Extension Builders in Westminster

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.2 (19 reviews)

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Some of our top rated extension builders in Westminster

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Loftxtnd Limited
Rating: 5 out of 5
Extension Builder in Westminster
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.
UR BUILDERS
Rating: 4.9 out of 5
Extension Builder in Westminster
Hi ,we are doing every type of construction and building work including electric and plumbing. We undertake all kinds of refurbishments and new extensions ,you can see our finished and running jobs anytime. We have alot references .Our aim is customer satisfaction as we always trying to provide a good service in unbeatable price.
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Latest review:
Extensions- 8 Jan 2025
We hired UR Builders to do our garden room and porch. Sal and his team were amazing, they are hard working and we had excellent communication throughout. His team worked for long hours to meet our tight deadline and produce a highly finished work. We already looking forward to do our next project with Sal and his team. Highly recommended builder
Ava Constructions & Decors
Rating: 4.9 out of 5
Extension Builder in Westminster
Ava Constructions & Decors Ltd is a UK-based construction and renovation company committed to delivering top-quality craftsmanship and reliable project management. We specialise in full refurbishments, extensions, bathroom and kitchen installations, and commercial fit-outs — always tailored to the client’s vision and delivered to the highest UK building standards. With a keen focus on transparency, timelines, and customer satisfaction, Ava Constructions has earned the trust of homeowners, investors, and developers alike. Punctuality and completion of work on time are a priority .Our team always respect the client wishes and work with them to achieve the best possible results to their satisfaction. Thank you in advance
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Latest review:
Extensions- 16 Apr 2026
I would not recommend this builder based on my experience. Instead of using crushed concrete they used soil to fill the house flooring for underfloor heating. 1 The project suffered from poor communication, repeated delays, and a lack of clarity around responsibilities. There were serious issues with the foundation works, which failed Building Control inspection and now require remedial engineering input before works can proceed. The site was also left incomplete and not in an acceptable condition. Despite substantial payments being made, key documentation, technical responses, and follow-through were lacking, leaving me to resolve major compliance and structural issues independently. My experience has resulted in delay, additional cost, and considerable stress. I would strongly advise others to ensure there is a detailed written contract, clear scope of works, and defined accountability
Sandhya Mahadevan
No reviews yet
Extension Builder in Westminster
I am a Structural Engineer with experience delivering structural design for residential and commercial projects. I specialise in alterations to existing buildings, including wall removals, loft conversions, extensions, and steel and timber design. I provide clear calculations, drawings, and practical solutions that meet Building Regulations and site constraints.
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BFG Construction Limited
Rating: 5 out of 5
Extension Builder in Westminster
We Are specialised on all of the trades mentioned below, we guarantee high standard finish and reliable trustworthy works, we provide free estimated to any work. Do not hesitate to contact us, references provided for all works to be undertaken. Thank you.
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Latest review:
Carpentry- 24 Dec 2018
Ben and Genc did a fantastic job. They fitted the fire and smoke strips into my fire door very neatly and cleaned up thoroughly. They were able to come out quickly and it took them no time at all. I am delighted with the result!
Blueprint Developments Limited
Rating: 5 out of 5
Extension Builder in Westminster
Welcome to Blueprint Builders, where your dream space becomes a reality. Nestled in the heart of London, our team is at the forefront of design and construction innovation. We specialize in transforming spaces into luxurious living experiences, with services that include: - Elegant House Extensions - Meticulous Loft Conversions - Comprehensive Renovations - Bespoke New Builds And a wide spectrum of commercial and domestic building projects designed with your luxury and comfort in mind. At Blueprint Builders, your satisfaction is not just a goal—it's our promise. We're dedicated to bringing smiles to our clients faces through meticulous attention to detail, unparalleled craftsmanship, and a seamless client experience from start to finish. Stay connected with our journey of transformation on Instagram @blueprintbuilder. Follow us for a regular dose of inspiration through updated photos of our latest projects. Dreaming of a space makeover? Don't wait any longer. Contact us today for a complimentary site visit and a personalized quote. Let's make your vision a living, breathing reality.
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Latest review:
We recently had our 3-bedroom house renovated, along with a new rear extension build and a garage conversion, and I couldn't be happier with the results. The team demonstrated exceptional craftsmanship and attention to detail throughout the project. From the initial consultation to the final handover, they were professional, reliable, and transparent about costs and timelines. The renovation completely transformed our home, enhancing both its functionality and aesthetics. The rear extension seamlessly integrates with the existing structure, creating a spacious and light-filled living area, while the garage conversion provides a versatile space we can now use as an office. The team was approachable, accommodating any changes we requested during the build, and always left the site clean and organized at the end of each day. I was particularly impressed with their ability to stay on schedule despite some challenging weather conditions. If you're looking for a dependable team that delivers quality work, I highly recommend Blueprint.
Raj
Rating: 5 out of 5
Extension Builder in Westminster
I’m a builder with many trades I will do anything you like
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Latest review:
Demolition- 26 May 2026
Raj and his team did a fantastic job demolishing my concrete shed and brick flowerbed, and really efficiently in the middle of a heatwave! He didn’t reschedule, was honest and really friendly. Top class service, I highly recommend.
Tait build
No reviews yet
Extension Builder in Westminster
Hey Team my names Tait a Carpenter all the way from New Zealand over here in London giving things a go in this great country. Hardworking carpenter with 10 years of experience in the construction industry mainly in residential new builds and renovations. Looking for work in the similar area but can turn my hand at other parts of the trade. Reliable hard working and ready to get stuck in to work.
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TLP Properties Limited
No reviews yet
Extension Builder in Westminster
TLP Properties is a Residential Construction and Project Management company with a presence in London, The Home Counties and Bristol, specialising in high-end residential projects. Our experience is in providing a tried and tested construction service for new builds private homes, small residential developments, apartment blocks, change of use conversions from office to residential, extensions, basements and more
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Darko
No reviews yet
Extension Builder in Westminster
I’m a skilled handyman, carpenter, and joiner with extensive experience in flooring and tiling. Known for building strong rapport with clients, I bring meticulous attention to detail and a deep respect for others’ time. I take pride in every project I undertake, consistently applying my knowledge and refining my craft throughout the week. Reliable, precise, and passionate about quality workmanship.
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NDR PROFESSIONAL LTD
Rating: 5 out of 5
Extension Builder in Westminster
Plastering, Silicone render, plasterboard...
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Latest review:
Plastering- 29 Aug 2025
I asked Daniel to check and price some pebble dashing job. Daniel was fair in his pricing. He was on time in commencing the work as we had agreed. He never left the site until the job was completed within a few days, hence causing least interruptions. I do recommend him and I intend to ask him to carry out works in future.
Brits construction ltd
Rating: 5 out of 5
Extension Builder in Westminster
Brits has vast knowledge & experience of residential projects and has built several Modern Loft conversions, Major Side & Rear Extensions and whole house Internal Refurbishments. We Offer; Project Management. Program of works. Regular Meetings with the client. Liaise with the local authorities. We execute Projects on time, within budget and with the highest quality. Best housekeeping and H&S Standards. Employees & Public Liability Insurances. Member of FMB, LABC, Trust Mark, NABC
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Latest review:
Extensions- 21 Jul 2023
We had a loft conversion and a 9x3m rear extension constructed. We also had underfloor heating, flooring, a new staircase and air con installed. We are happy with the result and would recommend this company. They have also respected warranty and fixed issues that have come up after construction and decorating work completed.
GARDEN AND BUILDING SERVICES LIMITED
New on MyBuilder
Extension Builder in Westminster
We are a reputable company specializing in all aspects of home improvement, including flooring, construction, gardens, electrical work, plumbing, ceilings, and painting. We hope to meet your expectations.
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Albatross Construction
Rating: 5 out of 5
Extension Builder in Westminster
We are a small builder and groundwork company based in South Croydon, with over 30 years building extensions and groundwork experience. Having completed many extensions localy and various groundwork projects. We have all our own plant and machinery which keeps us price competitive and never ask for money up front (unlike some other builders) Our service comes with fully compressive building all risk insurance and all work undertaken is guaranteed References are available on request
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Latest review:
Groundwork & Foundations- 26 Feb 2025
I hired John to build a concrete base for a garden building installation and he did a great job, resulting in follow-on work for him laying a new Indian sandstone patio in front of the building, which he also did to a high standard. After receiving several quotes from different firms, I selected John because he asked the right questions, clearly thought about the solution and was interested in ensuring the result was the right one right for me. He's a lovely bloke and a pleasure to have working here. He works on his own and for the most part keeps himself to himself, wasn't fussed about tweaking the scope here or there as the plan developed and kept the place pretty tidy throughout. I will be using him again for sure, so I wholeheartedly recommend John for any work you're considering hiring him for.
Reli
No reviews yet
Extension Builder in Westminster
Window fitting and painting
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ACAR BROTHERS LIMITED
No reviews yet
Extension Builder in Westminster
It is a design and construction company that operates in London by an Architecture Graduate Huseyin Acar, completing BSc Architecture (2012) and Master of Architecture(2014) at the University of Bath.
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4.2

Top rated Extension Builders

Our Extension Builders in Westminster, are rated 4.2 out of 5 based on 19 reviews from customers like you.

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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 Westminster?

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 Westminster 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 Westminster who are available and interested can respond to your post.

Browse profiles, read customer reviews and get quotes from your chosen Westminster extension builders, all before you decide who to hire.

What are the hourly rates of extension builders in Westminster?

Before getting started with your extension project, it’s important to have a clear budget in place. On average, extension builders in Westminster 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 Westminster extension builders near you on MyBuilder. This allows you to compare what each quote covers and how much your Westminster home extension project is likely to cost.

Find extension builders in Westminster with MyBuilder

Hiring the right extension builder in Westminster 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 Westminster extension builders. Once your job is live, we’ll share it with home extension builders in Westminster who can express their interest.

Step 2: Compare different extension builders in Westminster

When you start receiving interest, review profiles of local Westminster extension builders, check their previous work, and read real customer reviews. Ask about timelines, materials, and request detailed quotes.

Step 3: Hire Westminster extension builders with confidence

After gathering all the information and quotes from your chosen home extension builders in Westminster, 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.

Westminster extension builders are ready to help. Use MyBuilder today to find the right professional for your home extension.

What to ask a Westminster extension builder before hiring?

Before hiring an extension builder in Westminster or extension building company in Westminster, 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 Westminster?

An extension builder in Westminster 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 Westminster 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 Westminster?

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 Westminster 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 Westminster 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 Westminster

Can an extension builder in Westminster help with planning permission?

Yes, many extension builders in Westminster 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 Westminster handle everything from design to construction?

Many Westminster 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 Westminster help with materials and finishes?

Yes, most extension builders in Westminster 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.