
Double Storey Extension Drawings in Belsize Park NW3
Fixed-fee, MCIAT-chartered double storey extension drawings for Belsize Park (NW3) homeowners — London Borough of Camden validation and local constraints handled from the start.
Belsize Park in NW3 is a conservation-controlled quarter of substantial Victorian villas and Edwardian mansion flats climbing toward Hampstead Heath. Most instructions here are rear and side-return extensions, full loft conversions and the reconfiguration of large houses already split into flats, all needing carefully evidenced householder or full planning applications.
Because the Belsize and Parkhill conservation areas govern almost every elevation, we draw schemes that keep original roof lines, window rhythm and stucco or brick detailing intact, and prepare the design-and-access justification Camden Council expects for heritage-sensitive alterations before anything is submitted.


Planning in Belsize Park (NW3): what to know before you apply
There is no published householder Article 4 direction here, but conservation-area designation removes much permitted development and makes materials, rooflines and rear-extension depth the decisive issues; near-Heath tree protection is common.
Typical Belsize Park housing stock
Large stucco-fronted and red-brick Victorian villas, many long since subdivided into flats, sit alongside purpose-built Edwardian mansion blocks. Generous rear gardens back onto the streets running up towards Parliament Hill and Hampstead Heath.
Streets we regularly draw for in Belsize Park
South Hill Park · Constantine Road · Roderick Road · Courthope Road
Double Storey Extension Drawings for Belsize Park (NW3) homes: the package and the process
Every double storey extension drawings we prepare for an Belsize Park property is drawn to London Borough of Camden’s validation standards and tuned to the NW3 constraints above. Here is what the drawing package covers and how the process runs from first survey to approval.
A double storey extension builds a second floor above a single-storey side or rear addition, typically adding a bedroom and bathroom upstairs over a widened kitchen or reception room below. Because the foundations and roof of a single-storey extension already carry most of the fixed cost of building, adding a floor on top is often the most cost-effective way to gain two rooms rather than two separate projects. The trade-off is scrutiny: a two-storey addition sits closer to eye level with neighbouring windows and gardens, so councils examine massing, roofline and boundary distance more closely than they would a single-storey extension.
DrawingsDirect draws double storey side and rear extensions for full planning and building regulations, with structural calculations for the additional floor load and foundations produced in-house by our MCIAT-chartered team, on a fixed fee. If a single storey is enough, see our Rear Extension and Side Return Extension pages, or combine both with a Wraparound if you are extending sideways as well as up.
Do I need planning permission for a double storey extension in London?
Almost always. Permitted development rights for two-storey extensions are far more restrictive than for single-storey work, particularly on how close the new structure can come to a boundary and how closely its roof pitch and eaves height must match the existing house, so most double storey projects are drawn and submitted as full householder planning applications rather than relying on permitted development.
Where the property sits in a conservation area or is subject to an Article 4 direction, any remaining permitted development allowance for a second storey is typically removed entirely, reinforcing the need for a full application. We check your property's status and your borough's design guidance before drawing.
How do councils control the impact of a double storey extension on neighbours?
Because a second storey introduces new windows and massing at first-floor level, London boroughs apply design guidance aimed specifically at protecting neighbouring light, privacy and outlook.
- The 45-degree rule, tested at neighbouring windows, to check the extension does not block an unreasonable amount of daylight
- A common design expectation that a two-storey side extension is set in roughly 1 metre from the shared boundary, rather than built hard against it
- A first floor commonly set back from the ground floor front elevation, so the upper storey reads as subordinate to the main house from the street
- Obscure or high-level glazing on flank walls facing directly into a neighbour's garden or windows, to limit overlooking
| Option | What it adds | Typical fee |
|---|---|---|
| Single-storey rear extension | A ground-floor kitchen-diner only, may qualify for permitted development | see Rear Extension Drawings, from £1,100 |
| Double storey side or rear extension | Two rooms across two floors, usually needs full planning | Full Planning pack ~£1,600–£2,400 |
| Double storey + Building Regulations (structural) | Combined pack including structural calculations for two-floor loads and foundations | Planning + Building Regs pack ~£2,200–£3,850 |
| Wraparound (rear + side return) | Combines two single-storey extensions into one L-shaped ground floor | see Wraparound Extension Drawings, from £2,200 |
Double Storey Extension Drawings in Belsize Park NW3 — FAQs
How much does a double storey extension cost to design in London?+
Do I need planning permission to add a second storey?+
Will a double storey extension overlook my neighbour's garden?+
Do I need an architect for a double storey extension?+
How long does it take to get double storey extension drawings?+
Do I need planning permission for a rear extension in Camden?+
What is a Basement Impact Assessment and will I need one in Camden?+
Can I make changes to a listed building in Camden?+
How long does Camden take to decide an application?+
How much do planning drawings cost in Camden?+
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