Extension Builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.8 (14 reviews)

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Some of our top rated extension builders in Harrow

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Relied on builders ltd
No reviews yet
Extension Builder in Harrow
Hello my name is Costel I have experience in brickwork more then 10 years I have very good reference from customers and proves with photos if you wish to see I Olson have my own company and a van whith tools I have more skills with paving stones etc. And gardening walls and driveway I’m responsible for my work to be everything done..thank you
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TAHIR LTD
No reviews yet
Extension Builder in Harrow
Hi there
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ND constitution
No reviews yet
Extension Builder in Harrow
We have our own company name ND construction we have done job building whole house which includes everything that comes in building work , question I might failed because of language issue but I would recommend you to come on our site to inspect our work thanks
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Arisa renovation LTD
Rating: 5 out of 5
Extension Builder in Harrow
Arisa Renovation LTD is a reliable and experienced building company based in London, offering a full range of high-quality renovation and construction services. We specialise in complete property refurbishments, including house renovations, extensions, and loft conversions. Our services cover all aspects of building work such as painting & decorating, bathroom and kitchen installations, carpentry, flooring, tiling, plastering, and general maintenance. We have extensive experience in structural work, including roofing, framing, and full property transformations from start to finish. Whether it’s modernising an interior space, installing a new bathroom, building bespoke stairs, or completing a full renovation project, we deliver excellent craftsmanship with great attention to detail. We pride ourselves on being professional, punctual, and tidy on every job. All work is completed to a high standard, on time, and within budget. Customer satisfaction is our top priority, and we maintain clear communication throughout every stage of the project. We also offer a workmanship guarantee to give our clients peace of mind. If you are looking for a trustworthy and skilled builder in London, Arisa Renovation LTD is here to help bring your project to lif
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Latest review:
We are extremely happy with the bathroom renovation completed by Arista Renovation LTD. The workmanship is top quality, especially the tiling and finishing details. Communication was clear throughout and the project was delivered exactly as agreed. Would definitely use them again.
Emperor Contractors Limited
No reviews yet
Extension Builder in Harrow
This is a construction company with many connections within the industry. Quality and longevity describes our state of works. We have a portfolio of many projects which all of them have been successful.
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n-vico ltd
Rating: 4.8 out of 5
Extension Builder in Harrow
Marius, as owner of N-Vico LTD has over 17 years experience in the construction industry starting out as a carpenter. Now we are a highly skilled team of builders that provides a complete residential refurbishment service
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Latest review:
Extensions- 21 Jun 2017
COWBOYS! Absolute Nightmare! Marius left the job incomplete, after repeatedly demanding more money before completion! Not to be trusted! Workmanship wasn't as good as he would lead you to believe, I have pics & videos of: Cigarette butts in mortar. Bricklaying in the rain, not water-tight roof/felt work, drainage, unsafe electrical work which needs to be redone. Left my neighbour side of roof damaged + with a hole now for a month. Damaged door/table/gate. Of course, he denies any wrongdoing Please be very careful if you have to use this fraud. Get a FULLY detailed itemised quote! Draw up your own contract - do not use his. Do NOT ever pay CASH. Produce a schedule of works - pay him ONLY when the specific task is 100% complete - leaves lots of work unfinished but then lies claiming its complete at interim payments. Get a FIXED price for every aspect of work - do not have "TBC" or ambiguous costs - if he can charge more - he will. Do NOT use his electrician, cringeworthy attempt to "price up" a simple job and damaged roof. Buy ALL Materials yourself OR require receipts for anything he buys. Request ALL Invoices. Ensure he follows specs - offered me £250 off total job cost, if I used a inferior type of rooflight to the one required in spec. Ensure he doesn't keep rubbish on site, Hire a skip. Keep all communication on record, email, text, even voice record him as he is a pathological liar. Very dishonest, delusional and frankly embarrassing.
Constructum contracts limited
Rating: 5 out of 5
Extension Builder in Harrow
Founded in Twickenham by lifelong friends Alex and Steven, Constructum Contracts Ltd has been delivering high-quality construction and bespoke craftsmanship across Surrey and South West London since 2024. Our combined expertise spans building surveying, project management, general construction and high-end bespoke carpentry — giving clients the confidence of both technical knowledge and practical experience on every project. Steven began his career after earning a Diploma in Construction from Richmond College, working for a respected local builder specialising in loft conversions, extensions and residential renovations throughout the Richmond upon Thames area. While gaining hands-on site experience, he completed a BSc in Building Surveying at Nottingham Trent University. Following graduation, Steven worked for a multi-disciplinary building consultancy in London as a Building Surveyor, Contract Administrator and Project Manager. His portfolio ranged from residential apartment blocks to commercial properties, with particular expertise in the preservation and restoration of historic buildings in Central London. Most recently, he worked in Australia as a private Building Control Surveyor on new-build developments, before returning to the UK to bring his technical knowledge and project leadership back to clients in SW London and Surrey. Alex also began his studies at Richmond College, developing a strong trade foundation in carpentry. Coming from a family of plumbers and electricians, he was immersed in the construction industry from an early age. Over the years, he has refined his skills across multiple trades, including plumbing, electrical works, bespoke cabinetry and kitchen installations. With a particular focus on high-end bespoke carpentry, Alex has worked alongside some of Surrey’s leading cabinetry, wardrobe and kitchen installation companies. He now brings that craftsmanship and attention to detail to every Constructum project. At Constructum Contracts Ltd, we combine professional oversight with skilled workmanship. Whether you require building surveying services, structural alterations, extensions, renovations or bespoke carpentry, we pride ourselves on reliability, transparency and delivering exceptional results with the highest standards of workmanship. We look forward to seeing how we can assist with your project.
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Latest review:
Joinery & Cabinet Making- 9 Jun 2024
Alex has made a great job of our bedroom cupboard. He was reliable, punctual, polite, worked really hard, and cleared up afterwards. The work is of an excellent standard. Would definitely recommend!
LD Building Services Ltd
Rating: 5 out of 5
Extension Builder in Harrow
We are a design and build company based in Isleworth. We are an experienced and disciplined team who have worked on many projects throughout London and surrounding areas for many years. Our company provide professional services to all aspects of building works which includes Loft Conversions, Extensions, Refurbishments & Home Improvements . Federation of Master Builders Trust Mark member
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Latest review:
Extensions- 20 Aug 2016
Fantastic service, Lucas and Darota are an amazing professional team always reliable and our kitchen extension is to an exceptional standard. Darota offers an amazing interior design service. The builders have been punctual, worked really hard and when we have come home from work the house is always tidy so we don't even feel the house is being renovated. We offered LD Property services more work after our kitchen extension/complete refurbishment to include a complete renovation of all our home including garden and driveway. The project has been managed brilliantly as we work full time this has been really helpful.
Tim Alwyn Building Services
Rating: 5 out of 5
Extension Builder in Harrow
Having been in the construction for about 20 years, I take on various jobs like extensions, rebuilds, patios, garden walls and all aspects of building works. Mainly aspects of brickwork and blockwork from the ground upwards.
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Latest review:
Bricklaying- 16 Nov 2024
Tim did a brilliant job rebuilding a wall on our driveway and doing some repointing. He was responsive, reliable and his work was of the highest quality. A real gent. My neighbours and the rest of our road are now after his help!
D T
Rating: 5 out of 5
Extension Builder in Harrow
bathroom fitting Painting and decorating Plastering Carpenter Flooring End of tenancy maintenance extensions .....
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Latest review:
Painting & Decorating- 15 Dec 2025
These painters and decorators were very helpful and finished the job on time and according to my instructions. They also helped me with additional improvements to get the place ready for new tennants. I recommend them for all your painting & decorating needs.
Peter Build
Rating: 5 out of 5
Extension Builder in Harrow
We offer professional service for all your local building requirements. With our team of professionals no job is too small or too big to handle. From Small Brickwork jobs to large extension work, we can do it. Our team of professionals have years of experience and know-how to carry out all jobs to the highest quality without charging extortionate prices.We are a small friendly local Builders with over 20 years experience!
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Latest review:
Bathroom Fitting- 5 Nov 2019
I met up with Peter, told him what needed doing and he provided a detailed quote within days. I handed over a set off keys and basically left him and his team to get on with it! This was a time restricted job, he purchased all the material and provided all the receipts. I returned a week later to find the job completed to the highest standard surpassing my expectations. I will definitely be working with Peter again in the future and I would highly recommend him.
S.A.S Electrical Solutions
Rating: 4.8 out of 5
Extension Builder in Harrow
We are a reliable and friendly business and value ourselves for the quality workmanship we can give you. We are an N.I.C.E.I.C fully approved trained electrical company that covers all aspects of wiring from Domestic or commercial to industrial premises. We have 20 + years experience. We complete and oversee all aspects of building trades to complete various types of projects. We now also specialise in Photovoltaic Solar Installation & Electric Vehicle Chargers.
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Latest review:
Electrical- 30 Oct 2025
Since Steve and his team came on board, the progress on site has improved significantly. Their professionalism, efficiency, and strong work ethic have made a real difference. Steve provided a very fair and reasonable quote, and his approach to the job has been both proactive and solution-focused. Even though the work is still in progress, it’s clear that Steve’s expertise and leadership are helping to move things forward faster and more smoothly than before. His attention to detail and willingness to go the extra mile have been greatly appreciated. I’m very pleased with the results so far and have full confidence that the finished work will be of a high standard. I highly recommend Steve and his team for any electrical work, they’re reliable, skilled, and a pleasure to work with.
XtraForce Limited
No reviews yet
Extension Builder in Harrow
XtraForce Limited are experienced building contractors and fully insured for the works we carry out. We are currently in the process of going through "The Federation of Master Builders" accreditation. We offer whole building packages ranging from extensions to new traditional house builds. We currently work as sub contractors to main contractors doing basement construction, basement conversions to reinforced concrete frames and structural alterations to existing homes to create larger spaces.
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O&L Renovations
Rating: 5 out of 5
Extension Builder in Harrow
I've been working in Buiding all my working life. I undertake full referbs and smaller jobs. My work is to the highest standard
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Latest review:
Handyman- 3 Sep 2017
Good work, good price and done quickly without any hassle. Highly recommend Jamie and his team.
Robert Kastrati
Rating: 5 out of 5
Extension Builder in Harrow
Brick work
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Latest review:
Bricklaying- 18 Jul 2024
Robert is highly professional brick layer, He is polite and communicative. He did excellent job for me. Looking forward to work with his again
Michael O'Carroll
No reviews yet
Extension Builder in Harrow
Bricklayer with over 20 years experience in all aspects of building .
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3.8

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 3.8 out of 5 based on 14 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.