Extension builders in Harrow

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.5 (16 reviews)

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Some of our top rated extension builders in Harrow

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LeveLine General Builders
Rating: 5 out of 5
Extension Builder in Harrow
LeveLine General Builders has grown steadily over recent years. We pride ourselves on customer service and attention to detail. We offer a full architectural and design service to ensure we deliver quality construction projects from start to finish, keeping the customer fully informed at all stages.
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Latest review:
Bricklaying- 27 Feb 2021
Andrew was prompt, efficient and produced high quality work. From the start, he made us feel comfortable we had given the job to the right person. I am extremely pleased we chose to use Andy and I will definitely recommend his services and use again should the need arise. Thank you very much for an outstanding job and pleasant experience.
Vasile Balta
Rating: 5 out of 5
Extension Builder in Harrow
Thank you for reading this I’m Vas( owner of BALTA COMPLETE CONSTRUCTION LTD)from 16 started as a apprentice in construction industry, have work over the years on big projects also small ones , when I was about 30 years old whit lots of experience in house refurbishment, extensions and lofts , decided to open my business, it was the best idea I take Ower focus as a business is a hight quality service, on all projects(big or small) and the feedback from the profile prof this As a person in charge whit the projects, I’m very easy to talk to, friendly , also more than happy to sort issues out Thank you for reading this As a business ower focus is on quality, high end finishes and trat each coustumer whit respect, and live them happy after the project is finished
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Latest review:
Decking- 30 Sep 2026
Vasile replaced the decking on my front and back roof terraces, and I can't recommend him highly enough. His quote was competitive, and though it was several months before I decided to go ahead, he stuck to it and did an excellent job. He was flexible in working around my time schedules and the weather, and when there was some snagging to resolve at the end, he came over immediately to deal with it. He was also friendly and trustworthy throughout. Wouldn't hesitate for a moment before using him again, and neither should you - top marks.
MHA Group Construction Ltd
No reviews yet
Extension Builder in Harrow
London’s finest refurbishment and home improvement company. We offer a wide range of services and deliver projects to the highest standards.
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building_wise
No reviews yet
Extension Builder in Harrow
Looking for a stunning and reliable building to call home or office? Look no further than our top-of-the-line building construction. Our building construction features a sturdy foundation, expertly crafted walls, and durable roofing to ensure long-lasting strength and protection against the elements. We use high-quality materials and top-of-the-line equipment to ensure precision and accuracy in every detail of the construction process.
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rawstraw realty ltd
No reviews yet
Extension Builder in Harrow
Hello We are a team of professional build workers with expertise in Electrics, plumbing, ground works, landscaping and much more
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LONDAMEXP
No reviews yet
Extension Builder in Harrow
Established by industry experts, LONDAMEXP Construction is a London based home refurbishment business. LONDAMEXP Construction combines more than a decade of experience and expertise to provide commendable refurbishment services. We have been in service since the past 15 years in the UK and NL!
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Dragan Construct
No reviews yet
Extension Builder in Harrow
We are 2 Brothers at the hearth of a construction Company experienced in Extensions, Conversions and House Refurbishment
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Pacific Maintenance ltd
No reviews yet
Extension Builder in Harrow
G Maintenance ltd is a family run business who strive to achieve 100% customer satisfaction. We believe that the key to building good client relationships is through not only exceptional quality of work but also through creating trust. To create this trust we meet deadlines and ensure customer satisfaction on every project. We provide a complete property building and maintenance service and have expertise in all elements of the building trade. COMMERCIAL - DOMESTIC - INDUSTRIAL
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b & N Tradind and Contracting
No reviews yet
Extension Builder in Harrow
Building work, new build, extensions,loft conversion and all types of building work
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Luminous builders ltd
Rating: 3 out of 5
Extension Builder in Harrow
At Luminous Builders we bring design, build, and refurbishment together under one roof. We treat every property as a living structure — crafted with care, precision, and integrity. Whether you need a bespoke renovation, detailed interior finish, or full property transformation, our mission is simple: to deliver spaces that inspire, endure, and shine.
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Latest review:
Bathroom Fitting- 26 Feb 2026
Worst job ever. The first day he came at 10.30am started the job left at 9pm said it would take a day & a half. The next day he said he would be here at 8.30am again he came at 10.30am & his words were I’m going to finish in 2 hours maximum. By 3pm he still hadn’t finished & I heard him speaking to someone on the phone saying that he would be there in 45 minutes.then he told me he needed a part for my job & he would be a couple of hours, he came back 4 hours later without a part.Again he was here till 9.30pm. He said he had finished. I went to look and his work was bad. I complained he said he would come back the next day. the next he said he had finished & I told him I wasn’t happy he came back the next day. He tidied up his mistakes.he shaved the bottom of the door off a bit as it wouldn’t close coz of the new tiles & he left, as he was leaving he said please give me a good review. I said I’ll tell the truth & he said but the truth isn’t good. He didn’t stick the threshold back on.
Loftxtnd Limited
Rating: 5 out of 5
Extension Builder in Harrow
Hello! We are offering full range off work:full refurbishment,loft conversion,house extensions,driveway!
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Latest review:
The project lasted from July 2023 to Feb 2024 and comprised of: 1. Single story rear extension with new kitchen and underfloor heating 2. 75m2 patio 3. Internal reconfiguration including removal / installation of walls, new flooring, plumbing (including new boiler), new door frames, doors and skirting, redecoration, carpentry for cupboards 4. Ventilation of existing roof The team are both friendly and professional with Alin always on hand to manage any questions / situations as they arise. The work is clearly costed and every two weeks a valuation takes place to ensure transparency of work undertaken both in original scope and any extras. The quality of the build was excellent, something the building inspector commented on. Alin was recommended to me based on past work, and I in turn would highly recommend him.
MYCO Contractors Limited
Rating: 5 out of 5
Extension Builder in Harrow
I am an experienced and fully insured builder. On average I and my team build and renovate 5 extensions per year. Our current or old clients are always ready to share positive feedback about our work. We work off the ready plans which are usually prepared by the clients themselves and approved by the local authority. As of now (30/03/2023) my availability to start the new project is late April or early May. Please get in touch and I will be happy to assist.
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Latest review:
Extensions- 4 Aug 2020
On a cold November evening, Tony and his team turned up to provide a quote and within a week this was received. The quoted price came in the middle of the pile, which was a good start and aligned closely to the ballpark figure I'd received from a friend who was also in the trade. We then visited a site they were finishing off, and Tony had the confidence to ask us to speak to the client without him there and they gave us the confidence to proceed. They started in January 2020 and rapidly moved through the works and engaged closely with my architect, Structural engineer and building control and proceeded based on their recommendations strictly. We lived in the property as build progressed and the team ensured that the site was secure every evening and we were safe. As COVID-19 hit and we went into Lockdown, the team continued to come and work (we were separated from them as the house was boarded up) and the only challenge was getting supplies. Tony scoured all over London, picking up items as best as he could and work continued. Once they'd broken through into the old part of the house they continued to progress rapidly and showed utter professionalism. The team lead's attention to detail is impressive, and he gave great recommendations on what would be the right approach when we were laying out features such as window sizing and lighting. The standard of work is excellent and I would highly recommend them.
J.J
No reviews yet
Extension Builder in Harrow
Hello, she said, "Hello," she said I try to make every day a happy one with my work I am punctual and conscientious I have an ease of solving problems I provide advice and design
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Tota Builders
Rating: 5 out of 5
Extension Builder in Harrow
Tota Builders are a polite and hard working team, Qualified tradesman, we do commercial and domestic jobs, Our goal is to leave our clients happy with high standard work, We are allso checkatrade approved,and we have been with them for 4 years,
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Latest review:
Carpentry- 23 Nov 2019
Carpenter showed-up on time both days and finished the work ahead of schedule. Nice people and dedicated carpenters. Before living, they cleaned-up all the area and left everything tidy. I would recommend Toptan Tota and would hire them again.
Mannat Construction
No reviews yet
Extension Builder in Harrow
With over 20 years of experience in the building industry, I specialise in high-quality house extensions and loft conversions that add space, value, and long-lasting quality to your home. I take pride in delivering work to a professional standard, with a strong focus on reliability, clear communication, and attention to detail. From the initial design stage through to completion, I work closely with customers to ensure every project is carried out smoothly, safely, and to the agreed timeline. Whether you're looking to expand your living space, create an extra bedroom, or fully transform your property, I bring the skills and experience needed to deliver results you can trust. I’m committed to providing honest advice, transparent pricing, and a clean, tidy working environment. Customer satisfaction is extremely important to me, and much of my work comes from repeat clients and recommendations. I look forward to helping bring your next project to life.
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Artsystem ESSEX Ltd
Rating: 5 out of 5
Extension Builder in Harrow
We are providing high quality general building work like extension,loft conversion,bathrooms,kitchen fitting,plumbing ,completely refurbishment ..... We have ower 20years experiencies and our work is always hight quality. We can also help wiyh garden ,dryway,patio,fence ,roof,.......Dont hesitate ask me about help...
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Latest review:
Handyman- 23 Jan 2023
Would highly recommend....👍 He is a trades person you can trust. I was very happy with the work. He did what he said for the price we agreed upon. Carried out the job on time and worked with great enthusiasm. Seemed determined to solve all problems encountered and cleaned up at the conclusion of the job.Would highly recommend.I felt confident with them working on my property.

4.5

Top rated Extension Builders

Our Extension Builders in Harrow, are rated 4.5 out of 5 based on 16 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.