
Rear Extension Drawings in Bermondsey SE1
Fixed-fee, MCIAT-chartered rear extension drawings for Bermondsey (SE1) homeowners — London Borough of Southwark validation and local constraints handled from the start.
Bermondsey (SE1) is a dense pocket of Southwark where Georgian townhouses, former tanneries and warehouse conversions sit on a surviving medieval street grid — so homeowner work here leans toward loft conversions, roof terraces and shallow rear or side-return extensions that respect the narrow historic plots.
Most of the residential fabric lies within the Bermondsey Street or Tower Bridge Conservation Areas, where roof, front and rear alterations are judged against the historic townscape. We confirm which conservation-area boundary applies before advising whether your scheme is permitted development or needs a full householder application.


Planning in Bermondsey (SE1): what to know before you apply
Homes across this part of SE1 typically sit within the Bermondsey Street or Tower Bridge Conservation Areas, which curtail permitted-development rights and mean many roof and side changes need a householder application. Southwark's Article 4 directions here concern use changes rather than extensions, so the conservation-area appraisal is the main early check.
Typical Bermondsey housing stock
Georgian and early-Victorian townhouses and shop-houses line Bermondsey Street on a medieval plot pattern, interleaved with converted tanneries and warehouses. Narrow frontages, arched alleyways to rear yards and shallow back plots define what can be added.
Streets we regularly draw for in Bermondsey
Bermondsey Street · Tanner Street · Morocco Street · Leathermarket Street
Rear Extension Drawings for Bermondsey (SE1) homes: the package and the process
Every rear extension drawings we prepare for an Bermondsey property is drawn to London Borough of Southwark’s validation standards and tuned to the SE1 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 Bermondsey SE1 — 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 in Southwark?+
What is the Dulwich Estate scheme of management?+
Can you handle a warehouse or riverside conversion in Bermondsey or Bankside?+
How long does Southwark Council take to decide?+
How much do planning drawings cost in Southwark?+
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Tell us your Bermondsey (SE1) address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.