House extensions in Horsham

Horsham received 236 householder applications in the last 12 months - about 5 a week. Rear extensions and garage works are the most common. Of the 171 decided so far, 160 were approved. If you're planning your own, the applications below show what people nearby applied for and how the council decided.

66 last 90 days
|
25 last 30 days
|
7 last 14 days

Filter applications

Date received Last 90 days

Pick a year, or click two to span the range between them. Records before 2026 come from the archive.

Keywords in the address or description
Match

Literal text matches. For application types (extensions, solar, change of use...) use the categories above - no need to recreate them as keywords.

Showing 50 of 66 applications
DC/26/1038 8 Jul 2026 Registered

Half Hidden London Road Pulborough West Sussex RH20 1AS

Removal of hedgerow and erection of a featherbaord fencing with concrete posts.

Horsham 8 Jul 2026
DC/26/1015 8 Jul 2026 Registered

1 Amberley Road Storrington West Sussex RH20 4JB

Demolition of existing roof structure, conversion of loft into habitable living space with the erection of two infill extensions, infilling two corner...

Horsham 8 Jul 2026
DC/26/1004 7 Jul 2026 Registered

38 Heron Way Horsham West Sussex RH13 6DL

Demolition of existing double garage and erection of a replacement with a two storey side extension. Addition of a pitched roof with glazing to existi...

Horsham 7 Jul 2026
DC/26/1011 2 Jul 2026 Registered

Amberglade Amberley Road Storrington West Sussex RH20 4JQ

Conversion of garage into habitable living space (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham 2 Jul 2026
DC/26/1013 2 Jul 2026 Registered

Tempus Fugit New Hall Lane Small Dole West Sussex BN5 9YH

Demolition of existing conservatory and erection of a single storey rear extension with reduced first floor terrace above, revised fenestration, roof ...

Householder Horsham 2 Jul 2026
DC/26/1053 1 Jul 2026 Registered

41 Cissbury Close Horsham West Sussex RH12 5JT

Prior notification for erection of single storey rear extension, which would project 4m from the rear elevation, comprising a maximum height of 2.8m a...

Gen Permitted Development - Householder Horsham 1 Jul 2026
DC/26/1043 29 Jun 2026 Registered

11 The Birches Mannings Heath West Sussex RH13 6JT

Demolition of conservatory. Erection of a single storey rear extension. Construction of a pitched roof to replace flat roof.

Horsham 29 Jun 2026
DC/26/1027 25 Jun 2026 Registered

8 Kempshott Road Horsham West Sussex RH12 2EY

Erection of a single storey rear extension.

Householder Horsham 25 Jun 2026
DC/26/1023 24 Jun 2026 Registered

51 Brook Road Horsham West Sussex RH12 5FS

Erection of a part single storey, part two storey front extension and installation of a side window.

Householder Horsham 24 Jun 2026
DC/26/1059 23 Jun 2026 Registered

Willow Croft New Road Southwater Horsham West Sussex RH13 9AU

Erection of a side extension to the existing garage with extensions and alterations at roof level to create first-floor ancillary accommodation.

Householder Horsham 23 Jun 2026
DC/26/1005 22 Jun 2026 Registered

Hatches Lynwick Street Rudgwick West Sussex RH12 3DN

Erection of single storey outbuilding (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham 22 Jun 2026
DC/26/1002 22 Jun 2026 Registered

2 Skylark View Horsham West Sussex RH12 5EA

Demolition of existing conservatory and erection of single storey rear extension with removal of rear door to garage.

Householder Horsham 22 Jun 2026
DC/26/0998 19 Jun 2026 Registered

The Oast House Billingshurst Road Ashington West Sussex RH20 3AZ

Reconstruction of collapsed potting shed.

Householder Horsham 19 Jun 2026
DC/26/0995 19 Jun 2026 Registered

17 Cavendish Close Horsham West Sussex RH12 5HX

Demolition of existing garage and erection of new garage (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham 19 Jun 2026
DC/26/0997 19 Jun 2026 Registered

Columbine Bracken Lane Storrington West Sussex RH20 3HS

Replacement of non permeable tarmac driveway with new permeable asphalt surface including new sub base (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham 19 Jun 2026
DC/26/0987 18 Jun 2026 Registered

23 Bedford Road Horsham West Sussex RH13 5BL

Erection of a single storey side extension.

Householder Horsham 18 Jun 2026
DC/26/0983 17 Jun 2026 Registered

Old Pinkhurst Bashurst Hill Itchingfield West Sussex RH13 0NY

Erection of a single storey rear extension, re-roofing of 2no. outbuildings, and relocation of an external boiler. (Listed Building Consent).

Listed Building Consent Horsham 17 Jun 2026
DC/26/0982 17 Jun 2026 Registered

Old Pinkhurst Bashurst Hill Itchingfield West Sussex RH13 0NY

Erection of a single storey rear extension, re-roofing of 2no. outbuildings, and relocation of an external boiler. (Householder Application).

Householder Horsham 17 Jun 2026
DC/26/0981 17 Jun 2026 Registered

59 Billingshurst Road Broadbridge Heath West Sussex RH12 3LJ

Erection of outbuilding in rear garden.

Householder Horsham 17 Jun 2026
DC/26/0977 16 Jun 2026 Registered

4 Widgeon Way Horsham West Sussex RH12 2LX

Erection of two-storey side extension, replacement of front garage door with window and extension of front porch, replacement of rear door with window...

Householder Horsham 16 Jun 2026
NC/26/0018 16 Jun 2026 Decided

Heron Way County Primary School Heron Way Horsham West Sussex RH13 6DJ

Redesign of hard play area, including replacement hardstanding, artificial grass turf and the installation of a gazebo and bike shelter.

Neighbouring Authority Consultation Horsham 16 Jun 2026
DC/26/0939 16 Jun 2026 Registered

Fairlee Bucks Green Rudgwick West Sussex RH12 3JE

Demolition of existing greenhouse and erection of pool house and excavation of swimming pool with associated landscaping works.

Householder Horsham 16 Jun 2026
DC/26/0978 16 Jun 2026 Registered

Beltane Cottage 29 Church Street Steyning West Sussex BN44 3YB

Replacement of 6 steel windows with slim line double glazed Royale Stepped Aluminium Heritage frames (Listed Building Consent).

Listed Building Consent Horsham 16 Jun 2026
DC/26/0962 15 Jun 2026 Registered

16 Ghyll Crescent Horsham West Sussex RH13 6BG

Erection of a first floor side extension over the existing garage, and alterations to fenestration.

Householder Horsham 15 Jun 2026
DC/26/0958 15 Jun 2026 Awaiting decision

21 Timber Mill Southwater West Sussex RH13 9SX

Prior Approval for the erection of a single-storey rear larger home extension, which would project 5.10m from the rear elevation, comprising a maximum...

Gen Permitted Development - Householder Horsham 15 Jun 2026
DC/26/0949 11 Jun 2026 Registered

59 Berrall Way Billingshurst West Sussex RH14 9PQ

Demolition of existing conservatory and erection of a single storey side extension.

Householder Horsham 11 Jun 2026
DC/26/0950 11 Jun 2026 Registered

8 Mallard Close Horsham West Sussex RH12 2NB

Demolition of the existing conservatory and erection of a single storey rear extension, and partial conversion of garage into living accommodation.

Householder Horsham 11 Jun 2026
DC/26/0956 11 Jun 2026 Registered

15 Tern Avenue Horsham West Sussex RH12 5AT

Conversion of garage to habitable space together with the replacement of front garage door with window and installation of window to rear.

Householder Horsham 11 Jun 2026
DC/26/0936 10 Jun 2026 Awaiting decision

September Cottage New Barn Lane West Chiltington West Sussex RH20 2PP

Erection of a single storey detached outbuilding with roof mounted solar panels.

Householder Horsham 10 Jun 2026
DC/26/0935 10 Jun 2026 Registered

54 Primrose Copse Horsham West Sussex RH12 5PZ

Conversion of loft into habitable living space with the installation of a rear dormer and 2no. rooflights to the front elevation. (Lawful Development ...

Certificate Proposed Lawful Use/Dev Horsham 10 Jun 2026
DC/26/0931 9 Jun 2026 Registered

5 Centenary Road Southwater West Sussex RH13 9FR

Erection of a single storey rear extension.

Householder Horsham 9 Jun 2026
DC/26/0918 8 Jun 2026 Registered

Nut Knowle Cottages Brighton Road Woodmancote West Sussex BN5 9SS

Installation of acoustic fencing with pedestrian and access gates to replace the existing picket fence.

Householder Horsham 8 Jun 2026
DC/26/0748 21 May 2026 Registered

25 East Street Horsham West Sussex RH12 1HH

External alterations and repair works to front elevation of building and installation of a cooking extract flue to rear. (Full Application).

Full Application Horsham 21 May 2026
DC/26/0779 20 May 2026 Awaiting decision

67 Church Lane Upper Beeding Steyning West Sussex BN44 3HP

Erection of a single storey rear extension, installation of cladding to the front elevation gable and associated alterations.

Householder Horsham 20 May 2026
DC/26/0721 19 May 2026 Awaiting decision

Hareswith Holt Greenhurst Lane Storrington West Sussex RH20 3EY

Erection of a detached outbuilding comprising ancillary home cinema / games room.

Householder Horsham 19 May 2026
DC/26/0783 19 May 2026 Awaiting decision

40 Corsletts Avenue Broadbridge Heath Horsham West Sussex RH12 3NZ

Erection of a timber framed outbuilding (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham 19 May 2026
DC/26/0707 18 May 2026 Awaiting decision

65 The Spinney Pulborough West Sussex RH20 2AR

Creation of a driveway with steps down to the dwelling and creating a level access platform to the front of the property.

Householder Horsham 18 May 2026
DC/26/0697 18 May 2026 Awaiting decision

Southview Hayes Lane Slinfold West Sussex RH13 0SQ

Conversion of detached garage into habitable living space (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham 18 May 2026
DC/26/0792 15 May 2026 Decided

26 Mill Drive Henfield West Sussex BN5 9RY

Erection of side dormer window and erection of a garden room.

Householder Horsham 15 May 2026
DC/26/0776 14 May 2026 Decided

16 Chanctonbury Ashington West Sussex RH20 3QE

Erection of a single storey side and rear extension.

Householder Horsham 14 May 2026
DC/26/0732 13 May 2026 Registered

Coombewick House Mobile Home London Road Ashington West Sussex RH20 3AU

Temporary siting and residential occupation of mobile home with associated decking and ramped access for a (further) temporary period of three years, ...

Full Application Horsham 13 May 2026
DC/26/0767 12 May 2026 Decided

1 Hydehurst Cottages Dial Post Horsham West Sussex RH13 8NS

Erection of single storey front, side and rear extensions.

Householder Horsham 12 May 2026
DC/26/0828 12 May 2026 Decided

80 Woodlands Way Southwater Horsham West Sussex RH13 9JA

Conversion of garage to additional accommodation with alterations to front, extension to rear and raised roof.

Householder Horsham 12 May 2026
DC/26/0764 11 May 2026 Decided

Chanctonbury Leisure Centre Spierbridge Road Storrington West Sussex RH20 4PG

Erection of a single-storey extension to existing storage area, installation of new first floor windows and internal alterations.

Full Application Horsham 11 May 2026
DC/26/0759 11 May 2026 Awaiting decision

54 Parsonage Road Horsham West Sussex RH12 4AN

Removal or Variation of Condition 4 of previously approved application DC/25/0508 (Erection of a single storey rear extension with roof terrace and re...

Removal of condition Horsham 11 May 2026
DC/26/0753 11 May 2026 Decided

Unit 2 Redkiln Close Horsham West Sussex RH13 5QL

Retention of existing flue

Full Application Horsham 11 May 2026
DC/26/0760 11 May 2026 Decided

18 King Edward Road Christs Hospital West Sussex RH13 0ND

Erection of a single story rear extension.

Householder Horsham 11 May 2026
DC/26/0656 6 May 2026 Decided

53 Bricklayer Lane Faygate West Sussex RH12 0AA

Loft conversion with front dormers and rear rooflights.

Householder Horsham 6 May 2026
DC/26/0692 28 Apr 2026 Decided

Buildings 1 To 4 And 6 And 7 Water Lane Storrington West Sussex RH20 3EA

Proposed extension to form covered entrance to existing external doors.

Full Application Horsham 28 Apr 2026
DC/26/0666 24 Apr 2026 Decided

Cheeleys Burford Road Horsham West Sussex RH13 5SR

Prior Approval for the erection of a single-storey rear larger home extension, which would project 5m from the rear elevation, comprising a maximum he...

Gen Permitted Development - Householder Horsham 24 Apr 2026
Recency
Last 2 weeks
2-4 weeks
1-2 months
Older

Get free email alerts for new extensions applications in Horsham

Set up alerts

Frequently asked questions

When do you need planning permission for a house extension?
Single-storey rear extensions up to 4m (detached) or 3m (semi-detached / terraced) are usually permitted development. Two-storey extensions, anything in a conservation area, or larger projects almost always need a planning application.
What's the difference between planning permission and permitted development?
Permitted development rights let you build certain things without applying for planning permission, subject to specified limits. Anything outside those limits — taller, larger, in a protected area — needs full planning permission.
How long does a householder application take?
The statutory target is 8 weeks from validation. Most simple householder extensions are decided within that window; complex or contested cases (especially with objections) can take longer.
Can I get email alerts for new extensions applications in Horsham?
Yes. Click "Set up alerts" on this page and you'll get a daily or weekly email listing every new extensions application published by Horsham. You can also narrow the alert to a postcode, street, or drawn area.

We check Horsham's planning portal daily. New extensions applications appear here within a day of being published.