Rear extension drawings for Westminster homes, £589
Pimlico’s design guide allows lightwell infill of up to two storeys on unlisted houses if neighbours keep their light, asks for London stock brick, and bars render. We draw to those tests.
- £439 drawings + £150 survey (£589 total)
- Lightwell infill tests
- Article 4 areas checked
What do rear extension drawings cost in Westminster?
We charge £589: £439 for the drawings, forms and submission and £150 for the survey visit, with no VAT to add. Westminster City Council’s application fee is paid to the council.
What the Westminster price covers
- A survey of the back addition, lightwell and garden
- Existing and proposed plans, elevations and sections
- A daylight check against the adjoining properties
- Brick, arch and window details to match the original
- Submission to Westminster and replies to the case officer
| Our drawings and submission paid to us | £439 |
|---|---|
| Measured survey paid to us | £150 |
| Council householder fee paid to the council | £548 |
| Total | £1,137 |
We charge £589 in total. The £548 is paid to the council when the application goes in, and the survey is charged once if you later order building regulations drawings for the same house.
What the Pimlico guide allows at the back
The Pimlico Design Guide notes that most buildings there have rear projections generally less than half the property’s width, from two storeys up to full height. Additional extensions may be acceptable if they do not unacceptably reduce daylight to adjoining properties, and lightwell infill may be acceptable if it causes no loss of amenity and is no more than two storeys on unlisted buildings (Pimlico Design Guide).
On listed buildings the infill should be limited to basement level. Garden space must be left at the rear, and rendering or painting brickwork is not acceptable. For example, a ground-floor infill beside an existing outrigger on a Warwick Way terrace fits the guide, while a full-width extension would not. The guide is a 2004 document written under older policies, so we also read the current City Plan.
Article 4, conservation areas and timing
Westminster has 56 conservation areas, and says some are affected by Article 4 directions, so some alterations that need no permission elsewhere do need it here (Westminster conservation areas). The Queen’s Park Estate direction, from 1981 and revised in 1992 to parts visible from the street, covers alterations visible from the highway (Queen’s Park guide).
Westminster decided 123 of 186 householder applications inside 8 weeks in the year to June 2026, so we draw to the validation points first time.
Westminster rear extensions in numbers
- 2 storeys
- Maximum lightwell infill height on unlisted buildings in the Pimlico Design Guide. Westminster: Pimlico Design Guide (guide to alterations in the Pimlico conservation area)
- Half width
- Rear projections in Pimlico are generally less than half the property’s width. Westminster: Pimlico Design Guide (guide to alterations in the Pimlico conservation area)
- No render
- The Pimlico guide says rendering or painting brickwork is not acceptable. Westminster: Pimlico Design Guide (guide to alterations in the Pimlico conservation area)
- 56
- Conservation areas in Westminster. Westminster: conservation areas
- 1981
- Year Westminster introduced the Queen’s Park Estate Article 4 direction, revised in 1992. Westminster: Queen’s Park Estate design guide
- 123 of 186
- Westminster City Council householder applications decided within 8 weeks in the year to June 2026, out of all it decided (prior approvals not counted). MHCLG live table PS2, planning application statistics by district, July 2025 to June 2026 (GOV.UK)
- £96.97 per m²
- The Mayor of London’s CIL in Westminster (band 1) for permissions granted in 2026, owed only when a scheme is liable for CIL in the first place. Mayoral CIL: annual rate summary for 2026, Table 1 (Greater London Authority)
Westminster rear extension questions
Can I infill my Pimlico lightwell?
Possibly, up to two storeys on an unlisted building, if neighbours lose no amenity. On a listed building only at basement level.
Can I render the new brickwork?
No. The guide says rendering or painting is not acceptable.
Does Queen’s Park have an Article 4 direction?
Yes, for parts of properties visible from the street.
How fast does Westminster decide?
It decided 123 of 186 householder cases within 8 weeks last year. We cannot promise a date.
Other services people book with this one
- Prior approval for a larger home extension£349 drawings + £150 survey (£499 total)
- Lawful Development Certificate drawings£389 drawings + £150 survey (£539 total)
- Building regulations drawings£479 drawings + £150 survey (£629 total)
- Side return extension drawings£479 drawings + £150 survey (£629 total)
- Party wall notice£39
Price your Westminster extension
Send the address and a sketch. We check the area guide and reply with a fixed price.