— Service Details
Loft Conversion London
Transforming Homes in London
Turn the space above your head into a beautiful, functional living area with a bespoke loft conversion from New Build Contractors. We design and build high-quality loft conversions across London, from master bedrooms and home offices to en-suite guest suites and studios. With London property prices at an all-time high, moving isn’t always the answer. A loft conversion is a smarter, more cost-effective way to get the extra space your family needs and add up to 20-25% to your property value. Whether you live in a Victorian terrace in Clapham, a 1930s semi in Ealing or a detached in Hampstead, our team will guide you through every step from the initial survey and design, through planning and permissions, to the final build.
At New Build Contractors, we turn underused lofts into beautiful living spaces across London. Whether you want a spacious master bedroom, a bright home office or an extra bedroom for your growing family, a loft conversion is one of the most innovative ways to add space and value to your home.
With London property prices still rising, moving to a bigger house is expensive and disruptive. A well-designed loft conversion allows you to stay in the area you love, create the space your family needs — and it’s often much cheaper than buying a bigger property.
We handle everything from the initial survey and design through to planning permissions, party wall agreements, and construction and finishing. With fixed pricing, a 10-year structural warranty and a dedicated project manager on every project, you can trust us to deliver your loft conversion smoothly, on time and to the highest standard.







— Process
Our Loft Conversion Process
We know taking on a loft conversion in London can feel like a big deal. From dealing with local planning rules to managing building works in busy residential streets, it can be overwhelming. That’s why, at New Build Contractors, we’ve developed a straightforward, step-by-step approach that’s stress-free, transparent, and under control.
Initial Consultation & Site Survey
Every project starts with a free, no-obligation consultation at your home. We’ll discuss your ideas, assess your roof space, and explore the possibilities. Our team will consider the character of your property, whether it’s a Victorian terrace in Balham, a 1930s semi-detached house in Ealing, or a modern townhouse in North London, to advise on the type of conversion that will work best. We’ll also highlight any constraints, such as head height, access or conservation area rules, right from the start.
01
Architectural Design & Drawings
Once you’re ready to move forward, our in-house architects will prepare detailed plans tailored to your lifestyle and needs. We’ll maximise natural light with skylights, dormer windows or Juliet balconies and design layouts that make the most of every square metre. For families this might mean a spacious master suite; for professionals a quiet office; or for landlords an extra rental unit. Because London homes are so varied, we focus on blending your new loft in with the style and character of your existing property.
02
Fixed Quotation & Starting the Build
Once your designs are approved, we’ll provide a detailed, fixed-price quotation. This will include a breakdown of all works, materials and finishes so there are no surprises. Our skilled construction team will then bring your plans to life. We work with care and respect for your home and your neighbours, mindful of the close living conditions of London streets. Regular progress meetings and on-site inspections ensure everything is completed to the highest standard, structure and finish.
03
Completion and Handover
Once your loft conversion is complete, we’ll do a full quality check and provide all the necessary documentation, including Building Control certificates. Every project comes with our 10-year structural warranty, ensuring you have peace of mind that your investment is protected long after the project is complete. We’ll also be on hand for any aftercare to ensure you’re pleased with your new space.
04
Types of Loft Conversions
Every property in London is unique, and so are the goals of each homeowner. That’s why at New Build Contractors we offer a full range of loft conversion styles, each designed to make the most of your home and blend in with its existing architecture.
Dormer Loft Conversion
Dormers are the most common type of loft conversion in London, and for good reason. By extending vertically from the existing slope of your roof, a dormer creates extra headroom, natural light and usable floor space. This makes dormers perfect for transforming cramped attic spaces into full-size bedrooms, en-suite bathrooms, or home offices. They suit all types of properties from Victorian terraces to modern townhouses and are a cost-effective way to add loads of space without altering the footprint of your home.
L-Shaped Dormer Conversion
L-shaped dormers are particularly suited to London’s Victorian and Edwardian homes, which often have a rear addition. By combining two dormers at right angles, you get an ample L-shaped space that can usually accommodate multiple rooms. Many families choose this option to create a spacious master suite with an en-suite bathroom and dressing area or two children’s bedrooms with a shared bathroom. It’s a clever way to make the most of period layouts whilst modernising your living space.
Hip-to-Gable Conversion
For homes with a hipped roof in London, such as the semi-detached or end-of-terrace properties, much of the loft space can feel unusable due to sloping walls. A hip-to-gable conversion in London resolves this by extending the sloping side (“hip”) into a vertical gable wall. This structural change provides you with more internal volume and flexibility for larger bedrooms, playrooms, or even an additional bathroom. Hip-to-gable conversions are often combined with rear dormers for even more space and light.
Mansard Conversion
Mansard conversions are the most extensive and often the most striking type of loft conversion. They involve rebuilding one or both sides of the roof to create a flat roof with steeply sloping walls, usually at a 70° angle. This transforms your loft into a new, full-height floor of your home, providing the most usable living space. Mansards are particularly popular in central London, where space is at a premium, and are often approved in conservation areas due to their traditional design. They are ideal if you want to add multiple bedrooms, bathrooms or even a self-contained studio.
Velux / Rooflight Conversion
A Velux (or rooflight) conversion is the simplest and most cost-effective way to turn your loft into a usable space. Instead of altering the roof shape, we install high-quality roof windows directly into the existing slope. This floods the space with natural light and ventilation, making it perfect for a home office, guest bedroom, or hobby room. Velux conversions require sufficient head height to be practical, but they involve minimal structural work, shorter build times, and lower costs than other options.
Loft Pods & Roof Terraces
For homeowners seeking something unique, loft pods and roof terraces provide modern alternatives.
Loft pods are small extensions that add compact spaces, such as a study, nursery, or guest room. They’re a clever way to gain an extra room without committing to a full-scale conversion.
Roof terraces turn your loft into both an indoor and outdoor living area. With sliding doors opening onto a private terrace, you can enjoy city views, garden space or even a rooftop retreat in the heart of London.
We specialize in modular design systems, front-end development, and intuitive interfaces. Our strength lies in crafting elegant, minimal solutions — in both design and code. We believe the best collaborations are those where curiosity leads to learning and growth. As a team of passionate problem-solvers, we love working with visionary brands who aim to inspire.
| Loft Conversion Type | Best For | Main Benefits | Planning Notes | Typical Cost (London) | Typical Duration |
|---|---|---|---|---|---|
| Dormer | Most terraces & semis; adding a full-height bedroom or en-suite | More headroom & floorspace; good daylight; strong value uplift | Often under Permitted Development (PD) if within volume limits | £45,000–£70,000+ | 10–14 weeks |
| L-Shaped Dormer | Victorian/Edwardian homes with rear addition | Maximises footprint; can fit multiple rooms or a master suite | May need planning depending on size/position; check PD limits | £55,000–£85,000+ | 12–16 weeks |
| Hip-to-Gable | Semi-detached & end-of-terrace with hipped roofs | Turns sloped side into usable space; often paired with dormer | Sometimes PD; structural changes require engineer sign-off | £55,000–£80,000+ | 12–16 weeks |
| Mansard | Maximising space; central London & period streets | Creates near full new storey; best for multiple rooms | Usually requires planning; conservation areas often prefer it | £65,000–£100,000+ | 14–20 weeks |
| Velux / Rooflight | Good existing head height; quickest & most cost-effective | Minimal structural work; fastest build; excellent daylight | Commonly PD; building regs always apply (fire, stairs, insulation) | £30,000–£45,000+ | 6–10 weeks |
| Loft Pods & Roof Terraces | Compact extra room or indoor-outdoor living | Flexible layouts; potential outdoor amenity space | Planning likely for terraces; structural & waterproofing critical | £35,000–£70,000+ (pod) / varies (terrace) | 8–14 weeks |
Notes: Costs and timelines are indicative for London and depend on size, structure, finishes, and approvals. Building Regulations apply to all conversions. Party Wall Agreements may be required for terraced/semi-detached properties.
Planning Permission & Regulations in London
One of the first questions we get asked is: “Do I need planning permission for my loft conversion?” The answer depends on the type of property you own, the size of your project and where in London you live. Regulations vary between boroughs, and some areas, such as Hampstead, Richmond, and Kensington, have stricter rules than others. At New Build Contractors, we manage the entire process and ensure your project is compliant before work commences.
Permitted Development (PD)
Many loft conversions can be done under Permitted Development, which means you don’t need full planning permission. This covers:
Velux/rooflight conversions where no major structural changes are made.
Dormer conversions within certain size limits (generally up to 40m³ for terraced houses or 50m³ for detached/semi-detached).
Extensions that don’t exceed the highest part of the existing roof.
But PD doesn’t apply to flats or maisonettes and can be restricted if your home is in a conservation area or is a listed building.
Planning Permission
If your project goes beyond PD, then you’ll need planning approval from your local borough. This is usually the case for:
Mansard conversions – these involve a significant alteration to the roof and almost always require full planning permission.
Large dormers or L-shaped conversions that exceed PD volume allowances.
Properties in conservation areas or heritage zones where design must respect the character of the street.
We prepare and submit all drawings, statements and applications on your behalf and work with the local planning authority until approval is granted.
Party Wall Agreements
For terraced and semi-detached homes – which make up a large part of London’s housing stock – a Party Wall Agreement is often required. This legal document informs your neighbours about the works and obtains their agreement to any alterations to the shared wall. We guide you through the process and, if necessary, appoint surveyors to ensure everything is official. Clear communication with neighbours prevents disputes and keeps your project on track.
Building Regulations
Regardless of whether planning permission is needed, Building Regulations approval is always required. This covers:
Structural safety – ensuring the roof can withstand the new loads.* Staircases & access – safe and compliant access to your loft.
Fire Safety – Escape Routes, Fire Doors, and Smoke Alarms.
Insulation & energy efficiency – meets modern standards for comfort and performance.
Soundproofing – important in London’s terraced and semi-detached homes.
We work closely with building control to ensure that all works meet the required standards, and we conduct regular inspections throughout the build.
Our Role
From submitting planning applications to arranging party wall notices, we take the stress off your shoulders. London regulations can be complex, but we’ve worked with councils across the city and are familiar with the expectations of each authority. This means faster approvals, fewer delays, and complete compliance for your peace of mind.
| Scenario | Planning Permission | Party Wall Notice | Building Regulations | Notes (London-specific) |
|---|---|---|---|---|
| Velux / Rooflight conversion (no roof shape change) | No* | Often | Yes | Usually under Permitted Development (PD). Flats/maisonettes excluded; CA/listed may restrict. |
| Dormer within PD volume limits (no roof higher than ridge) | No* | Likely | Yes | PD limits: ~40m³ (terrace) / ~50m³ (semi/detached). Materials to be similar; rear/side only. |
| L-shaped dormer (Victorian/Edwardian rear addition) | Sometimes | Likely | Yes | May exceed PD in volume/position; boroughs vary. Check early. |
| Hip-to-gable (semi / end terrace) | Sometimes | Likely | Yes | Can be PD if within volume & not fronting a highway; engineer sign-off required. |
| Mansard conversion (full roof remodel) | Yes | Likely | Yes | Almost always needs planning; often preferred form in central London conservation areas. |
| Loft pod / Roof terrace | Yes | Likely | Yes | Terraces rarely PD; privacy/overlooking assessed closely by London boroughs. |
| Flats & maisonettes (any loft works) | Usually | Often | Yes | No PD rights; freeholder consent & lease review required; expect planning. |
| Conservation area / Listed building | Usually | Likely | Yes | Design & materials scrutinised; listed buildings need Listed Building Consent. |
*“No” under Planning Permission usually means your project is likely under Permitted Development (PD). Building Regulations approval is required for all loft conversions. Party Wall Notices are commonly needed for terraced and semi-detached homes.
Past Works
Case Studies
The Types of Properties we work on
London’s housing is as varied as its people, and no two loft conversions are the same. Over the years, we have worked on properties of every shape, size and era, adapting designs to make the most of each home.
Victorian & Edwardian Terraces
These are the most common types of property in London and offer great opportunities for loft conversions. Dormer and L-shaped dormer designs are particularly popular, as they create large bedrooms, bathrooms, or even multiple rooms in the roof space. With their rear additions and narrow plots, we know how to maximise light and space without losing the period charm.
1920s & 1930s Houses
Semi-detached and terraced homes from this era often have hipped roofs, making them perfect for hip-to-gable conversions. By extending the roof to a whole gable wall, we can release a surprising amount of space, often enough for a large master suite or two new bedrooms with a shared bathroom.
Semi-Detached & Detached Homes
These properties offer us the flexibility for almost any type of conversion, from simple Velux upgrades to complete mansard rebuilds. With more roof space to work with and fewer shared walls, detached homes in particular allow for bold design choices, such as roof terraces, loft pods, or bespoke glazing features.
Flats & Maisonettes
Loft conversions in flats and maisonettes can be more complex but are still very achievable with careful planning. We handle the extra steps, such as freeholder consent, leasehold checks, and party wall agreements, to ensure everything runs smoothly. Many of our clients in London have gained valuable living space in their top-floor flats by adding bedrooms or home offices through Velux or dormer conversions.
Conservation Areas & Listed Buildings
Homes in conservation areas or with listed status require sensitive design and stricter planning rules. We have experience working with local planning authorities across London to ensure conversions respect the character of these properties while still creating beautiful, functional spaces. Whether it’s a discreet Velux conversion or a carefully detailed mansard, we strike a balance between heritage and modern living needs.
See what our customers have to say about us
We’ve partnered with New Build Contractors on several design-and-build projects across London and have always found them highly professional and dependable. They play an integral role in our pre-construction planning, bringing valuable input on design, budgeting, and tendering for both current and upcoming projects. What stands out most is their open and honest way of working. Communication is always clear, and their management structure keeps everything well organised and transparent. Their teams are focused, flexible, and committed to delivering quality on-site. That collaborative, can-do attitude makes working with them such a positive experience.
We've worked closely with New-Build Contractors on a range of new build residential projects, from mixed-use flats in London to multi-million-pound homes in Berkshire.. Their team has consistently delivered high-quality results. Their residential construction experience shows they understand how to approach each project with utmost professionalism and attention to detail.
The effort and professionalism shown by the team at New Build Contractors throughout the project were outstanding. They remained focused, reliable, and solution-driven even during the most demanding phases and in a challenging site location. Their conduct on site was exemplary, and the client’s feedback has been overwhelmingly positive. The result speaks for itself: a high-quality finish that reflects the hard work and commitment of everyone involved.
Loft Conversion Design Ideas
One of the best things about a loft conversion is its versatility. Whether you live in a Victorian terraced house in Clapham, a 1930s semi in Ealing or a modern townhouse in Canary Wharf, your loft can be turned into almost any type of space to suit your lifestyle, family needs and the character of your property.
Master Bedroom with En-Suite
A popular choice for Londoners is to turn the loft into a master bedroom. By creating a bedroom with an en-suite bathroom, you can enjoy a peaceful retreat at the top of the house, away from the busier areas below. Skylights or dormer windows flood the room with natural light, and clever storage solutions make the most of the sloping ceilings. In regions like Wimbledon or Hampstead, where space is at a premium, a master suite loft conversion can also add value to your home.
Home Office or Creative Studio
With remote and hybrid working now the norm across London, many homeowners are choosing to convert their lofts into offices or studios. A loft office offers privacy, natural light and a quiet space for productivity, perfect for professionals in Canary Wharf, creatives in Shoreditch or anyone who needs to focus away from the rest of the household. We can design bespoke built-in desks, soundproofing and storage to create a space that works as hard as you do.
Children’s Bedrooms or Playrooms
Families across London often outgrow their homes, particularly in areas where upgrading to a larger home is expensive. A loft conversion can free up space by creating bedrooms or playrooms for children. Dormer and L-shaped conversions are especially suitable for this, providing sufficient height and floor space for growing families in areas such as Balham, Dulwich, and the North London suburbs.
Guest Accommodation
If you regularly host friends or family, a loft conversion can provide a comfortable guest suite with its own bathroom. This is particularly appealing in central London, where space is at a premium. A well-designed guest loft not only makes visitors feel welcome but also ensures they have the privacy and independence they need during their stay.
Living Spaces & Entertainment Rooms
Some homeowners prefer to utilise their loft conversion as a versatile living space, whether that’s a second lounge, a cinema room, or even a games room. With the creative use of natural light and clever layouts, we can design spaces that are perfect for entertaining. For homes in West London with garden views, Juliet balconies or large dormer windows can create a seamless connection between indoors and outdoors.
Special Features & Design Elements
The success of a loft conversion is often in the details. We design for London properties:
Skylights & roof windows – to bring as much natural light as possible into tight terraced homes.
Juliet balconies & French doors – to bring in light and fresh air, especially in areas like Richmond or Chiswick, where the views are stunning.
Bespoke storage – fitted wardrobes and under-eaves cupboards to maximise every inch.
Bathrooms in the loft – from compact en-suites to full spa-style retreats.
Energy-efficient finishes – essential in London to reduce bills and improve comfort.
What to consider when planning for a Loft Conversion?
| Issue | What It Means for Your Loft Conversion |
|---|---|
| Roof Spread | If the loft isn’t converted properly, the roof can gradually spread apart. This problem may not appear for months or even years, and fixing it can end up costing more than the original conversion. |
| Leaks & Moisture | Poor insulation or ventilation in a loft can lead to condensation, damp, or even rot. Left unchecked, these issues can weaken the structure and increase the risk of fire. |
| Planning & Structural Support | A loft conversion adds weight and extra forces to your property. Careful structural planning is essential to ensure your home can safely support the new space. |
| Ceiling Ties & Stair Placement | Creating space for a staircase is one of the most common challenges. Ceiling ties and headroom need to be factored in to design safe, practical access. |
| Roofing Materials | The type of roofing materials used will affect cost, appearance, and even resale value. Choosing the right materials also helps ensure long-term durability. |
The Next Space is Yours
Let’s Design What’s Next
— Address
71-75 Shelton Street Covent Garden London WC2H 9JQ
— Hours
Mon-Fri: 9 AM to 5 PM
Sun: Closed