Extension Builders in St James

Name: Extension Builder
Brand: MyBuilder
SKU: extension-builder
Rating: 4.2 (20 reviews)

Easily find verified St James Extension Builders. Just post your job to get quotes from MyBuilder's Extension Builders in St James.

Select a service

How it works

Post your job for free

Tell us about your job, and we’ll alert suitable tradespeople in your area. It’s simple and free.

Tradespeople respond

Once your job is posted, you’ll get responses from interested tradespeople through the website.

Review profiles and choose

Browse profiles, work history, and feedback, then choose who you wish to share your details with.

Some of our top rated extension builders in St James

3594 Results

Sort by:

Super Services Maintennance Ltd
No reviews yet
Extension Builder in St James
I have been in this business for the past 15 years and usually work all around London. I am Handyman and painting is my specialty. I am perfectionist and very good attention to details.
Get in touch
H & F London Limited
No reviews yet
Extension Builder in St James
H & F London is a specialist construction company based in Hertfordshire & West London. We’re known for providing groundwork solutions & new builds for a variety of clients across London and Hertfordshire.
Get in touch
NDR PROFESSIONAL LTD
Rating: 5 out of 5
Extension Builder in St James
Plastering, Silicone render, plasterboard...
Get in touch
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.
Tota Spark Ltd
Rating: 5 out of 5
Extension Builder in St James
Hi there.I have established this company because I like the work I do and the most important thing is that I want that every client to receive the best of service.I undertake electrical work and general building works.
Get in touch
Latest review:
Electrical- 10 Sep 2019
Nice, trustworthy guy. Quick reply and on time. Will definitely call again next time I need an electrician.
Step-Up Contractors
Rating: 5 out of 5
Extension Builder in St James
Step Up Contractors Ltd with over 20 years of construction experience. We are a family owned business and have been responsible for successfully completing a variety of construction projects covering a wide spectrum of expertee uses. Completed on time, to satisfaction, on budget. We take care of all your construction needs, from design, to handing over keys to your new home. No job too small, from a leaking tap, bathroom install to a double story extension. Free no obligation quotes!
Get in touch
Latest review:
Bathroom Fitting- 14 Aug 2021
I would definitely recommend Step-Up Contractors - they have done a really fantastic and great quality job of refurbishing our bathroom and ensuite shower room. They were very professional, friendly and communicated really well with us throughout the whole process. They tidied up every evening before they left and were very considerate. They did such a good job that we have asked them to come back soon to complete kitchen flooring work for us!
G&j
No reviews yet
Extension Builder in St James
I started my career as decorator in 2019 ,my goal is client satisfaction with a fair price and maintain the quality of my work which I intended to continue.
Get in touch
Gursevaksingh
Rating: 5 out of 5
Extension Builder in St James
Gursevak projects limited For more information about our quality and work follow us on instagram and TikTok @gursevakprojectsltd. myself gursevak Singh. We have more than 5 year experience. We are specialist to providing any kind of house work like digging, foundation,loft conversion, house extensions, bathroom works,paint,tiling paving ,patio slabs etc near london. We are given one year guarantee and good quality of work with good price. thank u
Get in touch
Latest review:
Plastering- 18 Feb 2025
Came to look at the job thoroughly and gave me options. I thought the quote was thoughtful. The guys that visited made me feel confident they knowledgeable and would get the job done as specified. Work completed to high standard, cleared up after themselves. Great job
SC General Builders Ltd
Rating: 5 out of 5
Extension Builder in St James
Welcome. I am a builder with 25 years of experience. Have completed a large number of projects from small jobs to major projects such as extensions, loft conversions and full refurbishments, residential and commercial. Excellent quality for reasonable price guaranteed. Professional, reliable, affordable. Hassle free service. We cover all aspects. Fully insured. Thank you. Seb
Get in touch
Latest review:
Conversions - General- 16 Jun 2024
Excellent communication Good price Did exactly what he said he would do and gave advice on other work that we were doing ourselves Really nice guy Very pleased with his work Would use him again
The Gate Property Management
No reviews yet
Extension Builder in St James
Welcome to The Gate PM – Your Trusted Partner for Complete Home Transformations 📍 Where we work: We cover the wider London metropolitan area, bringing our reliable service to homeowners across London and the surrounding regions. 👷‍♂️ Our experience: With years of hands-on experience in the construction industry, we have successfully completed countless projects ranging from small refurbishments to full-scale extensions. Our portfolio includes everything from listed building renovations to modern loft conversions and new-build extensions. 🛠️ Our special skills: We offer a true one-stop shop for all your building needs. Our in-house team covers: · Full renovations and refurbishments · Extensions, loft conversions, and conservatories · Kitchens, bathrooms, and plumbing · Roofing, flooring, plastering, and tiling · Porch, driveways, and external landscaping · Electrical installations and rewiring · Painting and decorating ✅ Why hire us: We believe in honest communication, transparent pricing, and exceptional craftsmanship. Every project is managed personally from start to finish, ensuring quality control and peace of mind. We're fully insured, pride ourselves on cleanliness and reliability, and won't leave.
Get in touch
MS builder
Rating: 5 out of 5
Extension Builder in St James
My company working in construction field from last 6 years. With the help of many years experience we finish our work with good quality on time and provide customer satisfaction.
Get in touch
Latest review:
MS builder done our house refurbished and renovated, they provide very qualitative work. Their team members are very helpful.
Sami
Rating: 5 out of 5
Extension Builder in St James
Hi, I am a fully skilled plastering with 15 years of experience delivering quality work to your home.I also have experience in all other relating trades like external wall insulation,silicon rendering ect.
Get in touch
Latest review:
Plastering- 28 May 2026
Came on short notice. Completed the job ontime and very nice work
RD PAINTING & RENOVATIONS LTD
No reviews yet
Extension Builder in St James
RD Painting & Renovation provides professional painting and renovation services for homes and businesses. We handle everything from interior and exterior painting to repairs and remodels, always focusing on quality, reliability, and customer satisfaction. Our goal is to make every space look its best and meet the unique needs of each client.
Get in touch
Darko
No reviews yet
Extension Builder in St James
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.
Get in touch
Dexacon Ltd
No reviews yet
Extension Builder in St James
We have over 25 years experience working in construction, covering all areas of the building. With a dedicated team for structural works we can do the majority of work in house. We are also bolstered by a number of incredibly efficient and highly skilled contractors to ensure all projects are completed on time and on budget
Get in touch
Brits construction ltd
Rating: 5 out of 5
Extension Builder in St James
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
Get in touch
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.
A claire
Rating: 5 out of 5
Extension Builder in St James
Hi there I can do anything from A-Z with the best prices and to top quality finish, free estimations is available Best prices you’ll find from me 😜
Get in touch
Latest review:
Tiling- 30 Apr 2026
Job was done to a professional standard. Very satisfied.

4.2

Top rated Extension Builders

Our Extension Builders in St James, are rated 4.2 out of 5 based on 20 reviews from customers like you.

Quality screening

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 St James?

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 St James 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 St James who are available and interested can respond to your post.

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

What are the hourly rates of extension builders in St James?

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

Find extension builders in St James with MyBuilder

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

Step 2: Compare different extension builders in St James

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

Step 3: Hire St James extension builders with confidence

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

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

What to ask a St James extension builder before hiring?

Before hiring an extension builder in St James or extension building company in St James, 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 St James?

An extension builder in St James 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 St James 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 St James?

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 St James 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 St James 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 St James

Can an extension builder in St James help with planning permission?

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

Many St James 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 St James help with materials and finishes?

Yes, most extension builders in St James 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.