
Rear Extension Drawings in Barnsbury N1
Fixed-fee, MCIAT-chartered rear extension drawings for Barnsbury (N1) homeowners — London Borough of Islington validation and local constraints handled from the start.
Barnsbury (N1) is Georgian and early-Victorian terraces and garden squares, much of it in flats, so typical work spans rear and closet-wing extensions, basement and lower-ground projects, and internal reconfigurations that respect the historic plan form.
As one of Islington's most tightly conserved areas, Barnsbury demands careful treatment of frontages, railings, rooflines and rear elevations — we match the period detail and prepare the heritage and design justification Islington Council expects, mindful of the Regent's Canal setting nearby.


Planning in Barnsbury (N1): what to know before you apply
No published householder Article 4 direction is relied upon here, but the Barnsbury conservation area imposes rigorous control of frontages, rear closet wings and basement excavation; flat subdivision and neighbour amenity further constrain rear and lower-ground works.
Typical Barnsbury housing stock
Elegant Georgian and early-Victorian terraces and garden squares — around Gibson Square and the surrounding streets — many subdivided into flats and maisonettes. Original closet wings, lightwells and long rear gardens shape the scope for extensions and basement projects.
Streets we regularly draw for in Barnsbury
Gibson Square · Cross Street · Barnsbury Street · Offord Road
Rear Extension Drawings for Barnsbury (N1) homes: the package and the process
Every rear extension drawings we prepare for an Barnsbury property is drawn to London Borough of Islington’s validation standards and tuned to the N1 constraints above. Here is what the drawing package covers and how the process runs from first survey to approval.
A single-storey rear extension is the most common way London homeowners add space, usually taking the form of an open-plan kitchen-diner that opens onto the garden through bi-fold or sliding doors, with rooflights or a roof lantern bringing daylight deep into the plan. Because depth and height are tightly controlled by permitted development rules and by the 45-degree rule that protects neighbouring windows, the design work sits as much in checking what the council will allow as in drawing what you want.
DrawingsDirect draws rear extensions for permitted development, the larger home extension prior-approval scheme and full householder planning, with structural calculations for the opening and roof produced in-house by our MCIAT-chartered team. If your project also involves widening the kitchen sideways or adding a second storey, see our Side Return, Wraparound and Double Storey Extension pages — many London rear extensions grow into one of those during design.
Do I need planning permission for a rear extension in London?
Many single-storey rear extensions qualify as permitted development, meaning no planning application is needed, provided depth, height and materials stay within set limits. That changes if your property sits in a conservation area or is subject to an Article 4 direction, both of which can remove permitted development rights across a street or borough — in that case a full householder planning application is required regardless of size.
Even where an extension qualifies, most homeowners obtain a Lawful Development Certificate to confirm that status in writing before building — useful for mortgage lenders, buyers and Building Control. We check your property against your borough's constraints before recommending a route.
How deep can a single-storey rear extension go?
Depth is the main constraint on a rear extension, and it depends on your house type and whether you use standard permitted development or the larger home extension scheme.
Permitted development
Standard permitted development allows a single-storey rear extension up to 3 metres deep for terraced and semi-detached houses, or 4 metres for detached houses, generally with eaves height limited to match or stay close to the existing house.
Larger home extension scheme
The prior-approval scheme extends this to 6 metres for terraced and semi-detached houses and 8 metres for detached houses. Your council writes to affected neighbours; if none object within the notification period, approval follows without a full planning application. If an objection is raised, the council assesses the impact on neighbouring light and outlook itself, rather than automatically refusing, so a well-considered design still has a good chance of approval.
| Route | When it applies | Typical fee |
|---|---|---|
| Permitted development (Lawful Development Certificate) | Depth within 3m (terraced/semi) or 4m (detached), height and materials within PD limits | PD/LDC pack ~£950–£1,450 |
| Larger home extension (prior approval) | Depth up to 6m (terraced/semi) or 8m (detached), with neighbour notification | from £1,100 |
| Full householder planning permission | Extension exceeds PD/larger-home limits, or the property is in a conservation area with an Article 4 direction | Full Planning pack ~£1,600–£2,400 |
| Planning + Building Regulations (structural) | Combined planning and construction-ready pack with structural calculations for the opening and roof | Planning + Building Regs pack ~£2,200–£3,850 |
Rear Extension Drawings in Barnsbury N1 — FAQs
How much does a rear extension cost to design in London?+
Do I need an architect for a rear extension?+
How long does it take to get rear extension drawings?+
What is the 45-degree rule?+
Will I need a Party Wall Agreement for a rear extension?+
Do I need planning permission for an extension or loft in Islington?+
My Islington property is a converted flat — can I still extend?+
How does Islington's tight plot size affect what I can build?+
How long does Islington Council take to decide?+
How much do planning drawings cost in Islington?+
Get your free Barnsbury planning assessment
Tell us your Barnsbury (N1) address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.