
Wraparound Extension Drawings in Osterley TW7
Fixed-fee, MCIAT-chartered wraparound extension drawings for Osterley (TW7) homeowners — London Borough of Hounslow validation and local constraints handled from the start.
Osterley is a green, spacious interwar suburb wrapped around Osterley Park, so the houses here are larger than the west-Hounslow average and the projects follow suit: wide rear extensions, two-storey side additions and generous loft conversions on the semis and detached homes along Jersey Road and Ellington Road. Bigger footprints mean many schemes go past permitted-development volume and land as full householder applications.
Because so much of the district sits within or beside the Osterley Park and Spring Grove conservation areas — and under mature, often protected street trees — we design to Hounslow Council's higher bar here, keeping the scale subordinate, matching brick and fenestration, and coordinating with an arboricultural approach where roots and TPOs affect the foundations.


Planning in Osterley (TW7): what to know before you apply
No published householder Article 4 direction applies in Osterley, but the Osterley Park and Spring Grove conservation areas, the National Trust parkland setting and Tree Preservation Orders on mature street trees all tighten how extension scale, materials and foundations are assessed.
Typical Osterley housing stock
Osterley is a leafy 1920s and 30s suburb of substantial semi-detached and detached houses on generous, tree-lined plots around Osterley Park. Roads like Jersey Road and Ellington Road carry larger family homes that suit full-width rear extensions, two-storey side additions and considered loft conversions.
Streets we regularly draw for in Osterley
Ellington Road · Jersey Road · Alderney Avenue · Addison Avenue
Wraparound Extension Drawings for Osterley (TW7) homes: the package and the process
Every wraparound extension drawings we prepare for an Osterley property is drawn to London Borough of Hounslow’s validation standards and tuned to the TW7 constraints above. Here is what the drawing package covers and how the process runs from first survey to approval.
A wraparound extension is what happens when a rear extension and a side return are designed together rather than as two separate projects: the new build wraps around the back corner of the house, turning a galley kitchen and a small rear room into one continuous kitchen, dining and living space running the full width of the plot. It is the most ambitious single-storey option most London terraces and semi-detached houses have, and because it reshapes almost the entire ground floor, it needs careful structural and drainage planning as well as a confident planning application.
DrawingsDirect draws wraparound extensions for full planning and building regulations, with structural calculations for the L-shaped frame and any drainage diversion produced in-house by our MCIAT-chartered team, on a fixed fee. If your project is a single-storey rear addition or a side infill on its own, see our Rear Extension and Side Return Extension pages; if you also want a second storey, see Double Storey Extension Drawings.
What makes a wraparound extension different from a rear or side return alone?
A rear extension adds depth at the back of the house; a side return adds width down the alley; a wraparound does both at once, so the new floor area turns the corner of the original building rather than sitting against just one wall. The result is typically the largest open-plan space a single-storey extension can deliver, but it also means more of the original external wall is removed and more of the roof is new, which raises the structural and drainage stakes compared with either extension on its own. Homeowners who start out planning a rear extension or a side return alone often move to a wraparound once they see how little extra it costs to combine the two, since much of the groundwork, roof structure and glazing is shared between them rather than duplicated.
Do wraparound extensions need full planning permission in London?
Almost always, yes. Permitted development allowances are calculated on combined additions to the original house, and a wraparound's depth plus width together generally exceed the volume and footprint limits that apply to a rear extension or side extension considered separately. A Lawful Development Certificate route is rarely viable for a genuine wraparound.
Conservation area status and Article 4 directions, common across the terraced streets where wraparound extensions are most popular, remove permitted development rights further still, so we design every wraparound on the assumption it will go through full householder planning.
| Route | What it covers | Typical fee |
|---|---|---|
| Full planning permission | Required for almost all wraparound extensions given the combined footprint | Full Planning pack ~£1,600–£2,400 |
| Planning + Building Regulations (structural) | Combined pack including structural calculations for the L-shaped frame and drainage diversion | Planning + Building Regs pack ~£2,200–£3,850 |
| Rear extension alone (comparison) | Smaller single-storey addition, may qualify for permitted development | see Rear Extension Drawings, from £1,100 |
| Side return alone (comparison) | Widens the kitchen only, keeps garden depth unchanged | see Side Return Extension Drawings, from £1,400 |
Wraparound Extension Drawings in Osterley TW7 — FAQs
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