
Rear Extension Drawings in Elm Park RM12
Fixed-fee, MCIAT-chartered rear extension drawings for Elm Park (RM12) homeowners — London Borough of Havering validation and local constraints handled from the start.
Elm Park in RM12 is one of London's clearest interwar planned suburbs, a 1930s Homesteads-style estate of near-identical semi-detached houses around Elm Park station. The vast majority of our projects here are single-storey rear extensions, loft conversions and hip-to-gable roof works on family semis that typically sit within permitted development.
Because the estate is so visually uniform, London Borough of Havering pays attention to how additions read against matching neighbours, so we detail extensions and dormers to preserve the rhythm of the street while keeping householder schemes fast to approve.


Planning in Elm Park (RM12): what to know before you apply
No published householder Article 4 direction covers Elm Park; the main sensitivity is the estate's uniform interwar character, with the RAF Hornchurch conservation area on the fringe. Most semis retain full permitted development rights for rear and roof works.
Typical Elm Park housing stock
Elm Park is a planned 1930s Homesteads-style estate of highly uniform interwar semi-detached houses laid out around the station and The Broadway. Consistent bays, hipped roofs and matching frontages mean rear and roof extensions are the mainstay, with design continuity across neighbouring pairs a recurring theme.
Streets we regularly draw for in Elm Park
Elm Park Avenue · Abbs Cross Lane · Calbourne Avenue · Rosewood Avenue
Rear Extension Drawings for Elm Park (RM12) homes: the package and the process
Every rear extension drawings we prepare for an Elm Park property is drawn to London Borough of Havering’s validation standards and tuned to the RM12 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 Elm Park RM12 — 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 Havering?+
How does green-belt land affect my Havering project?+
Can I build a bigger extension because Havering plots are larger?+
How long does Havering Council take to decide?+
How much do planning drawings cost in Havering?+
Get your free Elm Park planning assessment
Tell us your Elm Park (RM12) address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.