Architects in Barnet for Extensions, Loft Conversions & Planning
From planning applications to structural design — we help Barnet homeowners extend, convert and improve their homes.
Architectural Services in Barnet
Barnet is one of London’s largest boroughs, stretching from the leafy suburbs of Totteridge and Mill Hill to the Victorian terraces of East Finchley and Friern Barnet. With a housing stock ranging from characterful 1930s semi-detached homes to Edwardian villas and post-war estates, homeowners across the borough regularly look to extend and convert their properties rather than face the cost and disruption of moving.
Whether you are planning a house extension in Barnet to create an open-plan kitchen-diner, a kitchen extension in Barnet to transform your ground floor, a loft conversion to add a bedroom or home office, or a full two-storey extension on a detached property, getting the architectural design right from the start is essential. Many parts of Barnet fall within conservation areas or are subject to specific planning constraints that require careful, experience-led design work.
We provide full architectural drawing packages, handle your planning permission application and deliver the building regulation documents your contractor needs to build with confidence. Every project begins with a detailed 3D measured survey and ends with a set of drawings tailored to your property and your ambitions. We also provide in-house structural engineering in Barnet, delivering beam calculations and structural designs so you deal with one team — your Barnet architects — from concept to completion. We also serve homeowners across neighbouring boroughs — see our pages for architects in Ealing, architects in Wandsworth, architects in Wimbledon, architects in Fulham and architects in Richmond.
Why Barnet Projects Need Careful Planning
Barnet is one of London’s largest boroughs by area, stretching from Hampstead Garden Suburb in the south to the Hertfordshire border. The borough contains significant Green Belt land and over 15 conservation areas in Barnet including Monken Hadley, Totteridge Village, Mill Hill, Church End Finchley and Hampstead Garden Suburb — each with strict controls on alterations and extensions.
Many properties across Barnet are 1930s semi-detached homes, ideally suited to rear extensions, loft conversions and side returns. However, Article 4 directions in several conservation areas remove permitted development rights, meaning even modest changes may need planning permission in Barnet from the council.
We prepare applications that address Barnet Council’s residential design guidance SPD, covering everything from roof form and materials to the impact on neighbouring properties. Our architects handle full planning submissions, lawful development certificates and appeals — working with Barnet’s planning officers to keep your project on track — whether it involves a house extension in Barnet, a loft conversion in Barnet or a rear extension in Barnet.
What We Design
Rear Extension
Open-plan kitchen-diners, garden rooms and ground-floor living spaces designed around your lifestyle.
Learn More →Loft Conversion
Dormers, hip-to-gables and roof extensions across Barnet — adding bedrooms, offices and bathrooms.
Learn More →House Extension
Side returns, single-storey and multi-room layouts to transform your existing footprint.
Learn More →Wraparound Extension
Rear and side combined for maximum internal space — ideal for open-plan kitchens and family rooms.
Learn More →Double Storey Extension
Two-floor extensions for growing families — maximising space from your available footprint.
Learn More →Planning Applications
Full householder applications, lawful development certificates and appeals — submitted to Barnet Council on your behalf.
Learn More →Building Regulation Drawings
Detailed technical drawings for Building Control sign-off, covering structure, insulation, drainage and fire safety.
Learn More →Structural Design
Beam calculations, steelwork specifications and structural engineering — all handled in-house by our team.
Learn More →Our Featured Works
Loft Conversions and Dormer Designs in Barnet
A loft conversion in Barnet is one of the most popular home improvements across the London Borough. The borough’s large stock of 1930s semi-detached homes — found in areas like Hendon, Whetstone and Edgware — are particularly well suited to hip-to-gable and rear dormer conversions, which can add a full-sized bedroom, bathroom or home office without reducing garden space.
For properties with hipped roofs, a hip-to-gable conversion extends the side wall to create a vertical gable end, unlocking significantly more usable floor area than a dormer alone. Combined with a rear box dormer, this approach maximises the loft space while keeping the front roofline unchanged — an important consideration for both planning and streetscape character.
As specialist loft conversion architects in Barnet, we know that most rear dormer conversions fall within permitted development in Barnet rights, meaning no formal planning application is required. However, properties in conservation areas such as Monken Hadley, Totteridge and Mill Hill Village may face additional restrictions. We assess your property’s specific planning status before starting any design work and handle all necessary applications.
Period Home Extensions in Barnet
Side Return Extensions
Reclaiming the narrow side passage on Victorian terraces in East Finchley and Friern Barnet to create wider, open-plan ground floor living spaces.
Rear Extensions on 1930s Semis
Single and double storey rear extensions on the classic semi-detached homes found across Hendon, Edgware and Whetstone, with bifold doors opening onto the garden.
Wraparound Extensions
Combining side and rear extensions to maximise ground floor area on corner plots and wider-fronted properties throughout the borough.
Hip-to-Gable Loft Conversions
Converting hipped roofs to gable ends on 1930s and Edwardian semis to unlock full-width loft space for a new bedroom or bathroom.
Double Storey Extensions
Adding ground and first floor space simultaneously, a popular option on detached and semi-detached properties in Mill Hill and Totteridge.
Garage Conversions
Converting attached or integral garages into habitable rooms — a cost-effective way to add a reception room, utility or ground floor bedroom.
Planning Permission Support in Barnet
Barnet Council oversees planning applications across one of London’s most varied boroughs. With approximately 20 designated conservation areas — including Monken Hadley, Totteridge Village and Mill Hill — many properties face additional restrictions on what can be built without formal planning approval. Even outside conservation areas, the council expects proposals to respect the character of the street and the scale of neighbouring buildings.
For extensions and loft conversions, the council pays close attention to the impact on neighbours’ daylight, privacy and outlook. Rear dormers, while often permitted development, must comply with specific size and material requirements. Double storey extensions and side extensions require particularly careful design to avoid overbearing impacts or an unbalanced streetscape.
We prepare all planning drawings, design and access statements and supporting documents required for a householder planning application to Barnet Council. Where your project falls within permitted development, we prepare lawful development certificates to give you and your contractor formal confirmation that the works are compliant. Whether you need a design and build service in Barnet or drawings for a new build in Barnet, our architects manage the process from start to finish.
Our Barnet Design and Planning Process
Your 3D Site Survey
An appointed surveyor will carry out a full measured survey of your property, noting down all your desired requirements for your proposal.
Drawings Initiated
Your project is allocated to one of our architectural designers who will design it from the ground up, taking into account all your needs.
You Review It
Your first draft is typically ready in 7 working days, and within 10 at the latest. Review the designs, send us any changes, and we’ll finalise your drawings for submission.
Submission & Decision
Your plans will be submitted strategically for swift council approval. Expect a decision in 6–8 weeks. We handle any required changes for free.
Technical Design
Once plans are approved, our Structural Engineers and Architects will manage the Structural Design and Building Regulations compliance. You can also get construction quotes from us to compare.
Construction
If you decide to build with us, we arrange a detailed consultation to finalise your requirements and ensure everything aligns perfectly with your vision.
Ready to start your project?
Get a Free ConsultationWhy Barnet Homeowners Choose Salstan
Barnet Planning Knowledge
We work extensively across the London Borough of Barnet, understanding conservation areas in Monken Hadley and Totteridge, and the council's design expectations for the borough's varied housing stock.
Structural Design In-House
No need to hire a separate structural engineer. We handle beam calculations, steelwork and load-bearing assessments internally.
Fixed-Fee Pricing
Clear pricing from the start with no hidden costs or hourly surprises. You know exactly what you are paying for.
Construction Services
From design through to build — our in-house construction team delivers your project without the need for a separate contractor.
3D Visuals Included
See your extension or loft conversion in 3D before a single brick is laid. Included in every design package.
One Point of Contact
A dedicated designer manages your Barnet project from start to finish, so nothing falls through the cracks.
How Much Does an Extension or Loft Conversion Cost in Barnet?
We believe in transparent pricing from the start. Below are our starting prices for the most common Barnet extension and loft conversion projects. Your final fixed-fee quote is confirmed after we understand your property, scope and council requirements.
- Full 3D measured survey
- Architectural drawings
- Unlimited revisions
- Planning submission
- Full 3D measured survey
- Architectural drawings
- Unlimited revisions
- Planning submission
- Full 3D measured survey
- Architectural drawings
- Unlimited revisions
- Planning submission
Your final price depends on property size, planning route, conservation area status and structural complexity. We discuss all of this during your free initial consultation before you commit to anything.
Areas We Cover in Barnet Borough
Victorian and Edwardian properties sit alongside the Green Belt at the borough's northern edge. Monken Hadley conservation area has strict controls on roof alterations and front elevations, while properties along the High Street and surrounding roads offer strong potential for rear extensions and loft conversions with careful design.
North Finchley, East Finchley and Church End each have distinct character, from 1930s semis to Edwardian terraces. Church End Finchley conservation area requires sensitive design, but the wider Finchley area is well suited to single and double storey rear extensions, garage conversions and hip-to-gable lofts.
A mix of inter-war semis, post-war estates and some larger detached properties in the NW4 area. Hendon offers excellent scope for rear extensions, side returns and loft conversions. Properties near the Welsh Harp reservoir may face additional ecological considerations during planning.
Mill Hill retains a village character with its conservation area centred around The Ridgeway. Larger detached properties and period homes make it popular for substantial extensions and full refurbishments. We design schemes that respect Mill Hill's character while maximising the potential of each site.
Predominantly 1930s semi-detached housing stock in the HA8 area, making Edgware ideal for rear and side extensions, loft conversions and full home renovations. Permitted development rights are generally available here, allowing many projects to proceed without a full planning application.
Totteridge Village is one of Barnet's most prestigious conservation areas, with large detached properties set on generous plots. Planning applications here require careful attention to the rural village character. Whetstone offers more varied housing with good extension potential along the main corridors.
A mix of Victorian terraces near the station and inter-war housing further out. East Barnet village has its own conservation area with design sensitivities around the church and green. Both areas are popular for kitchen-diners, loft bedrooms and wraparound extensions.
Frequently Asked Questions About Architects in Barnet
We are here to help with your Barnet extension, loft conversion or planning query.
- Free initial consultation
- Barnet Council planning experts
- In-house structural engineers
- Fixed-fee pricing guarantee
It depends on the size and position of the extension and your property's location. Many single-storey rear extensions fall under permitted development, but properties in conservation areas such as Monken Hadley or Totteridge may need full planning permission. We check your property's specific planning status before starting any design work.
As a guide, construction costs for a single-storey rear extension typically sit around £2,000–£3,000 per square metre, plus professional fees for architectural drawings, structural engineering and the planning application. Costs vary depending on specification, access and ground conditions. We provide clearer estimates once we have surveyed your property.
Yes. The 1930s semi-detached homes common across Hendon, Whetstone and Edgware are well suited to loft conversions. A hip-to-gable conversion combined with a rear dormer typically creates the most usable space, adding a full bedroom and bathroom without reducing your garden.
A dormer extends outward from the rear roof slope to add headroom and floor area. A hip-to-gable conversion changes the side roof from a sloped hip to a vertical gable wall, widening the entire loft. On hipped-roof properties, combining both approaches maximises the space available.
Yes. We have structural engineering capability in-house, so we handle beam calculations, steelwork specifications and foundation design without you needing to hire a separate structural engineer. This saves time and avoids coordination delays.
From initial consultation to a planning decision, the process typically takes 10 to 14 weeks. This includes the survey, design development, drawing preparation and the statutory planning determination period. Permitted development projects are usually faster.
Yes, but the range of works you can carry out under permitted development may be restricted. Extensions in conservation areas such as Monken Hadley, Totteridge and Mill Hill often require a full planning application. We design proposals that respect the conservation area character while meeting your space requirements.
If your extension involves building on or near a shared boundary wall, or excavating within certain distances of a neighbouring foundation, the Party Wall Act applies. You must serve formal notice on your neighbours before work begins. We advise on whether a party wall agreement is needed and can recommend experienced surveyors.
Building regulations drawings cover structural design, insulation, drainage, ventilation and fire safety. They are required for Building Control sign-off before construction can begin. We produce these as part of our standard service, alongside planning drawings.
Yes. We regularly take on projects where a previous application has been refused. We review the decision notice, identify the specific reasons for refusal and redesign the scheme to address those issues while still meeting your brief.
Yes. Beyond architectural drawings and planning, our in-house construction team can build your project too. This means one team manages the entire process from initial survey through to completion, with no gaps between design intent and what gets built.
Ready to Start Your Barnet Project?
Book a free consultation and let us show you what is possible with your home.
Our Portfolio
Rainham, London
Rear Extension
Single-storey rear extension with bi-fold doors and contemporary kitchen design.
Gerrards Cross
Rear Extension
Elegant rear extensions with big bifold doors, apex windows and skylights, flooding the space with maximum natural light.
Ilford, London
rear Extension
Modern rear wraparound extension to a victorian property creating seamless indoor-outdoor living with floor-to-ceiling glazing.
Croydon, London
Wraparound Extension
L-shaped wraparound extension maximising ground floor living and dining space. On this project we actually completed the loft dormer extension, double storey side and partial first floor rear extensions too!
Kensal Rise, London
Wraparound Extension
Side and rear wraparound extension with modern kitchen and open-plan family area. Featuring big crittal doors and large skylights on the sloping roof.
Wandsworth, London
Wraparound Extension
Full wraparound extension with panoramic glazing and premium specification. Can you spot the overall balance with the L-shape loft dormer extension we also designed for this client?
Bromley, London
Double Storey Extension
Two-storey side extension with matching brickwork, extra bedrooms and bathrooms. In fact we also re-designed the entire loft space and had major approvals for an approx 6m by 14m ground floor wraparound extension!
Windsor
Double Storey Extension
Grand double-storey rear extension with integrated garage and a full internal remodel of the entire home.
Richmond, London
DOUBLE STOREY EXTENSION
Grand double storey rear extension with open-plan kitchen-diner and master suite above.
Merton, London
Loft Conversion
Hip-to-gable dormer loft conversion/extension to accomodate a master suite with a walk-in wardrobe and a modern ensuite.
Purley, London
Loft Conversion
Front cottage dormers and a large rear box dormer extension/conversion with Juliet balcony and vaulted ceiling bedrooms. This was pure luxury.
Thames Ditton, Surrey
Loft Conversion
Hip-to-gable loft dormer conversion/extension with premium finish. We had to design something different as opposed to the standard dormer extension so it can blend in with the rest of the extensions we designed for this house.
East London
Flat Conversion
Victorian end of terrace mixed use properties converted into a luxury two-bedroom flats with modern amenities.
Crystal Palace, London
Flat Conversion
Property subdivisions into modern self-contained apartments.
Barnet, London
Flat Conversion
Full house-to-flats conversion with multiple large extensions and comprehensive planning and building regulations approval.
Wembley, London
New Build
Contemporary new-build family homes with open-plan living and sustainable design features.
Surrey
New Build
Bespoke new-build bungalow development designed from foundation to completion.
Harrow, London
New Build
Multi-unit new-build project with distinctive architectural detailing and landscaping.
