12 St Leonards Avenue, Harrow, HA3 8EL

1. 12 Oct 2006

   Received by Harrow

2. 16 Jan 2007

   Validated

   Checked as complete and ready for consideration.

3. 5 Mar 2007

   Decision issued: Grant

4. 6 Sep 2026

   Added to PlanIndex

Permission has been granted, usually subject to conditions listed on the decision notice, some of which must be discharged before work starts. The decision notice on the council portal sets out exactly what was approved.

Work must normally begin within three years of the decision or the permission lapses. Neighbours cannot appeal a grant; challenging one means judicial review of how the decision was made, within tight time limits.

A lawful development certificate is a legal determination, not a planning judgement. It asks the council to confirm either that existing use or works are lawful, often through the passage of time, or that a proposal would not need planning permission at all. The applicant must prove the facts; the merits of the scheme are not considered.

More on lawful development applications in our guide

• 10 St Leonards Avenue, Kenton, Harrow, HA3 8EL

  P/0800/18 Submitted 27 Feb 2018 0m away

  Single storey front and two storey side to rear extension incorporating front porch; single storey rear extension; rear dormer; rooflight in front roofslope to create habitable roofspace (demolition of conservatory)

  Refused Householder Extension Loft or dormer +1 10 docs
  Small domestic

• 8 St Leonards Avenue, Harrow, HA3 8EL

  EAST/899/02/FUL Submitted 12 Jul 2002 0m away

  Single storey rear extension

  Granted Full applications Extension
  Small domestic

• 12 St Leonards Avenue, Harrow, HA3 8EL

  P/2334/07 Submitted 19 Jul 2007 0m away

  Two storey side to rear extension rear dormer single storey front side and rear extension

  Granted Full applications Extension Loft or dormer 26 docs
  Small domestic

• 12 St Leonards Avenue, Harrow, HA3 8EL

  P/0990/07 Submitted 2 Apr 2007 0m away

  Two storey side to rear extension; rear dormer; single storey front side and rear extensions

  Decided Full applications Extension Loft or dormer 22 docs
  Small domestic

• 20 Kingshill Avenue, Kenton, Harrow, HA3 8JP

  PL/0886/24 Submitted 27 Mar 2024 96m away

  Single storey rear extension; first floor rear extension; rear dormer; rooflights in front, side, and rear roof slopes; external alterations

  Granted Householder Extension Loft or dormer
  Small domestic

• 16 Kingshill Avenue, Kenton, Harrow, HA3 8JP

  P/0131/18 Submitted 11 Jan 2018 96m away

  Rear dormer to create habitable roofspace; three rooflights in front roofslope

  Refused Householder Loft or dormer 11 docs
  Domestic

• PL/1761/26 Status unknown

  1 Middle Road, Harrow On The Hill, Harrow, HA2 0HW

  Certificate of lawful development (proposed): Replacement of ground floor front bay window

  29 Jun 2026 Lawful development
• PL/1772/26 Status unknown

  114 Somervell Road, South Harrow, Harrow, HA2 8TT

  Certificate of Lawful Proposed Development: Demolition and replacement of first floor level and roof

  29 Jun 2026 Lawful development
• PL/1735/26 Status unknown

  222 Malvern Avenue, South Harrow, Harrow, HA2 9HE

  Certificate of lawful development (proposed): Rear dormer; installation of rooflight in front roofslope

  24 Jun 2026 Lawful development
• PL/1716/26 Status unknown

  59 Leamington Crescent, South Harrow, Harrow, HA2 9HH

  Certificate of Lawful Development (Proposed): Garden room with garden tools storage at rear (demolition of detached garage)

  22 Jun 2026 Lawful development
• PL/1696/26 Status unknown

  31 Chandos Road, Harrow, HA1 4QX

  Certificate of Lawful Development (Proposed): Alterations and extension to roof to form end gable; rear dormer; two rooflights in front roof slope; window in end gable

  22 Jun 2026 Lawful development