Extension Builders in Harrow, Greater London

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

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

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Innov8 Construction Group Ltd
No reviews yet
Extension Builder in Harrow, Greater London
We are an experienced team of construction specialists with a track record of delivering high-quality new build residential & commercial developments for a range of clients.
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Gagandeep singh
No reviews yet
Extension Builder in Harrow, Greater London
M Gagandeep work as the main work of plumber
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Lnb building solutions ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We are specialise in all types of new builds from large extensions to loft conversions or building a new house with complete planning services with structure drawings and designing interior as well.We are members of federation of Masters Builders. First time buyers with limited funds to decorate and refurbish to give new and bright look with new double glazing and roofing. Every small job is treated like a big job. Thanks in advance for giving us opportunity to fulfill your future home project.
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Latest review:
Extensions- 10 Jan 2023
My wife and I cannot begin to say how happy we are with our experience with LNB Building solutions LTD. Builder/Owner Lokesh was amazing and went out of his way to assist us through the building process. Before deciding on LNB we met many builders and took quotes from 8-10. Lokesh gave us a reasonable quote which was within our budget. The primary reason for us to go with Lokesh, was his passion and the guidance he gave us during our initial conversations. Also working on a project like this, we need to be able to build a good working relationship with the builder and we felt it could be done with Lokesh and I am glad to tell we were right! One of the best things about Lokesh is he is a very trustworthy and transparent person. He tries to save you money wherever he can i.e cost in terms of second fixtures that we were supposed to buy. He advises on the best places to buy stuff and tries to pass on maximum discount via his trade account. Also would like to take this opportunity to give a big THANK YOU to everyone involved in the project especially to the core team which included Jodha, Gagan, Naveen and Luv Singh, who were part of project through out from Day 1 until last day. The project was delivered within the agreed timelines. All our family and friends who have seen the house cannot believe what we have achieved. Thank you to Lokesh and his team for building us our dream home!!
London builders limited
No reviews yet
Extension Builder in Harrow, Greater London
London Builders ltd ??????? 1. General builder/ property refurbishment:: 2. House refurbishmentsRenovations/ Extensions / Garage conversions 3. Loft / Attic/ Basement conversions , shop remodelling 4. New builds 5. Loft conversions 6. Complete refurbishments • All building services ⤵️ ✅Plastering / Skimming ✅Carpentry ✅Brick work ✅Decorating / Painting ✅Roofing ✅Gardening / Landscaping ✅Wooden floors ✅Kitchens / Bathrooms Refurbishments ✅Wall and floor tiling ✅Fencing / Paving / Driveways / Porches ✅Renovations / Extensions / Garage Conversions ✅Loft / Attic / Basement Conversions ✅Heating / Plumbing / Electrics ✅ New Builds ✅. Basements ✅. Loft Conversions ✅ Extensions ✅ Complete Refurbishments ✅ Garage conversions ✅. All Building services ✅ Painting and Decorating ✅ All Plumbing services ✅ All Electrician Services
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R & K Contracting Ltd
No reviews yet
Extension Builder in Harrow, Greater London
R & K Contracting Ltd Amazing building contractors that cover absolutely everything. Where if it’s Exetentions, Refurbishment, New Builds, Plastering & Painting, Bathroom & Kitchen fitting and Many more. We have a lot of experience in the Building Industry with over 12 years experience.
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Harmans gold construction limited
No reviews yet
Extension Builder in Harrow, Greater London
Loft conversion, Brick work, Extensions, Plumbing, Electrical, Kitchen, complete house renovation, Driveway, Porch, Skimming, Block pavement, Painting and Decorating, Bathroom. All construction work.
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D&M CONSTRUCTION BRO. LTD
No reviews yet
Extension Builder in Harrow, Greater London
Over the 25 years D&M Construction Bro. Ltd has grown the business working for clients across London, who only demand the highest level of workmanship and service.Our best domain is quality and trust. Whether you are looking for profesional company to build extension, conversion, full refurbishment or bespoke new build home, we are here to help.
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j &k builders ltd
No reviews yet
Extension Builder in Harrow, Greater London
yes we doing loft conversion on very good price and great work we provide in short time
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Jass
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
We do all kind of staircase with fill finishing, Roofs Structure, Roof Tiles , installing doors , Flooring and other construction work.
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Latest review:
Carpentry- 1 Jul 2026
Jass was quick to respond and gave a good price for fabricating a staircase on site. Jass made sure I was happy before leaving and readjusted one of the steps which was creaking.
CM INVESTMENT LONDON LTD
No reviews yet
Extension Builder in Harrow, Greater London
WE DO ALL TYPE OF BUILDING WORKS .
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Wilson Carpentry & Construction
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
I have been doing first and second fix Carpentry since I left Richmond College in 2002 and successfully completed an NVQ 3 in Carpentry. I started off doing an apprenticeship with my fathers building company (Norson Renovations LTD) where we specialised in lofts extensions, extensions and total refurbs. From hanging doors, and fitting kitchens and any type of flooring. No job too big or too small.
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Latest review:
Carpentry- 14 Nov 2025
Quick reply , reasonable price and job done. Satisfied.
Kallides&sons ltd
No reviews yet
Extension Builder in Harrow, Greater London
Kallides-Sons is a trusted design and build company based in South Ruislip, proudly serving clients across the surrounding areas. We offer a wide range of bespoke services designed to transform both the interior and exterior of your home with precision, creativity, and care. Every project we undertake is tailored to reflect your unique vision, combining functionality, beauty, and lasting quality Our expertise covers full refurbishments, kitchen and bathroom makeovers, home extensions, and detailed interior craftsmanship. Inside the home, we specialise in custom furniture, bespoke cabinetry, and fine woodwork, creating elegant and practical spaces that blend seamlessly with your lifestyle. Each piece of furniture and joinery is handcrafted to order, using premium materials and traditional techniques to ensure timeless appeal and exceptional durability. From concept to completion, our team works closely with you, offering expert guidance and creative insight to achieve results that exceed expectations. Beyond interiors, Kallides-Sons is equally passionate about enhancing outdoor living. We design and build patios, decks, and bespoke garden structures that extend your home’s living space and create beautiful, functional environment
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Alex Mihai
No reviews yet
Extension Builder in Harrow, Greater London
Hello! I have been working in this industry for over 10 years, having experience on building sites and on privat jobs aswell. I also do loft extensions , house extensions , roof refurbishment, groundwork and finishing touches to garden patios!
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Rajput construction
No reviews yet
Extension Builder in Harrow, Greater London
We are experienced and reliable builders specialising in house extensions, structural alterations and refurbishments. We carry out all work to a high standard and in line with Building Regulations. We pride ourselves on being punctual, tidy and professional, with clear communication from start to finish. Fully insured and committed to delivering quality workmanship on every project.
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D&E Smart Building Solutions Ltd
Rating: 5 out of 5
Extension Builder in Harrow, Greater London
Loft conversion. New or refurbished extension. All Carpentry work. New decking or refurbished. Brick walls front of the house, or new building. New or refurbished bathroom, Tilse, Garden, Kitchen, Wood floor, Plumbing with certificate, Electrical with certificate, and much, much more..
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Latest review:
Bathroom Fitting- 7 Mar 2022
Daniel was great and we were impressed by the level of care and detail in his work. Would use him again and recommend to friends.
Ictinus Contractors
Rating: 4.9 out of 5
Extension Builder in Harrow, Greater London
Ictinus Contractors is a reliable London-based building and renovation team, delivering high-quality workmanship across residential and selected commercial projects. We specialise in painting and decorating, wallpapering, plastering and skimming, hard flooring installation, bathroom fitting, and general property improvements. We take pride in providing clean, well-organised work with strong attention to detail from start to finish. Whether the job is a single-room refresh, a bathroom upgrade, new flooring, or wider renovation work, our focus is always the same: quality finishes, honest communication, and dependable service. Based in East London, we cover surrounding areas across London and work closely with every client to make sure each project is completed to a high standard, on time, and with care.
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Latest review:
Painting & Decorating- 6 Apr 2026
I had a very positive experience working with Konstantinos. He is personable, reliable, professional and excellent at co-operating throughout the process. He repainted my entire flat/walls/ceilings to a high standard (and sanded down) he also helped address a few additional repairs along the way. The finish is clean, fresh, and has completely transformed the space. He was thorough and ensured everything was completed properly and on time. I particularly appreciated his attention to detail and his proactive approach in taking care of things I hadn’t even noticed. I would happily recommend Konstantinos and would work with him again in the future! Thank you

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.

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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.