quality bathroom fitting, plumbing, electrical and new home build workmanship. We also do expert fencing and electrical work, ensuring every project is completed to the highest standard.
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Construction
New on MyBuilder
Extension Builder in Harrow
Welcome! My name is Faraj (directer of the company )and I am a dedicated construction professional with experience delivering high-quality residential and commercial building projects. My goal is to provide reliable workmanship, honest advice, and excellent customer service from start to finish. We offer complete construction and renovation services, whether you’re building a new home, extending your property, or refurbishing an existing space. Our team manages every stage of the project with attention to detail, ensuring the work is completed safely, professionally, and to a high standard. Our services include: * Complete house construction * Foundations and groundworks * Brickwork and blockwork * Roofing * Wall and floor tiling * Plumbing * Electrical installations * Carpentry and joinery * Interior and exterior painting and decorating * Full home refurbishments and renovations * General construction and building maintenance We believe in clear communication, transparent pricing, and delivering quality workmanship that lasts. Every project is treated with the same level of care and professionalism, regardless of its size.
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Roman Renovation Service Ltd
No reviews yet
Extension Builder in Harrow
At Roman Renovation Service we are a London based team of professionals providing painting, renovation and property maintenance services to your property (residential or commercial). With a combined team of 5+ years of experience in this speciality and outstanding customer service, we are here to support your needs with great care and attention. We will go above and beyond to make sure the job is done right to your satisfaction! We are able to provide a fast and free quote in person, our professionals are able to visit your property on short notice to provide a free of charge quote in person and advice. We look forward to hearing from you!
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Schs
New on MyBuilder
Extension Builder in Harrow
We’re specialist in plumbing and boiler installation, were also doing good extension building job , were working in Watford , Bromley, harrow, all over london.
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Marios Brickwork
No reviews yet
Extension Builder in Harrow
Expert in restoring brick and stone walls with precise, durable repointing. Using the right mortar for each property, I ensure walls are weatherproof, structurally sound, and look their best. Free quotes and examples of previous work available.
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Max Building Ltd
No reviews yet
Extension Builder in Harrow
Life warranty
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Anamorphic & Co. Ltd.
Rating: 1 out of 5
Extension Builder in Harrow
Anamorphic & Co. Ltd (FMB Certified), the company behind CasaVera Luxury Interiors, is a West London-based construction and interiors firm with nearly 10 years of experience delivering high-end residential and commercial projects across London, Surrey, Berkshire, Hertfordshire and surrounding areas. Our Construction Services - Full house build or refurbishments - Kitchen and rear extensions - Loft conversions - Bathroom installations - Flat and HMO fit-outs - Multi-unit residential developments - Single-room refurbishments - Structural works - Project management What makes us genuinely different is that through CasaVera we supply and install our own bespoke interiors from our 8,500 sq. ft Experience Centre in West London. Everything is manufactured to order and fitted by our own team - no middlemen, no third-party markups, just quality at a fair and honest price. Our Interiors Range - Kitchens - Wardrobes - Bathrooms - Lighting - Internal Doors - External Doors - Wall Panels - Flooring - Staircases Spindles and Handrails - Furniture - Home Decor We are a firm built on trust, accountability and repeat business. The majority of our clients come through referrals, and that says everything about how we work. Company No. 12784775. Fully insured with public liability cover.
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Latest review:
Restoration & Refurbishment- 10 Jul 2026
Never answered any messages after saying they would do the work. Would not recommend.
Prestige Build and Management Limited
No reviews yet
Extension Builder in Harrow
We are a South-East London-based company that specialises in design, bespoke property redevelopments, refurbishment, extensions and loft conversions. We also do roof replacements and create stylish bathrooms and amazing kitchens.
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Maclondonbuilding
Rating: 4.9 out of 5
Extension Builder in Harrow
MACLONDONBUILDING specialist in general construction and renovation services. All kind of house conversions . Our works are performed at the highest standard with attention to the details. Professional team always happy and enjoyed of the work.
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Latest review:
Tiling- 16 Jan 2026
Mac was fantastic and went above and beyond to do the job to a high standard, working well into the evening to get it done. I’d recommend him without hesitation for any work you need doing - big or small. We’re delighted with the finished product.
ANACOND LTD
Rating: 5 out of 5
Extension Builder in Harrow
Throughout the years in construction my father has gathered well balanced team with broad range of experience in every aspect of the job. After acquiring my engineering degree and some experience elsewhere, I re-joined my father once again to provide the service we are both proud of. Our background and experience in construction, design and engineering allows us to provide our clients with high quality service and ensure smooth work-flow of each project. Attention to detail is the key!
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Latest review:
Ground floor rear extension and Loft conversion. First and Second fix works including drainage, structural (block work, wood work and steel work) electrical, plumbing, plastering and tiling. All works completed to a very high standard, we found Arnolda's and his team very helpful, thoughtful and pro-active nothing seemed to be too much trouble for him, we are more than happy with AnA's Construction Developments.
P O'Brien Builders London LTD
No reviews yet
Extension Builder in Harrow
P O’Brien Builders is a trusted, family-run building company with decades of experience delivering high-quality construction services across London. We specialise in home renovations, extensions, loft conversions, and new builds, offering a reliable and professional service from start to finish. Our reputation is built on quality workmanship, attention to detail, and clear communication throughout every project. Whether it’s a small upgrade or a full renovation, we approach every job with the same level of care and commitment, ensuring results that are built to last. As a family business, we take pride in what we do. With the next generation now involved, we combine traditional values with a modern approach to building, giving our clients confidence in both the process and the final result.
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N M Building and Roofing Ltd
Rating: 5 out of 5
Extension Builder in Harrow
Hi we are n.m building and roofing we are a family business that undertake all building / roofing / and / landscaping work all our quotes are free and all work is guaranteed we have many 5 star testimonials for our work we have been working with many happy customers for over 20 years we look forward to hearing from you many thanks Neil N.M building we are also a 5 star approved with trust a trader
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Latest review:
Landscaping- 12 Aug 2024
Neil provided a professional assessment of the job, quoted and carried out the work in a honest and professional manner. Good job tidied up a and provided good advice after the work was completed. I would recommend N M Building and Roofing Ltd
Perpetual Growth Limited
No reviews yet
Extension Builder in Harrow
Hi there, I have over 20 years experience in building extensions, landscaping and bathroom refurbishments.
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Resst Construction
No reviews yet
Extension Builder in Harrow
Resst Construction Ltd has been delivering high-quality construction and refurbishment services since March 2011. With over 100 successfully completed projects, we have built a strong reputation for excellence, reliability, and attention to detail throughout South West and West London. We specialise in high-end refurbishments, transforming properties with exceptional craftsmanship and a professional approach tailored to each client’s vision. From residential renovations to complete property restorations, our experienced team is committed to delivering outstanding results on every project. Resst also focuses on Kitchen extensions, Loft conversions as well As Full house refurbs At Resst Construction, we pride ourselves on exceeding customer expectations through quality workmanship, clear communication, and dedication to client satisfaction.
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SST Homes LTD
Rating: 3 out of 5
Extension Builder in Harrow
Here at SST Homes, we have been providing building services for over 15 years. We take great pride in carrying out all types of building works including New builds, Renovations, Extensions, Loft conversion, Commercial projects, Maintenance contracts and Smart Homes.
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Latest review:
Extensions- 13 Nov 2020
Avoid these traders. They are amateurs and have caused me no end of pain with a small single storey front extension. I sacked them in the end as we just could tale anymore of their slap dash approach.
T De Maio Brickwork services
Rating: 5 out of 5
Extension Builder in Harrow
Our aim is simple, Obtain repeat business and recommendations by providing customer focused services, producing high quality work on time and within budget. Please take a look at my photo gallery of the work myself and the team can produce, our work speaks for itself👍 Kind regards Tony De Maio
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Latest review:
Bricklaying- 28 Jul 2019
With me having no previous experience and knowledge. Toni was helpful and I felt that what ever I asked Toni to do, he could provide. I trusted him completely with what I asked, and he was the best quote by far. Toni helped with where to purchase what was needed and was clear and transparent throughout. I am even thinking of having more work done now I know what can be produce.

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.

Quality screening

Easily find verified local tradespeople. Just post your job to get quotes from tradespeople near you across the UK.

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.