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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Olive Rose Contractors Ltd.
No reviews yet
Extension Builder in Harrow, Greater London
We are two local building firms from London/Essex that merged in 2022 to create OLIVE ROSE CONTRACTORS. We undertake all renovation/building works, including lofts, extensions and conversions. We have tradesman for all services, i.e. electricians, roofers, plumbers. We also provide rubbish clearance services.
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Haarp Building ltd
No reviews yet
Extension Builder in Harrow, Greater London
We are specialised in full renovations,extensions,loft conversions and more . We always make sure we deliver the highest quality of work to make everyone is happy. We also offer warranty on our work and meetings with previous clients and projects
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Jewel roofing & building
No reviews yet
Extension Builder in Harrow, Greater London
We cover all roofing general building works decorating plumbing carpentry kitchen and bathroom renovations at a competitive price. Customer satisfaction is all we aim for. Free quotations for any customer
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A&AK CONSTRUCTION LTD
No reviews yet
Extension Builder in Harrow, Greater London
Hello my name is sandeep kapoor and I am a dedicated builder with almost 12 years of experience starting my journey in this Industry in 2013.Over the years, I’ve honed my skills in various aspects of construction, from residential projects to commercial builds. I’m proud to be registered with Delta membranes , which reflects my commitment to quality and professionalism. I believe in creating spaces that not only meet my clients’ needs but also exceed their expectations. My approach combines meticulous planning, attending to details and focusing on communication in order to run projects smoothly from starting to finish.
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Anthony Rayner
No reviews yet
Extension Builder in Harrow, Greater London
I am a Carpenter by trade, with over 22 years experience. I undertake all aspects of carpentry and woodwork as well as general building, home maintenance and refurbishments.
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Elite Property Projects High Wycombe Ltd
No reviews yet
Extension Builder in Harrow, Greater London
Elite have specialised in creating and improving Homes since 1997. Our skilled trades personnel can assist you with Property Maintenance, Home improvements, Renovations, Roofing, Garden Landscaping, Driveways, Site maintenance/ Supervision and New Builds. We have an extensive portfolio which shows our eye for detail when it comes to the completion of a quality project.
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HSS Construction
Rating: 4.6 out of 5
Extension Builder in Harrow, Greater London
At HSS construction we take pride in delivering high-quality bricklaying services with over a decade of expertise in the industry.I am committed to precision craftsmanship and timely completion, ensuring that every job is built to last. We offer a wide range of services including new builds, extensions, garden walls, brick repairs, patios and landscaping. Hard and soft. Bringing your vision to life through quality building.
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Latest review:
Landscaping- 30 Sep 2025
All good thanks
Diem brickwork and construction
No reviews yet
Extension Builder in Harrow, Greater London
Hi I’m dean from diem brickwork and construction. At diem brickwork and construction we aim to provide the best quality work and make the process stress free we are fully insured with professional and liability insurance and take our responsibility very serious to leave you happy every time we have been trading for 25 years we have lots of valuable customers that would provide reviews
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IVD Construction Ltd
No reviews yet
Extension Builder in Harrow, Greater London
Hello, I’ve been in the construction business for more than 13 years. I’ve been doing high end projects including basement excavation works, new roofs, extensions, full internal renovations, plumbing and electrical works, etc. My company works with high skilled professionals to satisfy all customer needs.
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CCS Complete Construction Services
No reviews yet
Extension Builder in Harrow, Greater London
20+ years experience in the construction industry.Professional Reliable Project Manager for any project, From private small build/refurbishments to large developments. I'm a blacksmith/welder/fabricator.main trade. I have built up a large network of contractors/suppliers/Architects and Engineers along with a wealth of experience,That any project would benefit from.
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Razvan Building Services LTD
No reviews yet
Extension Builder in Harrow, Greater London
Hi .I am Razvan the owner of Razvan Building Services LTD company specialised in full property refurbishment and all aspects of building works .With over 20 years of experiences in building trade and a good portfolio I am waiting for the next challenge . I can provide references from previous customers on request . We cover central , west and south London but we are proud to say we have offered our services outside London : Brighton , Isle of Wight, Walton on Thames
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NSV HOMES LTD
No reviews yet
Extension Builder in Harrow, Greater London
NSV Homes Ltd is a premier residential construction and procurement firm based in Dagenham, serving East London and the Home Counties. Unlike standard builders, we operate a Direct-to-Manufacture Supply Chain, allowing us to deliver high-specification renovations without the "middleman" markups. With over 15 years of experience, we specialise in Full-House Renovations, Extensions, and New Builds, bridging the gap between design and delivery. Our Competitive Advantage: We hold direct trade accounts with the UK's leading manufacturers, ensuring our clients access premium materials at exceptional value: Kitchens: Direct Partner for Burbidge & Son, & Omega PLC, more. Lighting: Specified Partner for Sensio Lighting, more. Flooring: Direct Partner with Victoria Carpets, Riviera Home, and Hugh Mackay, more. Joinery: Bespoke media walls and cabinetry via HUX London, more. Core Services: Rear Extensions & Structural Alterations: From groundworks to steel sign-off. High-Spec Kitchens & Bathrooms: Supply and installation using our direct procurement channels. Full Property Refurbishment: Project managed from concept to completion. Media Walls & Bespoke Joinery: Custom-built using direct-supply materials. Why Choose NSV Homes: We combine the reliability of a family-run contractor with the buying power of a procurement house. We don't just build; we source, supply, and install the highest quality finishes for your home.
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Rabbit General Works
No reviews yet
Extension Builder in Harrow, Greater London
Here at RGW we pride our selves for you the customer. All jobs are undertaken to the highest of standards a standard that we as tradesmen would be happy to have in our own family homes. Not only do we offer the highest of standards but we also offer the most competitive of prices. From full refurbishments,bathrooms,kitchen full garden landscapes and driveways, here really is no job to big or small. Covering all of London and the southeast for the last 10 years we have built up a large portfolio of satisfied customers who never hesitate to get in contact for their las test of projects.
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Loft Haven Ltd
No reviews yet
Extension Builder in Harrow, Greater London
We specialise in a wide range of loft conversion types tailored to different property styles. Whether you’re considering a space-enhancing Dormer, a bright and airy Velux loft, or a full Mansard transformation, we offer bespoke solutions to suit your needs. Our expert team will guide you through every option – including Hip to Gable and L-Shaped Dormers – to find the ideal fit for your home, layout, and lifestyle goals.
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S.R Building & Landscaping
No reviews yet
Extension Builder in Harrow, Greater London
We provide professional construction servos with a focus on precision, durability and quality. Our experienced team delivers expert solutions for projects of all sizes. Our services include: Formwork installation & Reinforced concrete structures: Walls, Columns, Slabs, Foundations, Basement, Decking, Fencing,
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Complex design and build ltd
No reviews yet
Extension Builder in Harrow, Greater London
We are a construction company. We specialise in all types of building works commercial and residential. Over the past years we have built loft conversions, extensions, new build houses and are currently on a commercial refurb building 14 flats.
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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.