Loft Conversion Companies in St James

Name: Loft Conversion Company
Brand: MyBuilder
SKU: loft-conversion-company
Rating: 4.4 (12 reviews)

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Some of our top rated loft conversion companies in St James

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S S T Construction UK Ltd
Rating: 4.8 out of 5
Loft Conversion Company in St James
We got skillfull team.I have 16 years experience.
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Latest review:
Loft Conversion- 24 Nov 2016
I had few quotations for my Loft Conversion, but Harvinders price was very reasonable and I went to see his work which was very neat and tidy. During the work he only took Sunday's off and was at my house 8 in the morning and finished the loft in given time.i will definitely recommend him to anyone need work at there place. 5 star ************
15158290 Ltd
Rating: 5 out of 5
Loft Conversion Company in St James
JVS Da-Vinci Builders is a reputable construction company based in Southall, London, with extensive experience in residential and commercial projects. Our skilled team has successfully completed over 30 projects, specializing in services such as loft conversions, extensions, refurbishments, interior design, and custom cabinetry. We are committed to delivering high-quality craftsmanship, exceptional customer service, and innovative solutions that enhance the functionality and aesthetic appeal of our clients’ spaces. Through our meticulous planning, design, and building processes, we ensure that every project is completed to the highest standards and within budget.
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Latest review:
I recently hired Vithesh for a loft conversion, and I couldn't be happier with the results! He completed the project with exceptional quality and efficiency. The structural floor beams and steel structure were flawlessly installed, and the roof comes with a reassuring 10-year warranty. What impressed me the most was his ability to complete the structural job in just 3 weeks, even though the original estimate was 5 weeks. His commitment to meeting deadlines and delivering high-quality work is truly commendable. I’m absolutely thrilled with the outcome and will definitely be calling him for any future projects in my home. Thank you, Vithesh, for a job well done!
Kingston Surrey Construction Ltd
Rating: 5 out of 5
Loft Conversion Company in St James
We are a construction company with over 25 years experience. We Have worked on major projects including extensions, loft conversion and refurbishments. Including smaller projects, new bathroom and kitchens.
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Latest review:
Restoration & Refurbishment- 21 Apr 2024
Got my cloakroom re-done. They r friendly, professional, attention to detail, with clearly tens of years’ experiences. Reasonable rate as well.
Ironbark Interiors
Rating: 5 out of 5
Loft Conversion Company in St James
I have spent the last 15 years working on developing my carpentry skills whilst pushing my design creativity. Creating bespoke kitchens, bedroom, bathroom and all other residential and small commercial Interior work. From concept to design I enjoy and love working with clients to find what is it they really want and what really amazes each of us as individuals. From this point the build to install process is handles with care and passion.
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Latest review:
Tiling- 25 Feb 2026
Job was quoted at a very good price, turned up on time and work was completed to a very high standard! Very happy with the tiling job. Nice tidy work with no mess left behind, would highly recommend Ironbark for your Tiling job.
TNK CONSTRUCTION LTD
Rating: 5 out of 5
Loft Conversion Company in St James
Experienced quality builders. You can rely on us to complete your project weather it’s a straight forward small job or a complicated bigger project with attention to detail.
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Latest review:
Conversions - General- 6 Dec 2024
Amazing builders. Very knowledgeable of building methods and solutions. Very strong and tough guys. Work really hard. Very courteous and patient. Very good results. They replaced a ceiling; built an extension; laid paving stones. All done to complete satisfaction.
Window diy ltd
Rating: 5 out of 5
Loft Conversion Company in St James
More than 15 years experience in the building trade. Carry out all building work from extensions to loft Conversions and renovations. Can assist in planning applications and structural drawings. Fensa Registered Company - More than 15years experience in the glazing field and construction field. Supply and installation of high quality UK made glazing products. 10 year warranty on all installations. Cover all of West London , Surrey, Bucks, North London.
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Latest review:
Windows & Doors (uPVC & Metal)- 29 Sep 2025
Extremely helpful and done the job as requested.
F D SERVICES FULHAM LTD
Rating: 5 out of 5
Loft Conversion Company in St James
The profile of F D services has been enriched by hard-working, highly qualified professionals who always do their very best to achieve excellence in their work. As a result, F D services is a well-established and trusted gas company with extensive experience. Customers are always happy to request our services again and again, as well as to recommend the company.
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Latest review:
Gas Work- 7 May 2024
Florin has done a great job to replace my gas system boiler. He worked hard to finish the job in one day, in fact stayed late evening to make sure the job was completed. He registered the boiler, provided the building reg and Lanlord certificate. I will recommend him based on my experience and will use him again in future.
Luminous builders ltd
Rating: 3 out of 5
Loft Conversion Company in St James
At Luminous Builders we bring design, build, and refurbishment together under one roof. We treat every property as a living structure — crafted with care, precision, and integrity. Whether you need a bespoke renovation, detailed interior finish, or full property transformation, our mission is simple: to deliver spaces that inspire, endure, and shine.
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Latest review:
Bathroom Fitting- 26 Feb 2026
Worst job ever. The first day he came at 10.30am started the job left at 9pm said it would take a day & a half. The next day he said he would be here at 8.30am again he came at 10.30am & his words were I’m going to finish in 2 hours maximum. By 3pm he still hadn’t finished & I heard him speaking to someone on the phone saying that he would be there in 45 minutes.then he told me he needed a part for my job & he would be a couple of hours, he came back 4 hours later without a part.Again he was here till 9.30pm. He said he had finished. I went to look and his work was bad. I complained he said he would come back the next day. the next he said he had finished & I told him I wasn’t happy he came back the next day. He tidied up his mistakes.he shaved the bottom of the door off a bit as it wouldn’t close coz of the new tiles & he left, as he was leaving he said please give me a good review. I said I’ll tell the truth & he said but the truth isn’t good. He didn’t stick the threshold back on.
AVBase Building Services London Limited
No reviews yet
Loft Conversion Company in St James
Avbase Building Services London is an award-winning family business with a deep-seated commitment to transforming homes. With over 20 years of experience in the construction and home improvement industry, we specialise in creating additional space with bespoke house extensions and loft conversions, designed to your unique requirements. Our comprehensive services include meticulous design, thorough planning, and efficient build processes, ensuring a seamless experience from the initial concept to the final touches. Our expertise includes side return projects, offering creative solutions to utilise every inch of your property effectively. We are proud to be known for our reliability, attention to detail, and the impeccable cleanliness we maintain throughout our projects. Serving London, we are committed to turning your house into the home of your dreams.
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Paintworks
No reviews yet
Loft Conversion Company in St James
We are a trusted painting, decorating, full house extension and loft conversion company dedicated to transforming homes with precision, creativity, and exceptional craftsmanship. With a strong focus on quality and attention to detail, we deliver complete property improvement solutions that enhance both the beauty and functionality of your space. From flawless interior and exterior finishes to bespoke house extensions and expertly designed loft conversions, we manage every stage of the process with professionalism and care. Our experienced team works closely with clients to understand their vision, ensuring every project is completed on time, within budget, and to the highest standards. We pride ourselves on reliability, clear communication, and a commitment to exceeding expectations. Whether you’re refreshing a single room or expanding your entire home, we provide results that add lasting value and style.
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Douglas carpentry and building
Rating: 4.9 out of 5
Loft Conversion Company in St James
Douglas carpentry and building has over 10 years experience in all aspects of building work. We as a company have very high standards to accommodate all your building work needs from internal doors, skirting, architraves, built in wardrobes to all general building work. Hard working, dedicated, reliable, clean and tidy and here to give you a fair and honest quote. Please look at previous work on my Instagram page @douglascarpentry23
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Latest review:
Carpentry- 14 May 2026
Replaced a rotten external single door. The existing door frame was reused, as per request. This frame wasn't perfectly square which Alex had to compensate for. Alex arrived on time and completed the work without any unresolved issues, taking all offcuts and old door away for disposal.
Chrisbrickie
Rating: 5 out of 5
Loft Conversion Company in St James
Dear customers I do my best to satisfy my Clients with the jobs they have commissioned to me.
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Latest review:
Extensions- 17 Apr 2019
My extention was left incomplete by a incompetent builder, I had plenty builders coming around for quotes until I decided to go with Peter & Chris after receiving their detailed quote with everything explained in blank and white. I am extremely happy with my choice, as they did a great job finishing the project on time and most importantly great finishes. Peter has an amazing interior design taste, I would definitely recommend picking his brains, Chris on the other hand is very experienced and knowledgeable in building, both work very well together as well as his labourers are very respectful and hardworking. I recommend Peter & Chris to anyone who wants a stress free project. An above and beyond service !
singhbuilder
Rating: 5 out of 5
Loft Conversion Company in St James
Hi my name is Dil Singh, I'm a runing own business with 10years + experience, Multi skilled in all aspects of as a certified electrician, roofing and building.Able to deliver a high standard of work. All new work can be done guaranteed,References avalible on request. I done plenty jobs like electric work: change the consumer unit, wiring, design and inspection and testing, fault finding, loft conversion, extensions. I never let down my customers. Job done guaranteed from a to z by me.
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Latest review:
Loft Conversion- 26 Dec 2019
Working with Dil was a pleasure! From the the outset he was very helpful with calculating overall costs (over and above his costs) for the build to ensure everything had been catered for and was very thorough in checking that my ideas/plans were appropriate for the long term. It was through the initial discussion that some minor adjustments were made and for the better I believe, simple things like where the new Megaflow System should be placed. He was very quick and efficient in identifying where there may be issues upfront and has the right contacts to get things sorted to minimise problems further into the build. I had to get a new mains water pipe installed which to me was a a major job but he got it sorted very quickly through his contacts at a very reasonable cost. His team are very polite and they do a as good a job as possible to minimise impact on your daily living if like us you are living in the property during the process. Essentially a team of 3/4 guys who are capable of doing most things however Dil does call in specialist trade as and when needed to ensure the job gets done in a timely manner, for my build he called in roofers and certified plumbers for the boiler. Only negative is that you have to watch the silicone sealant finishing which is not the tidiest but a minor in the grand scheme of things and if you don’t like something you simply have to say and he will redo within reason. Overall a very happy customer
Seymour Building Services Limited
Rating: 5 out of 5
Loft Conversion Company in St James
Seymour Building Services would look after your complete project. We would organise all our tradesmen so the right trades are there at the right time. This leaves you with no headaches. Just one number to call for our friendly help and advice.
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Latest review:
Kenny and team did a brilliant job replacing my old lean-to porch area for a new smart extension with windows, door and even a cat flap. They were on time, organised, efficient and took away all the old materials and rubbish. Kenny was helpful when he visited and prompt in replying to all communications and supplying quotes and invoices. I am very happy with their work and wouldn't hesitate to recommend their services.
Bexley quality builders limited
Rating: 5 out of 5
Loft Conversion Company in St James
building and carpentry Services . From our services from high end commercial to residential projects ,our extensive experience is in services like loft conversionskitchen setup and renovationshouse extensionback garden patioflooring, bathsnew construction building work etc. We have more than 500 happy and satisfied customers . We offer best price for the services along with flexible working hours.
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Latest review:
Sandeep was very punctual, good communicator and did a nice job. I was pleased with the work and the quote was fairly priced, after some outrageous quotes I got from others. I would recommend Sandeep in the future.
BDS TM Limited
Rating: 5 out of 5
Loft Conversion Company in St James
FULL REFURBISHMENT ,HOUSE EXTENSION AND LOFT CONVERSION SPECIALIST,PAINTING, ELECTRICAL&PLUMBING
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Latest review:
Electrical- 18 Apr 2020
Ben fixed my lights and electrics in garden. He took his time and was punctual. Hes very helpful and resonable. i was very happy with his work, i would recomend him to anyone what a nice man.

4.4

Top rated Loft Conversion Companies

Our Loft Conversion Companies in St James, are rated 4.4 out of 5 based on 12 reviews from customers like you.

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What services are offered by loft conversion companies in St James?

Converting a loft often entails many jobs - some of which you likely haven’t even considered! Fortunately, a professional loft conversion company in St James will be able to handle multiple services, ensuring your transformed loft is fit for purpose.

Some of the services loft conversion companies can provide include:

Full loft conversions: Complete design and build projects when structural alterations are needed
Dormer loft conversions: Add extra headroom and floor space with a dormer extension
Velux or rooflight conversions: Ideal for lofts with good existing height; minimal structural change required
Hip-to-gable conversions: Extend the sloped roof to create more usable space
Mansard conversions: A major structural change offering maximum space.
Loft storage conversions: Add flooring, lighting, and insulation for clean, usable storage
Skylight or roof window fitting: Install natural light solutions like Velux windows
Staircase installation: Design and build bespoke stair access to your new loft
Insulation, heating, and ventilation upgrades: Ensure comfort and compliance with energy standards
Design and planning services: Architectural drawings, planning permission, and building regulation approval

Post your job to MyBuilder and you'll be matched with loft conversion companies in St James who are interested and available to help. And with the reviews of past customers and the freedom to compare the quotes of similar tradespeople, all in the same place, the ball’s in your court.

Average costs of loft conversion companies in St James

Loft conversions tend to be charged on a project basis, rather than by the hour, as they often involve weeks or even months of work.

The cost of your loft conversion depends on a few things, including the style of loft conversion and materials you choose and the size of your property.

That being said, here are average prices for common types of conversion work:

Full loft conversions: £45,000–£70,000+
Dormer loft conversions: £55,000–£85,000+
Velux or rooflight conversions: £25,000–£45,000
Hip-to-gable conversions: £50,000–£80,000+
Mansard conversions: £70,000–£100,000+
Loft storage conversions: £10,000–£20,000
Roof window fitting or skylight installation costs: £1,000–£2,500 per window
Staircase installation costs: £2,000–£5,000
Insulation, heating, and ventilation upgrades: £2,000–£6,000
Design and planning services: £1,500–£4,000

Take a look at our guide to loft conversion costs to get a more detailed breakdown of the different options available when using a St James loft conversion company.

Find a loft conversion company in St James with MyBuilder

When you’re planning major work like a loft conversion, you’ll want to find the right tradesperson for the job. The great news is, MyBuilder has already done all the time-consuming work for you.

All you need to do is post your job on MyBuilder, completely for free, and we’ll share it with loft conversion companies near you in and around St James.

Step 1: Post your job on MyBuilder

Provide a detailed description of your loft conversion project, including the type of conversion you want, any structural changes, preferred materials, and your ideal timeline. Once posted, local loft conversion companies in St James can view your job and register their interest.

Step 2: Review and compare St James loft conversion companies

Browse the profiles of interested loft conversion companies. On MyBuilder, you can view photos of previous projects alongside customer reviews, compare quotes, and see the types of conversions they specialise in.

Step 3: Contact and discuss your project

Once you’ve reviewed local St James loft conversion companies, you can reach out to those that interest you to ask questions, clarify details, and request more specific quotes. At this stage, be sure to discuss vital aspects like planning permission, design options, and estimated timelines to ensure the company meets your requirements.

Step 4: Hire the right St James loft conversion company

Once you’re satisfied with their experience, quotes, and approach, you can confirm your hire and start planning your loft conversion.

You can also take a look at our loft conversion specialist hiring guide to help inform your choice. All tradespeople undergo checks at registration - such as verifying ID documents, company details, and certifications for regulated jobs and doing skill assessments - allowing you to hire with confidence.

Questions to ask local loft conversion companies in St James

Choosing the right loft conversion company for your job requires finding someone who understands your home and your goals.

Find out which company can share your vision by asking the following questions:

What experience do you have with loft conversions in St James?

A local loft conversion company in St James will know the types of properties and building styles common in your area, as well as the planning and building regulations that apply. Ask about similar projects they’ve completed locally.

Are you insured, and do you offer a warranty for your work?

Insurance protects your home during the loft conversion process, while a warranty shows the company’s confidence in the quality and durability of their work.

How do you handle planning permission and building regulations?

Established loft conversion companies in St James should understand local planning rules and building regulations. Ask how they’ll manage permissions, inspections, and compliance to avoid delays or legal issues.

What is included in your quote?

Ensure the quote covers all essential aspects of the loft conversion: structural work, windows or skylights, staircases, insulation, labour, and any additional fees. Understanding this upfront prevents unexpected costs later.

Do you manage the project from start to finish?

Some St James loft conversion companies offer full project management, coordinating architects, builders, and tradespeople. Others may only handle part of the conversion. Clarifying this early on helps you understand what support to expect.

FAQ: Common questions about loft conversions in St James

How long does a loft conversion take?

Typically, a loft conversion can take between 6 and 12 weeks, depending on complexity, planning permissions, and any structural work required. Be sure to discuss the timeline with any potential loft conversion companies in St James before agreeing to start the work.

Do I need planning permission for a loft conversion in St James?

Many loft conversions fall under permitted development, but some require planning permission, especially if you’re adding a dormer, extending the roof, or living in a listed building. A professional St James loft conversion company can advise and handle permissions for you.

Will a loft conversion affect my home insurance?

Yes, you’ll need to update your home insurance to cover the conversion. Inform your provider about structural changes, additional rooms, and any changes to utilities or heating systems.

Can I stay in my home during the loft conversion?

Many loft conversions allow you to remain in your home, though noise and dust are inevitable. Some St James loft conversion companies offer strategies to minimise disruption, but in complex projects, temporary relocation may be advisable.