Loft Conversion Companies in Westminster

Name: Loft Conversion Company
Brand: MyBuilder
SKU: loft-conversion-company
Rating: 4.7 (12 reviews)

Easily find verified Westminster Loft Conversion Companies. Just post your job to get quotes from MyBuilder's Loft Conversion Companies in Westminster.

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 loft conversion companies in Westminster

1830 Results

Sort by:

Onyx Services Limited
Rating: 5 out of 5
Loft Conversion Company in Westminster
Onyx services Ltd which is part of the Wigwam construction Group has been in the home improvements business for many years. All engineers are Gas safe and NIEIC registered. We undertake all types of building, construction, plastering, painting as well as heating, plumbing & electrical installations. Onyx has £5 million public liability insurance. All work comes with written garuantee. All major debit/credit cards accepted.
Get in touch
Latest review:
Gas Work- 26 Oct 2025
I was able to get my own boiler and just pay for the extra material and installation. Not all traders accept this. The price was very competitive. I was sceptical at the start but was reassuring on how quickly the job was completed. There was an issue with the thermostat but was sorted out the following week. The gas certificate, building compliance and boiler registration was completed promptly. Would definitely recommend, please allow Shami to quote before making a decision, you won't be disappointed.
ARPconstruction
Rating: 5 out of 5
Loft Conversion Company in Westminster
New on My builder not in bussines. Hello I am Alex, after 13 years working on the construction site 4 years ago i opened my own building company.At the moment I have 12 workers within these 12 works we cover a wide variaty of highley skilled services.I am the director of EvoBuild, and i will be responsible for the work that is carried out.We work monday to sunday to get the job done to a high standard.I will come out and discuss the job in person and endever to answer any questions you may have
Get in touch
Latest review:
Handyman- 23 Mar 2022
Alex and his crew did a fantastic job on my property. They did the work on-time, to budget and to a very professional standard. The work required a wide variety of skills from painting, carpentry, plumbing and electrics. As I was unable to be on site Alex constantly kept me updated on progress with photos and videos. All in all I would highly recommend Alex and his team.
Rise Up Building
Rating: 5 out of 5
Loft Conversion Company in Westminster
We are loft conversion, extension, roofing and refurbishment experts - transforming spaces, exceeding expectations. At Rise Up Building LTD, we manage projects of all sizes, ensuring a smooth and stress-free experience. We serve all of London. With over a decade of industry experience. We pride ourselves on being fast, precise and personable, leaving you with your beautiful new space. Our commitment to delivering personalised service ensures maximum satisfaction every time. Contact us for inquiries.
Get in touch
Latest review:
I recently hire rise up building to do my loft conversion, everything was done fast with care and quality, i really enjoyed having this guys around. Love it how they explained every step and every detail about the work. If you looking for some honest and professional contact rise up building, highly recommend them.
GMC LONDON RENOVATIONS LTD
Rating: 5 out of 5
Loft Conversion Company in Westminster
GMC LONDON RENOVATIONS its specialist in New Builds , Home Extensions , Loft Conversion , Home Renovations and Refurbishment we are committed to providing the best quality workmanship and service. We have experience over 10 yrs in Construction industry Residential and Commercial, we completed successfully many projects during the years where quality was our No1 priority . We holding Public Liability Insurance for customer Peace of Mind and Safety certificates for Gas and Electrical work installation. GMC LONDON RENOVATIONS will deliver from start to finish your project without hassle or delays . We are professionals and enthusiastic young team members.
Get in touch
Latest review:
Bathroom Fitting- 24 Oct 2025
We had 2 bathrooms refurbished at the same time by Romulus and his team over a 4 week period. Both bathrooms were completed on time and on budget. We were looking for 2 functional bathrooms, but ended up with 2 very high spec bathrooms within our original budget, and couldn't be happier with the high level of service and professionalism by all his team. We will now move forward and have his team refurbish our kitchen.
Patrick JR
Rating: 5 out of 5
Loft Conversion Company in Westminster
Experienced Tradesman who enjoys providing a friendly and reliable service to customers. No job too small from Demolition and groundwork’s to first fix of structures to second fix finishing jobs such as hanging TVs and mirrors. Please get in touch for a no obligation quote and estimated timescale.
Get in touch
Latest review:
Handyman- 4 Aug 2021
Great during the pandemic, able to change appointment due to isolation. Job completed in a timely manner and work space left clean. Job completed a month ago and still perfect. Thanks
F&G Design and Build ltd
Rating: 5 out of 5
Loft Conversion Company in Westminster
With a solid foundation of 15 years in the construction industry, our company has established itself as a beacon of excellence and reliability in transforming spaces Specializing in loft conversions, extensions, general building work, and renovations, we take pride in our ability to merge innovative design with impeccable craftsmanship.
Get in touch
Latest review:
Bathroom Fitting- 14 Jun 2026
From start to finish, Darren and Aldi were completely professional and we are really happy with the finished result. They made design suggestions to help us make choices based on their vast experience and worked positively with us. The work was completed skilfully and with care. We would definitely recommend them without hesitation.
P.S. Building Projects Ltd
Rating: 5 out of 5
Loft Conversion Company in Westminster
"WE ARE A HOME EXTENSION AND LOFT CONVERSION SPECIALIST. WE ALSO OFFER A COMPLETE BUILDING SERVICE! A family-run business, Quick growing building company with more than 20 yrs building experience. And we’ve been providing the highest quality work for our customers ever since. Everyone here at P.S.Building Projects Ltd is dedicated to meeting your specific requirements, delivering bespoke work on budget and on time. Which means you’ll enjoy peace of mind from start to finish."
Get in touch
Latest review:
Conversions - General- 11 Oct 2022
We've been seriously impressed with Pawel and his team. They opened up our rear dining room/kitchen wall using an RSJ, following our engineer's drawings perfectly. They also did a few bits of plumbing and bricked up one of the windows at the rear, which is where the new kitchen will be fitted. They were incredibly tidy and really pleasant and courteous to be around, which my wife was so grateful for given we live in a busy family house (most builders are not like this...), I can't thank them enough! We will definitely be using them again in the not-so-distant future!
Clarke's Design & Build Limited
Rating: 5 out of 5
Loft Conversion Company in Westminster
Flawless Finishes - look right here! Clarke's Design and Build are general contractors based in London, serving both the London and surrounding areas of the United Kingdom. Clarke's Design and Build focuses on tailor made home design, residential / commercial renovations and aim to use sustainable, environmentally friendly resources. We specialise in design, extensions, interior/exterior upgrades and aspire to turn challenges into solutions, plans into useful creative spaces.
Get in touch
Latest review:
Carpentry- 22 May 2024
Great work from Leslie! On time, friendly, accommodating of all my questions and paid attention to all the details. Thank you Leslie.
Reinaldo
Rating: 5 out of 5
Loft Conversion Company in Westminster
Hello, my name is Reinaldo Puerta and i owned a building company named Puerta Builders. My team of workers can deliver high standards of finishes, quality and schedules that meet requirements of our client’s expectations. Our company specialises in new construction, refurbishment of existing facilities, loft conversions and house extensions. We are able to offer the lowest rates with greater of quality and services. Puerta Builders looks forward to being part of your Work. Let us help you.
Get in touch
Latest review:
Carpentry- 16 Apr 2017
For a number of reasons, Reinaldo is without doubt the best tradesman I have come across, After having Cowboy Builders ruin my brand new doors. The quality of his work was faultless, he was prompt, always on time and very efficient, his work and work area was always left clean and tidy, and his communication skills, with regards to problem solving and making sure that the work he was carrying out was to my requirements, was excellent. I gave Reinaldo a number of jobs to do over a few separate visits and was not let down once. I cannot recommend Reinaldo highly enough and will be using him again for any future carpentry & joinery works. Reinaldo is not a carpenter however a magician as he can spell his Magic on any given work with a smile.Thanks again ,Reinaldo great work!
Samz Construction Services ltd
Rating: 5 out of 5
Loft Conversion Company in Westminster
We are a small construction firm aiming to provide high quality work. We do new built 'conversion, loft and extension, Refurbishment and all kind of building works. We can manage the building job from start to finish and help the clients with planning, party wall and structural drawings.
Get in touch
Latest review:
Loft Conversion- 7 Aug 2023
I highly recommend Sohail Faisal of Samz Construction Services Ltd. We chose Sohail's company to complete our Hip to Gable with Rear Dormer Loft Conversion in Guildford and we are delighted with the work. The job was completed to a high standard, within the expected timescale and on budget. Sohail's communication throughout is excellent, taking time to explain what work will be completed on which days, what is involved and how many people will be attending on which days to complete the work. Sohail also let me know exactly when deliveries of materials were arriving and when the skips would be collected etc. Sohail's team of builders are all very friendly, polite, and respectful and do a great job of cleaning up after themselves at the end of each day. In terms of price and payment schedule, this was fair and efficient. Sohail has a payment schedule that works really well - invoicing for staggered payments at certain points, i.e. on delivery of materials, then when the building inspector signs off the first job etc. this makes you feel at ease with the job and confident that everything is always on track. All around I am really happy with the project and have no doubts about recommending Sohail to family and friends - I have already asked Sohail to quote on my next project.
Olgert Doko
Rating: 4.8 out of 5
Loft Conversion Company in Westminster
My name is Olgert and my team and I are ready to give you a quote, on any building needs - painting, plastering, tiling, roofing, extensions and many other services. We are friendly, reliable and professional and we care about our work. Give us a call today for a free quote. We are located in North West London and we have more than 15 years experience in construction.
Get in touch
Latest review:
Loft Conversion- 5 Jul 2023
Major refurbishment and reconfiguration project to 3-storey terrace taking 6 months. The building team were: Competitively priced Reliable Hard working Trust worthy And delivered to schedule I would happily recommend them and work with them again
Spectra K&T
Rating: 5 out of 5
Loft Conversion Company in Westminster
Spectra K&T - Powering Your World Need reliable electrical services? Spectra K&T Electrical Service offers expert residential and commercial wiring, installations, upgrades, door entry systems and 24/7 emergency repairs. 21 years of experience. Our licensed electricians prioritises safety and efficiency with every project.
Get in touch
Latest review:
Electrical- 9 Feb 2025
Great job. Fast and clean
Axe Construction Ltd
Rating: 5 out of 5
Loft Conversion Company in Westminster
Hello and welcome to Axe Construction Ltd. If you are thinking of renovating your home, building an extention or arranging general maintenance in your property, we are here to help. Our priority in job is to deliver high standard service to customer’s satisfaction.We offer a professional and friendly service to all private and commercial clients in and around London We are always go above and beyond to satisfy our clients.We are happy to provide references from our clients and arrange site visit
Get in touch
Latest review:
Loft Conversion- 24 Jul 2021
I have to say I was very impressed with Axe from the outset. Ed the project manager clearly knew what he was talking about and was able to come up with suggestions and guidance whenever a decision was needed. He provided an up-front itemised quote, and this was stuck to. The team of workmen led by Avram did an excellent job and I am very happy with the finished product. Avram in particular was a superstar: high quality workmanship, creative solutions to problems, hard-working and most importantly he takes a pride in his work as if it were his own house. Plus, he noticed a tiny leak in the roof unrelated to the project which he fixed at no extra charge. Recommended - I would use them again.
MartinRoofing & BuilderService
Rating: 4.8 out of 5
Loft Conversion Company in Westminster
Professional/qualified Roofer/Joiner/carpenter/handyman/ Fibreglass CYB/BBA/RoofingApprovedContractor/TekSealApproved/NVQ3/ConstructionSkillsCertificationScheme, Roofing/loft/Extension/Floor/ interior work and Decorator/Painter team. Steel welding/Lead work/Structural wood work/Cooperative witch Certificates electrical/ plumbing contractors/Free Quote&Warranty .Many years of experience, friendly cooperation. Clear valuation/Quote. Always find the best solution. Performs only professional work!
Get in touch
Latest review:
Roofing (Pitched)- 14 Nov 2017
Marcin was a pleasure to deal with! He is knowledgeable and professional - he came and explained clearly what needed to done, he emailed me materials' list required and suggested suppliers with product links and he was very helpful at agreeing between us who will be supplying what material. He came and did the job without disruption, in an efficient manner. While he was quick he was thorough to ensure the job is done to a correct standard. He is smart and finds solutions that work. I wish every tradesperson was like him!
Bass Construction Ltd
Rating: 5 out of 5
Loft Conversion Company in Westminster
A multidisciplinary construction firm with a focus on custom construction, Bass Construction/Design was established in 2013. Our team provides services for residential and commercial properties from the planning to construction stages with the goal of creating spaces where functionality and aesthetics coexist.
Get in touch
Latest review:
Extensive work including a double height extension, reconfigured layout on two floors, large area of glazing, roof lights, kitchen and bathroom fitting, laying of a patio and other ancillary work. The work was carried out by Bruno, Roberto and the team to the highest standards with great attention to detail and with care. The completed project was beyond our expectations.
Cappy Construction Ltd
Rating: 5 out of 5
Loft Conversion Company in Westminster
Cappy Construction are specialists in the construction and renovation of residential and commercial properties. We pride ourselves on delivering outstanding quality and design for leading architects and private clients across the Capital, Hertfordshire, Buckinghamshire and Bedfordshire.
Get in touch
Latest review:
Michael and his team provided the highest of quality service. From the site staff to the management staff everyone was helpful and worked very hard, everything ran smoothly with great communication and the result was excellent. The work undertaken was completed to an exemplary standard, I have recommended Cappy Construction to many other people looking to get work done.

4.7

Top rated Loft Conversion Companies

Our Loft Conversion Companies in Westminster, are rated 4.7 out of 5 based on 12 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 services are offered by loft conversion companies in Westminster?

Converting a loft often entails many jobs - some of which you likely haven’t even considered! Fortunately, a professional loft conversion company in Westminster 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 Westminster 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 Westminster

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 Westminster loft conversion company.

Find a loft conversion company in Westminster 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 Westminster.

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 Westminster can view your job and register their interest.

Step 2: Review and compare Westminster 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 Westminster 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 Westminster 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 Westminster

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 Westminster?

A local loft conversion company in Westminster 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 Westminster 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 Westminster 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 Westminster

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 Westminster before agreeing to start the work.

Do I need planning permission for a loft conversion in Westminster?

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 Westminster 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 Westminster loft conversion companies offer strategies to minimise disruption, but in complex projects, temporary relocation may be advisable.