Double Storey Extension Drawings in Clerkenwell EC1R
Fixed-fee, MCIAT-chartered double storey extension drawings for Clerkenwell (EC1R) homeowners — London Borough of Islington validation and local constraints handled from the start.
Clerkenwell (EC1R) sits at the southern edge of Islington, where the housing is dominated by former Georgian and Victorian workshops, warehouses and print-trade buildings now converted to flats and live/work lofts. Reconfiguration, loft and mansard additions and change-of-use applications are far more common here than the rear extensions typical of Islington's residential streets, and Islington's design expectations for this historic fabric are demanding.
Much of the neighbourhood falls within or beside conservation areas such as Charterhouse Square, Hatton Garden and Smithfield, so alterations to facades, windows and rooflines face tight control. We establish exactly where a Clerkenwell property sits against those boundaries before drawing, and prepare the application to Islington's validation and design standards so it is assessed without a query.
Planning in Clerkenwell (EC1R): what to know before you apply
EC1R has no published householder Article 4 direction affecting typical residential work, but Clerkenwell's dense conservation coverage and its high proportion of converted warehouse and workshop buildings mean permitted development cannot be assumed — mansard, roof-terrace and change-of-use proposals are the ones most closely scrutinised.
Typical Clerkenwell housing stock
Converted Georgian and Victorian workshops, warehouses and print-trade buildings turned into flats and live/work lofts, interspersed with surviving terraces and a handful of newer infill blocks between Farringdon and the City Road end.
Streets we regularly draw for in Clerkenwell
Duncan Terrace · Laystall Street · Graham Street · Doughty Street
What the wider borough is built of
EC1R has too few classified residential buildings to publish a district figure of its own, so we do not estimate one. The measured figures below are borough-wide and EC1R is not among the districts they cover.
Borough-wide building mix
Residential building form across 3 of the borough's 4 postcode districts, from 1,096 classified buildings. EC1R is below the publication floor and is excluded from these totals, so they describe the borough around it rather than the district itself.
| Attached on more than one side | 74% |
|---|---|
| Attached on one side | 21% |
| Detached | 5% |
| Buildings attached on more than one side | 809 |
| Detached buildings | 52 |
| Buildings classified | 1,096 |
| Postcode districts measured | 3 |
Source: Ordnance Survey National Geographic Database (derived statistics). Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Extracted 2026-08-17.
Double Storey Extension Drawings for Clerkenwell (EC1R) homes: the package and the process
At first-floor level the drawings have to answer for daylight, privacy and massing. That means proposed elevations showing every new window with its position relative to the boundary, a section taken through the extension and the neighbouring building, and a roof form drawn to sit below the existing ridge rather than compete with it.
We draw the neighbouring property alongside your own, because the officer's assessment is comparative — the effect on their windows and outlook is the test. Setting the first floor in from the boundary, and showing that set-back as a dimension, resolves most objections before consultation begins.
At first floor the boundary relationship decides everything. A detached house has room to set the addition in on both sides; a semi has one shared wall and one clear flank; a mid-terrace can usually only go to the rear, where the effect on both neighbours has to be drawn.
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
Matching the roofline and materials
Planning officers assess a double storey extension heavily on how convincingly it reads as part of the original house rather than an addition bolted onto the side. Our drawings match ridge height, roof pitch, eaves detail and brick or render finish to the existing building wherever the design brief allows, which is consistently one of the strongest factors in securing approval without delay or redesign. Where a subtly contrasting material is proposed instead — a different brick tone, or a zinc or slate roof against a tiled original — we set it out clearly on the elevations so the design intent reads as deliberate rather than a mismatch, which is how most London boroughs prefer a genuine design statement to be presented.
| 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 Clerkenwell EC1R — 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 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?+
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