Loft Conversion Companies in Welwyn

Name: Loft Conversion Company
Brand: MyBuilder
SKU: loft-conversion-company
Rating: 5 (4 reviews)

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Some of our top rated loft conversion companies in Welwyn

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PF building
Rating: 4.7 out of 5
Loft Conversion Company in Welwyn
10 years carpenter/builder Extension, loft extension and new builds Carpentry Kitchens, All roofs, doors, skirting,arch’s, stud walls, flooring, staircases Building work Footing, slabs, patios, fencing
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Latest review:
Loft Conversion- 5 Sep 2020
Paul is very polite, knowledgeable and skilled carpenter. Always in time and with a smile at work. He is very honest with job cost. We will definitely invite him in the future for any jobs we are planning to do, and we would definitely recommend it him to everyone.
RME Construction
Rating: 5 out of 5
Loft Conversion Company in Welwyn
Roofing specialist Flat roofs Roof maintenance Structural work Steel box frames General building Gardening and landscaping Brick repainting Plastering
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Latest review:
Roofing (Pitched)- 30 Nov 2020
Ronan was able to get on-site and investigate the issues raised and propose a sensible and practical solution and the works were completed as agreed on time and to budget. Many thanks for your work and feedback.
UK NAMA Constructions Ltd
Rating: 5 out of 5
Loft Conversion Company in Welwyn
Garden Fencing, Garden Decking, Artificial Grass, Wooden Floor Laminating, Decorating, Partitions.
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Latest review:
Carpentry- 28 Jan 2026
Ali did an exceptional job designing and building our staircase, and I couldn’t be happier with the result. From start to finish, he was a complete gentleman — polite, respectful, and a pleasure to deal with. Ali is clearly a true specialist at what he does. His knowledge, attention to detail, and confidence in his craft really stood out. He was able to design and install the entire staircase in just one day, which was genuinely impressive given the quality of the finish. He worked efficiently, kept the area tidy, and took great pride in his work. It’s rare to find someone who combines skill, professionalism, and good nature so well. I would highly recommend Ali to anyone looking for a high-quality staircase installed by a true expert.
Hunbuild Ltd
Rating: 5 out of 5
Loft Conversion Company in Welwyn
With over 25 years of experience in construction Open Plan Solutions is regarded as one of the most successful companies based in St. Albans and the surrounding counties working on both private and commercial property development. Open Plan Solutions provides a successful track record within a safe environment for the community it works in. Our speciality in providing construction needs makes us the first choice amongst customers looking for quality services. We strive to deliver all construction on time and to budget – and we consistently do, which is why our client base has continued to grow and we consider ourselves to be the number one building and construction experts covering St. Albans, Hertfordshire and surrounding areas.
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Latest review:
Restoration & Refurbishment- 20 May 2026
Excellent service from a very professional team. They removed two chimney breasts for us, turned up right on time, and finished the work to a very good standard. They also did a great job of protecting the house from dust while working. We are very happy with the final result and would definitely recommend them.
Herts Loft Conversions and Extensions LTD
Rating: 5 out of 5
Loft Conversion Company in Welwyn
loft conversions, extensions, general building work, double glazing, carpentry work, 1st fix 2nd fix pitching roofs 35 years as a carpenter very competitive rates no job too small
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Latest review:
Carpentry- 21 Mar 2025
Very pleased, Michael came out and gave us a quote before starting work. He was reliable, professional and kept us up to date daily with what he'd done and what he would be doing next. He cleared up each day allowing us to keep going with everyday living comfortably. We wouldn't hesitate in recommending him to our friends and family 🙂
Alex Powdrell Carpentry
Rating: 5 out of 5
Loft Conversion Company in Welwyn
All carpentry from fitting skirting to building roofs
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Latest review:
Kitchen Fitting- 22 Feb 2024
Alex is a very polite, friendly gent who has done a very good job, going above and beyond what I expected. His workmanship is quality, and it has been a pleasure to have him around. He was very accommodating with changes, and left the place very tidy. I'll happily use Alex's services again.
A-tech Building Services Ltd
Rating: 5 out of 5
Loft Conversion Company in Welwyn
We are a dynamic and profesional construction company, with a vast experience over the last decade and more, offering high quality build at a very competitive price always in mind with the latest legislation in safety and durability.
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Latest review:
Bathroom Fitting- 7 Nov 2025
Amazing work done by Antonel and his colleagues! The job was done to a very high quality standard and they were very thoughtful towards my needs always keeping good communication from the start of the process. Antonel promised me a very tight deadline of 5 days and he made sure this was met, always ensuring the job was done to a very high standard, I couldn’t have asked for more. Definitely someone I would recommend to anyone.
Coste + Beno
Rating: 5 out of 5
Loft Conversion Company in Welwyn
Coste + Beno is an experienced construction business with a strong residential background. We pride ourselves on balancing architectural ingenuity with fine craftsmanship, to offer specialist services to discerning clients in the premium residential sphere. Our bespoke approach has seen us creating bijoux bathrooms in Shoreditch to managing full-scale renovations on listed residences in Primrose Hill. We are looking forward working with you. Best, Coste + Beno
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Latest review:
Architecture- 27 Nov 2017
I contacted Marius because he had good reviews and wanted someone reliable and capable so design a single story extension with large external and internal bifold doors. I wasn’t disappointed - Marius has been excellent throughout the whole design process and produced drawings to a high standard which met our requirements. Marius was an excellent communicator and always available to give advice when required. Further more, he went out of his way to contact local authorities regarding any questions I had at no extra cost to clarify any uncertainties. I would highly recommend his architectural services - he was good value and very professional.
C and T Simmonds Carpentry
Rating: 4 out of 5
Loft Conversion Company in Welwyn
We are father and son with over 45 years experience in all aspects of 1st and 2nd fix Carpentry. No job too big or small. We pride ourselves on doing a good job and having a good relationship with our customers. We have worked on projects ranging from loft conversions, grade listed buildings, total renovations to hanging doors and fitting skirting. We also undertake plastering work, dry lining, flooring, tiling and so on. We do it all.
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Latest review:
Carpentry- 27 Jun 2017
Carl visited and sent a reasonable quote for the work. We discussed some amendments and he re-quoted. All seemed fine and he said he could start the work in July. Then all went quiet. Several emails and txt's were sent with no response. He just didn't respond. So we have wasted several weeks waiting for him when if he had said at the beginning he didn't want to do the work we could have found an alternative builder. But to just not respond is very unprofessional. Gives British builders a bad name.
Oliver Building Services Limited
Rating: 4.8 out of 5
Loft Conversion Company in Welwyn
About Oliver Building Services Ltd, have been fitting kitchen and bathrooms for many years. We pride ourselves on being the go-to bathroom fitters for discerning . We specialise in all bathroom fitting and design services including: Please feel free to get in contact and we will be more than happy to come round to quote •Extension •Kitchen •Bathroom •Installation •Showers •Plumbing •Tiling •Plastering •Electrical •Painting & Decorating • Loft conversion •Roofing
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Latest review:
Kitchen Fitting- 27 Nov 2024
We decided to fit a new kitchen in our tenanted house all done remotely via Australia. We are very pleased with the final kitchen and credit to Oliver for staying committed to the job. He communicated well throughout the process and as a result there were no surprises. This was not an easy process as we were dealing with a difficult tenant that we were trying to remove at the time. As a result the new kitchen was fitted but Oliver had to come back months later to finish the job. I know this was frustrating for him but with mutual respect and trust we got the job finished and I thank him for his patience and honesty. Would recommend his services.
Kite Construction Solutions Ltd
Rating: 4.4 out of 5
Loft Conversion Company in Welwyn
For a local, professional building firm who can work with you and surpass all your expectations shortlist Kite Construction. We will be more than happy to arrange a free site visit to discuss your requirements.
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Latest review:
Loft Conversion- 10 Feb 2016
The work that Kite Construction performed was really excellent and I have been very impressed with their service. We had a set of new stairs installed into the loft area with full plasterwork to the surrounding area, woodwork and plumbing of radiators. The standard of craftsmanship was outstanding and they paid attention to every small detail. I have been delighted with the work and would thoroughly recommend them. Thank you Kite Construction. I will definitely call for your services again in the future.
B-N construction
No reviews yet
Loft Conversion Company in Welwyn
We specialise in all aspects of building, extensions, loft conversions . New builds and all internal carpentry. We pride ourselves on all our work being neat and strong and finished to the highest standard.
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PWD CONSTRUCTION LTD
Rating: 4.9 out of 5
Loft Conversion Company in Welwyn
I established my business to meet the needs of homeowners looking for skilled and qualified tradesmen that put trust at the top of their requirements. From small jobs to large extensions and landscaping we can help to make your property dreams come true. Money back guarantees offered.
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Latest review:
Groundwork & Foundations- 7 May 2026
The job was to build an 8 meter long x 1.4m high cantilever holo block retaining wall. I couldn't speak more highly of Paul and team. He was very professional and engaging on his initial visit. We had structural engineers drawings, which were provided. The quote he supplied exactly matched the engineers spec's and the points we discussed on his visit. It was reassuring to know they spec had been reviewed and would be followed. The work was carried out to an extremely high standard. Paul and team were always on site at the same time and working long days to get the job done. Everything was done properly and to spec (in fact some aspects above the spec the structural engineer provided). Our property was always respected and left clear and tidy every single day. We're extremely happy with the end result. I wouldn't hesitate recommending Paul. Thanks again
JLita Construction
Rating: 4.7 out of 5
Loft Conversion Company in Welwyn
J Lita Ltd Building Service is a business established in 2016. We have more than 10 years' experience in providing building services around North London, London, St Albans, Watford, Luton, Amersham, Aylesbury. We specialise in a wide range of services across all aspects of house refurbishment, construction, including house remodels, renovations, extensions, and more, ensuring that we can handle every aspect of your project from start to finish. We provide expert solutions for projects of all sizes. Our team of professionals is highly skilled and dedicated to delivering exceptional results on every project. We have the knowledge and expertise to get the job done right the first time. At J Lita Ltd, we believe that communication is key to the success of any project. That's why we work closely with our clients to understand their needs and provide customized solutions to meet their unique requirements. We are committed to delivering projects on time, within budget, and most importantly to your satisfaction. We look forward to helping you with your projects. Estimates/quotes are available on request, please don't hesitate to give us a call anytime.
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Latest review:
Loft Conversion- 10 Dec 2025
Having spoken to Jetmir (boss) regarding my project I appointed JLita construction for a loft conversion. I can quite honestly say the service was excellent from start to finish. The team was professional, efficient & delivered good quality workmanship. The project was completed on time and within budget, and the new space looks fantastic. Highly recommend JLita construction for any building work.
Enea Group LTD
Rating: 4.9 out of 5
Loft Conversion Company in Welwyn
Enea Group LTD has undertaken all forms of design and construction work, from Refurbishments, House Extensions and Loft Conversions, to remodelling also for the New Home Builds. In our team we offer a wealth of experience and extensive construction knowledge.
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Latest review:
Loft Conversion- 2 Apr 2023
Excellent customer service and the work provided on site was at the highest. Thanks Naim and the team! Highly recommend.
Skaci & Sons Ltd
Rating: 5 out of 5
Loft Conversion Company in Welwyn
General work from scratch to finish. New Build, extensions, loft conversion, painting, plastering, basement, bathrooms & kitchens. 18 years experience in the trade.
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Latest review:
Loft Conversion- 20 Jan 2023
Eddie and his team ended up delivering my new kitchen which im very happy with and will use the finished results for my work portfollio. Eddie has high expectations and clearly takes pride in the work he delivers which is good for future work

Top rated Loft Conversion Companies

Our Loft Conversion Companies in Welwyn, are rated 5 out of 5 based on 4 reviews from customers like you.

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What services are offered by loft conversion companies in Welwyn?

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

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 Welwyn loft conversion company.

Find a loft conversion company in Welwyn 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 Welwyn.

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 Welwyn can view your job and register their interest.

Step 2: Review and compare Welwyn 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 Welwyn 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 Welwyn 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 Welwyn

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 Welwyn?

A local loft conversion company in Welwyn 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 Welwyn 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 Welwyn 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 Welwyn

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 Welwyn before agreeing to start the work.

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

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