3 Walnut Farm Science Park Lockgate Road Sidlesham West Sussex PO20 7QQ

1. 13 Feb 2026

   Received by South Downs National Park

2. 1 Apr 2026

   Decision issued: PERMIT

3. 27 Jul 2026

   Added to PlanIndex

South Downs National Park granted permission on 1 April 2026, subject to any conditions on the decision notice. Work must normally begin within three years or the permission lapses. More in our guide to what happens after a planning decision.

A lawful development certificate is a legal determination that existing or proposed works do not need planning permission; the merits of the scheme are not considered. More in our guide to planning application types.

• 3 Walnut Farm Science Park Lockgate Road Sidlesham West Sussex PO20 7QQ

  26/00352/PLD Submitted 13 Feb 2026 50 yards away

  Proposed single storey extension to commercial building.

  Granted Lawful development Extension 9 docs
  Small domestic

• Walnut Farm Science Park Lockgate Road Sidlesham West Sussex

  26/01035/FUL Submitted 8 May 2026 50 yards away

  Demolition of existing lean-to building and construction of replacement building within Class E(g) use (office, research, and development and light industry)

  Granted Full applications Demolition 12 docs

• Units 1 And 2 Walnut Farm Science Park Lockgate Road Sidlesham West Sussex PO20 7QQ

  12/00100/COU Submitted 6 Jan 2012 50 yards away

  Storage and preparation of cars.

  Granted Full applications 18 docs

• Units 1 And 2 Walnut Farm Science Park Lockgate Road Sidlesham West Sussex PO20 7QQ

  12/00100/COU Submitted 6 Jan 2012 50 yards away

  Storage and preparation of cars.

  Granted Full applications 18 docs

• Willowdene Nursery Fletchers Lane Sidlesham Chichester West Sussex PO20 7QG

  26/00111/PA3Q Submitted 16 Jan 2026 200 yards away

  Prior Approval of Proposed Change of Use of an existing agricultural building to 1 no' dwellinghouse (Use Class C3), and for associated operational development, under Part 3, Class Q(c) of The Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) which was amended by Statutory Instrument 2024 No. 579 which came into effect on 21st May 2024.

  Awaiting decision Prior approval 12 docs
  Domestic

• Willowdene Nursery Fletchers Lane Sidlesham Chichester West Sussex PO20 7QG

  26/00111/PA3Q Submitted 16 Jan 2026 200 yards away

  Prior Approval of Proposed Change of Use of an existing agricultural building to 1 no' dwellinghouse (Use Class C3), and for associated operational development, under Part 3, Class Q(c) of The Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) which was amended by Statutory Instrument 2024 No. 579 which came into effect on 21st May 2024.

  Awaiting decision Prior approval 12 docs
  Domestic

• SDNP/26/04111/LDP Awaiting decision

  12 The Glade Bucks Horn Oak Farnham Hampshire GU10 4LU

  Certificate of Lawfulness for a Proposed Use - to station a mobile home granny annexe for use incidental to the main dwelling.

  Received 23 Oct, published by the council 2 Nov 2026 Lawful development
• SDNP/26/04049/LDE Awaiting decision

  Coppicefield Cottage, The Annexe Ridge Common Lane Steep Petersfield Hampshire GU32 1AJ

  Use of the building as an independent dwellinghouse

  Received 20 Oct, published by the council 2 Nov 2026 Lawful development
• SDNP/26/03988/LDP Awaiting decision

  53 Hawkenbury Way Lewes East Sussex BN7 1LT

  Removal of the existing uPVC conservatory and erection of a single-storey rear extension; installation of four roof windows to the existing main roof to serve a loft conversion; and a new window at ground-floor level in the side elevation.

  Received 15 Oct, published by the council 26 Oct 2026 Lawful development
• SDNP/26/03957/LDP Awaiting decision

  The Old Barn East Harting Street East Harting West Sussex GU31 5LZ

  Proposed lawful development - window removal and infill. Removal of outer glazed screen to rear entrance portico.

  Received 13 Oct, published by the council 2 Nov 2026 Lawful development
• SDNP/26/03979/LDP Awaiting decision

  Philliswood Cottage Hooksway Lane Hooksway Elsted West Sussex PO18 9JZ

  Single-storey rear conservatory extension.

  Received 13 Oct, published by the council 26 Oct 2026 Lawful development