Extension Builders in Kings Cross

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.1 (18 reviews)

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Some of our top rated extension builders in Kings Cross

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REA Construction LTD
Rating: 5 out of 5
Extension Builder in Kings Cross
The company’s success is built on the strong belief of quality work, attention to detail and on-time completion. Rea Construction Ltd has an in house team of builders, architects, and interior designers with all the relevant skills and qualifications which enable us to offer a fully comprehensive design and build service. Get in touch today for a free on site consultation.
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Latest review:
Extensions- 8 Dec 2017
We couldn’t be happier with the professionalism and quality of workmanship from REA Construction. The project was delivered within budget and on time. We lived in the property during the work and we, our neighbours and the site were always treated with the utmost consideration. There were almost no hitches and, when they did occur, they were dealt with immediately and thoroughly. Our project team, led by Kristjan and Besi, were universally hardworking, organised and produced work to an excellent standard. Communication is great, the people are wonderful. Renato was someone I felt I could trust from the moment I met him and he never let us down. He and everyone at REA genuinely care about what they do and that their customers have a happy experience. We certainly did and would have no hesitation recommending them to others.
Done By Tom Ltd
Rating: 5 out of 5
Extension Builder in Kings Cross
Welcome to Done by Tom – we offer a completely bespoke design and build service for the London private sector. If you’re looking for clever, stunning and energy-efficient construction as well as interior design, we are it. At Done by Tom, we’ve come up with a unique success formula when it comes to memorable design and construction: combining the interior design, architecture and construction process into one seamless dream to deliver according to our clients vision.
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Latest review:
Fireplaces & Flues- 13 Nov 2017
i was so so happy with the service completed by done by tom. I had a really urgent last minute job and they were able to complete all the work to a really high standard and with a great price. I would trust them to do any building work in my house and am happy to have found a trusted builder for future works. Would recommend to anyone
Kalafuldeco
Rating: 5 out of 5
Extension Builder in Kings Cross
❌ We Turn Houses Into Kalaful Homes ❌ 350+ REVIEWS / 5 STAR RATING X⭕️X - WE'LL MATCH ANY REASONABLE QUOTES - X⭕️X Hi, This is Cristina in The Office. We Specialise in Flooring / Painting Int / Ext Building Services - Kitchens / Bathrooms / Lofts / Extensions.etc +£25 Each - Plane / Trimming Doors if required +Removal £50 - £75 Each Room + Disposal £100 - £300 If Required FLOORING ESTIMATES / WE ALSO DO PAINTING Fitting Beading / Scotia is Free, Inc in the Job Fitting Skirting is Min £200+ / Hallway Min £250+ Kitchen / Bathroom Min £200+ Laminate / Lvt Click ( Sub Floor Must be Reasonablly Level ) Straight Runs - £20m2 / Inc Hallways £25m2+ MIN £100 UPTO 5m2 Engineered Click Straight Runs - £25m2 / Inc Hallways £30m2+ MIN £150 UPTO 5m2 Hardwood T&G / Tongue & Groove Straight Runs - £30m2 / Inc Hallways £35m2+ MIN £200 UPTO 5m2 Herringbone - £40 - £45m2+ Cash Deals + 20% on Bank Transfer or if Invoice is Required - Payments To be Made End Of Each Day ❌ Must be Able to Provide Off Street Parking / Permits as The Crew Needs Access to The Vehicle at all Times. Thanking you in Advance Christina & Kam @ Kalaful Deco PAINTING ESTIMATES PAINTING ONLY - NO WALLPAPERING We also do Flooring / Gardening / Man & Van + Handyman Jobs Single Room - £300 Inc Minor Filling & Sanding / All White ) + £75 / 2 Colours / Woodwork £50+ £150 Extra To Paint on Fresh Plaster Living / Double Room - £400 Inc Minor Filling & Sanding / All White + £75 / 2 Colours / Woodwork £50+ Hallways- £450 - £750 Inc Working around 4-8 Doors Thanking you in Advance Christina & Kam @ Kalaful Deco
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Latest review:
Hard Flooring- 8 Sep 2026
The floor has turned out perfectly, Kam did a great job! Thanks Kam!
Don & Dorian Limited
Rating: 5 out of 5
Extension Builder in Kings Cross
We are Don & Dorian Limited. We are a family run business based on the corner of Central London in Islington. We have a combined experience of 40 years between us. We specialise in interior renovations, loft conversions, extensions and new builds. We usually undertake a project fully from start to finish as we have many in-house trades from plumbers and electricians to carpenters and painters. We pride ourselves with the quality of work we produce and thoroughness.
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Latest review:
Extensions- 17 Feb 2022
Don and Jake were terrific. Nothing was too much trouble and they provided work to a very high standard. They were extremely competent and I cannot recommend them highly enough. I have done many building projects and they were the first builders that I didn't fall out with!
CM Building LTD
Rating: 5 out of 5
Extension Builder in Kings Cross
At CM Loft Conversions, we specialise in luxury loft conversions, home extensions, and full refurbishments for both residential and commercial properties across London. Our dedicated team is renowned for transforming spaces with unparalleled craftsmanship and meticulous attention to detail. Whether it’s a high-end home, a modern office, or a commercial property, we deliver projects that elevate both form and function. By seamlessly blending design innovation with practical solutions, we ensure every project not only enhances the aesthetic appeal of a space but also maximises its value and usability. At CM Loft Conversions, we are passionate about creating bespoke spaces that reflect the unique needs of our clients. From concept to completion, we focus on the fine details and provide a smooth, stress-free experience. Whether you’re looking to transform your home, expand your business premises, or refurbish a commercial unit, our team is committed to delivering results that exceed expectations.
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Latest review:
I met Charlie and his team from CM Builders Ltd when they were completing a loft extension and ground floor extension for one of my neighbours. Quotation and budget I was given an estimate subject to drawings as I was on a strict budget that I had to keep to for the build. Charlie was able to help me keep to the budget, both at the final agreed plan and during the build. The project was complex in that whilst it was a loft extension, all of the house was rebuilt. The only thing kept was the external walls and first floor rafters. Whilst the footprint of the first floor was not being changed I wanted to bring it up to current building standards with extra insulation. All of the plumbing and electrics were also replaced including a new boiler. The overall build has come in on budget, save for agreed enhancements that I did not think of at the planning stage and or building regulations such as double ceiling fire plaster boards. There were also items such as the original stairs that I wanted to keep, but Charlie was able to increase the height space in the kitchen making the worktop much more usable for tall people for a larger part of the kitchen. These were suggested to me as potential options as part of the build. Stage payments The stage payments have all been sensible throughout the build and linked to the ongoing work schedule. I have not therefore had any concerns in this regard. Quality of work This was a very complicated build as unlike the ground floor the first and new second floor are “L” shaped. The new 2nd floor included an en-suite and 2 bedrooms. Overall the house has been increased from 2 bedrooms 1 bathroom, to four doubles and 2 bathrooms. The quality of work is excellent and Charlie project manages his team to ensure that they all deliver to a high standard- if it is not done correctlt they do it again, with Charlie spotting any issues. Timeline of build This has generally gone to plan very well. As with any build you have to be realistic as things will happen outside of anyone’s control. When issues have arisen Charlie manages them to a conclusion. Also be realistic if you are having to manage to a tight budget. I had to plan for various stage receipts of cash before I could order the kitchen and bathroom items - make sure you understand how this impacts the build and availability of the work force, recognising that CM Builders have to book kitchen fitters and plumbers. CM Builders are also very helpful in that they have sorted out issues with the brick work of my freestanding garage (nothing to do with the build) and also a neighbour’s wall that could have been dangerous to the public, should it have failed. Conclusion The whole family are very pleased with the outcome and we now have the equivalent of a brand new house that has been built to a very high standard. This has definitely been worth doing both from a valuation perspective and quality of life perspective. I would not hesitate to instruct Charlie and his team again.
rfi builders ltd
Rating: 5 out of 5
Extension Builder in Kings Cross
Hi! My name is Rifat, I’m the proud owner of RFI builders. I have 30+ years experience in the construction industry having done jobs in, brick laying, plastering, flooring, painting, loft conversions, extensions and many more!
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Latest review:
Plastering- 4 Oct 2024
Mr Rifat did an excellent job for plastering rooms and i would recommend him to everyone highly. The work he has done is to a very high standard and completed in 3 days. His quote was very helpful and comprehensive and he was helpful and very kind and calm. He did not take a break from doing the work, even though i told him to take a seat for 5-10 minutes. He is a very hardworking person. I think anyone to catch him to do a job for themselves is very lucky. I recommend him to everyone because he knows how to do good job.
Raj
Rating: 4.4 out of 5
Extension Builder in Kings Cross
For all your building needs: Extension • Loft • Bathroom Renovation Tiles Work - Plumbing • Electrical - Roofing Painting • Garden Work and repair work. House renovations and kitchen renovations.
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Latest review:
Restoration & Refurbishment- 12 Jun 2026
Hired to finish off a complete flat renovation - work mainly consisted of painting, some remedial repair work, light carpentry and a snagging list. Whilst Raj and his guy were great at light repairs, handyman and carpentry work (which is the only reason I’m even rating them with stars), their attention to detail and completion of the snagging list was very poor! Despite having discussions with me to rectify things after I showed him examples, the flat is now left with uneven paint edges, drip marks, uneven grouting, unpainted architraves and sloppy silicone work. Whilst they are good at some things, decorating is definitely not one of them, so it’s a shame and disappointing.
W.A. Brown Builders LTD
Rating: 5 out of 5
Extension Builder in Kings Cross
I have been in the building industry now for over 40 years, I started as a buidlers labourer back in 1983 for my uncle, working on houses and in offices in the maida vale area.
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Latest review:
Carpentry- 20 Jul 2024
Wayne and his team did a great job. Communication and planning was effective from the start, and stuck to the deadline that was set at the beginning of the project. I’d definitely hire again for my upcoming projects.
PLANNING APP LTD
Rating: 5 out of 5
Extension Builder in Kings Cross
We create architectural drawings. We are specialised in applications for planning permission and building regulations and co-operate with local structural engineers for structural calculations, party wall surveyors and building companies. Our projects include extensions, lofts, garages, house&flat conversions in different councils all around London. If you are thinking of extending, converting, or splitting your property do not hesitate to contact us for a free first consultation & quotation.
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Latest review:
CAD / Drawings- 23 Sep 2020
Marius has been doing a great job and put in an extra effort to ensure we were happy with the outcome. I can not recommend Marius highly enough, especially as he managed to fix an issue with the council that we had from someone else drawings. He was patient and very well prepared. Went an extra mile and gave us different ideas/options. He was flexible with timings and most importantly with price. Had by far the best quote and did an exceptional job.
Plastering and K rendering
Rating: 5 out of 5
Extension Builder in Kings Cross
🏗️ General Builder • Roofing • Extensions • Refurbishment – London Looking for a reliable and professional builder in London? We provide high–quality construction and renovation services at competitive prices. ✅ Plastering & Insolation Silicone Rendering ✅ Our Services Include: • General Building & Refurbishment – Full house renovations, kitchen & bathroom fitting, plastering, flooring, painting & decorating. • Extensions – Single & double-storey extensions, side returns, rear extensions, loft conversions, and garage conversions. • Roofing Services – New roof installations, flat & pitched roofs, roof repairs, waterproofing, guttering & fascias. • Structural Work – Brickwork, concrete, foundations, and load-bearing alterations. 💪 Why Choose Us? • Experienced team with over 16 years in the trade • All work guaranteed & fully insured • Competitive, transparent pricing • Clean & reliable service – we treat your home with respect • Free, no-obligation quotes 📍 We cover all London postcodes – Central London,North, South, East & West.
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Latest review:
Plastering- 16 Mar 2020
Almed and his team came over to see the two bungalows and gave me a quote and was more reasonable than other quotes I had previously. Almed started the job and stated exactly what he was going to do from the beginning to the end of the job. He is a very professional and knowledgeable person and he and his team did a outstanding plastering job on my two bungalows and I’m very happy with the job and will highly recommend him for future projects. Thanks Zai
A. plastering
Rating: 5 out of 5
Extension Builder in Kings Cross
Hi. My name is Fatos. I have been in construction for over 17 years. We undertake rendering, plastering and painting jobs. High standard finish in very competitive prices. We also do loft conversion,roofing, plumbing, electric, tiling, extension ect. Our prioritie is to get the job done in very high quality
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Latest review:
Plastering- 22 Oct 2024
We needed to plaster our house ASAP and Fatos completed it in a short time. The house looks amazing, he was quick, efficient and was a great communicator. I would highly recommend him.
Himanshu
Rating: 5 out of 5
Extension Builder in Kings Cross
Whether you're looking to modernize your home's exterior, improve insulation performance, or create a stunning brick-effect finish, we provide tailored solutions that combine aesthetics, durability, and long-term value. Contact us today to discuss your project and arrange a free consultation.
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Latest review:
Insulation- 16 Sep 2026
I hired Himanshu to do my external insulation work and I was more than pleased with the work he did. He paid attention to details, he was patient with the job. Himanshu and his team were always on time and fast as well. They did an exceptional job on my property. I am definitely hiring him again for any building and insulation works. I highly recommend working with him.
Malkeet1construcstion
Rating: 5 out of 5
Extension Builder in Kings Cross
“Hi, I’m Gurpreet singh. I’m a qualified builder with 7 years of experience in residential and commercial work. I specialise in all type of building work such as renovations, extensions, and general building. I take pride in quality workmanship and reliable service.”
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Latest review:
Bathroom Fitting- 6 Sep 2026
Very happy with the work carried out by Gurpreet. Honest, reliable, professional and reasonable prices. I have no hesitation in recommending his work. New bathroom and kitchen fittings, painting and decoration.
My Home Services London Ltd
Rating: 5 out of 5
Extension Builder in Kings Cross
My Home Services London Ltd is a professional construction and home improvement company specialising in bathroom and kitchen renovations, house extensions, loft conversions, and full property refurbishments. We also provide expert gas, electrical, electronics, and smart home (domotics) installation and maintenance services. Our team delivers complete, high-quality solutions designed to transform homes by combining functionality, comfort, style, and modern technology. From small upgrades to large-scale renovation and extension projects, we work with a safe, reliable, and professional approach tailored to each client’s needs and vision.
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Latest review:
Handyman- 29 May 2026
Absolutely fantastic service, they did a great job!!! Friendly and professional. I look forward to having them back for more jobs. 100% highly recommend!! Thank you very much!
SEASOUTH BUILDS LIMITED
Rating: 5 out of 5
Extension Builder in Kings Cross
At Seasouth Builds, we bring over 5 years of hands-on experience in the building and construction industry. Known for our loyalty, reliability, and attention to detail, we take pride in delivering high-quality workmanship on every project
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Latest review:
Tiling- 24 Sep 2025
I hired seasouth builds because not only did he give a really reasonable quote, but he also had knowledge of tiling over retrofit underfloor heating - which other tilers seemed to be really hesitant to work with. The job was done to an excellent standard - he’s a real perfectionist. It did take a bit longer than expected, due to some floor level issues which he didn’t account for when he quoted. I was really worried about the price increasing out of my budget when we started running over time, but I was so grateful to find that he was a really honest guy who stuck to the agreed quote and didn’t try to make it my problem one little bit. He was polite and friendly throughout the whole job, turned up whenever he said he would, and kept in constant contact. Really honest (I happily left him unattended in my property). Customer service was excellent, nothing was too much trouble. 10/10 would recommend.
Victoria Urban Contractors LTD
Rating: 5 out of 5
Extension Builder in Kings Cross
we pride ourselves on being builders and contractors that are synonymous with high-quality, skilled craftsmanship. We provide a full range of building services in London, from renovation to restoration and site management. No matter how big or small your project is, our approach is always the same – focused, professional and with true attention to detail.
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Latest review:
Extensions- 18 Sep 2024
I looked at 5 quotes and was so happy to have chosen Elvis and his highly experienced team. They did an excellent job of building a new 11sq meter garden rear extension. This was a bit complicated project because it’s a listed house. Elvis and his team were hardworking, always responsive and came up with great solutions when necessary. I am very pleased with the high quality end result. I would use them again and can't recommend them enough! Great job done

4.1

Top rated Extension Builders

Our Extension Builders in Kings Cross, are rated 4.1 out of 5 based on 18 reviews from customers like you.

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What types of services are offered by local extension builders in Kings Cross?

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 Kings Cross 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 Kings Cross who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in Kings Cross?

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

Find extension builders in Kings Cross with MyBuilder

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

Step 2: Compare different extension builders in Kings Cross

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

Step 3: Hire Kings Cross extension builders with confidence

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

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

What to ask a Kings Cross extension builder before hiring?

Before hiring an extension builder in Kings Cross or extension building company in Kings Cross, 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 Kings Cross?

An extension builder in Kings Cross 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 Kings Cross 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 Kings Cross?

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 Kings Cross 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 Kings Cross 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 Kings Cross

Can an extension builder in Kings Cross help with planning permission?

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

Many Kings Cross 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 Kings Cross help with materials and finishes?

Yes, most extension builders in Kings Cross 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.