Extension Builders in Harrow, Greater London

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 3.9 (15 reviews)

Easily find verified Harrow, Greater London Extension Builders. Just post your job to get quotes from MyBuilder's Extension Builders in Harrow, Greater London.

Select a service

How it works

Post your job for free

Tell us about your job, and we’ll alert suitable tradespeople in your area. It’s simple and free.

Tradespeople respond

Once your job is posted, you’ll get responses from interested tradespeople through the website.

Review profiles and choose

Browse profiles, work history, and feedback, then choose who you wish to share your details with.

Some of our top rated extension builders in Harrow, Greater London

3211 Results

Sort by:

PEPOSHI
No reviews yet
Extension Builder in Harrow, Greater London
Carpenter
Get in touch
JMG Brickwork
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Fully qualified bricklayer with 16 yrs+experience in bricklaying,I don’t just work on my builder, my main work is for builders in my area and word of mouth recommendations. free quotes for local areas. All Bricklaying works undertaken from new build, extensions, garden walls,porches,anyting with bricks and blocks! Also repairs and repointing from birds beak,bucket handle and weather struck my aim is always to deliver a high quality finish and to the customer’s satisfaction!! please contact for a free quote ,,!!
Get in touch
Latest review:
Bricklaying- 8 Jun 2024
Joe had come to our property to fix the wall. He had done an excellent job and redid the wall to a high standard. He left the area clean and tidy. We strongly recommend getting in contact with Joe for any bricklaying work. Great Job Joe!!
Neville Finnikin
No reviews yet
Extension Builder in Harrow, Greater London
Hi, I'm a builder based in west London with 25+ years experience in groundworks, demolition and general building and landscaping. I have a small team who I work with that are all CSCS certified and very experienced and capable workers. Our aim is to offer high quality work while considering the clients needs in a safe and tidy manor.
Get in touch
Constructum contracts limited
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
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.
Get in touch
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!
Palkin Developments Ltd
No reviews yet
Extension Builder in Harrow, Greater London
We offer high quality construction work at competitive prices, from loft conversions and extensions to full property renovations. We work closely with an architect for every design, meaning we can offer you a truly hassle free end-to-end building service.
Get in touch
LD Building Services Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
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
Get in touch
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.
Sherif Celaj
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Hi, I’m Sherif, a professional builder with over 25 years of hands-on experience in residential construction, renovation, and general building projects. Throughout my career, I’ve built a solid reputation for quality craftsmanship, reliability, and attention to detail. From complete home builds to complex renovation projects, I take pride in turning ideas into lasting, well-crafted results. I’m passionate about creating safe, durable, and beautiful living spaces that meet my clients’ needs and stand the test of time. My experience covers every stage of construction — from planning and site preparation to finishing and inspection — always with a focus on efficiency and precision. Whether working independently or leading a team, I believe in clear communication, strong work ethics, and a commitment to excellence on every project. If you’re looking for a builder who values integrity, skill, and results, I’d be happy to connect and discuss how I can help bring your vision to life.
Get in touch
Latest review:
Restoration & Refurbishment- 10 Dec 2025
Sherif is amazing He communicates regularly during the Job and takes initiative. There were additional works he carried out for us after inspecting and seeing a need . he is kind also even when you make changes to the schedule and goes above and beyond Looking forward to working with him again
Peter Build
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
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!
Get in touch
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.
md building services
No reviews yet
Extension Builder in Harrow, Greater London
Looking to expand your living space? Our company offers comprehensive services for building extensions and loft conversions. We specialize in designing and constructing new rooms or expanding existing ones, and transforming unused attic space into beautiful and functional living areas.
Get in touch
Sarbjeet singh
Rating: 3 out of 5
Extension Builder in Harrow, Greater London
I work in building construction, new building construction and extensions, loft conversion, renovation, driveway, painting & decorating, flooring, Doors hang, skirting, flat roofing, bathrooms, Bespoke kitchen & bedrooms, interior design drawings of rooms and fully house in 2d & 3d views, etc.
Get in touch
Latest review:
Painting & Decorating- 11 Jan 2026
Not done properly, 2days later 2 rest rooms ceiling is falling off
O&L Renovations
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
I've been working in Buiding all my working life. I undertake full referbs and smaller jobs. My work is to the highest standard
Get in touch
Latest review:
Handyman- 3 Sep 2017
Good work, good price and done quickly without any hassle. Highly recommend Jamie and his team.
Bijoux
No reviews yet
Extension Builder in Harrow, Greater London
Honest ,dedicated,Helpful,friendly,experienced...Handymen
Get in touch
Arcadia Construction and Security Limited
No reviews yet
Extension Builder in Harrow, Greater London
Our success comes from over 20 years of experience in delivering quality tradesmanship on timely basis, with our management skill sets ensuring best performance and economies. Our goal is client’s ultimate satisfaction and loyalty. We offer house extensions, loft conversions, interior/exterior refurbishments, bathroom/kitchen renovation, tiling, decorating, carpentry, joinery, landscaping, bricklaying, paving, plastering, rendering and roofing. Security systems installation, CCTV & alarms.
Get in touch
Nomos Construction Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Nomos Group is a well versed contractor covering all aspects of construction from start to finish with more than 40years of combined knowledge and experience in the industry. We aim to remove the stigma of rouge builders 1 job at a time. With a dedicated team of 50 staff members ranging from contract managers, office admin, buyers, estimators, surveyors, architects, engineers, interior designers and site operatives we have all areas covered to take your ideas from inception to completion. Covering London & greater London we can take on jobs as small as a bathroom refurbishment all the way through to a new build development. For that personal touch we offer a Bespoke service to help design your dream home and get all the relevant permissions in place for the works to be completed.
Get in touch
Latest review:
Incredibly impressed with the Nomos teams professionalism and quality of work. They made what would normally be a stressful process very easy and without issues. The attention to detail they provide is second to none and we are extremely happy with the results. Would definitely recommend!
ProNoRth General Builders
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Hello, I am a skilled builder based in North London. With a dedicated team, I offer comprehensive construction services. From small renovations to large projects, I deliver high-quality workmanship and ensure client satisfaction. Contact us to bring your building dreams to life. pronorthgeneralbuilders
Get in touch
Latest review:
Norbi is an exceptionally talented carpenter. He was the team lead on our major building project when we restored our Victorian house over an 18 month period. All his work was superior, from replacing ceilings and ceiling roses, to laying the new herringbone floor with electric underfloor heating. He was always polite, well mannered, and respectful. Norbi takes pride in his work and genuinely cares about the finished result in your home, a rare quality amongst many. We cannot recommend him highly enough.
MFI Construction
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
MFI Construction is more than a building contractor. We are a company with high values to take pride in having a "can do" attitude and in offering superb customer service and support. Large enough to provide a reliable and good value service, but small enough to give you the personal touch you deserve, our skills cover the whole building sector- everything from odd jobs and maintenance to full refurbishments and conversions.
Get in touch
Latest review:
Plumbing- 18 Aug 2026
Worked above and beyond to get the job done, bath panels can be tricky and managed to get it in. Thanks Florin

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.

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, 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.