House extensions in Horsham

Horsham received 701 householder applications in the last 12 months - about 13 a week. Rear extensions and garage works are the most common. Of the 537 decided so far, 515 were approved. If you're planning your own, the applications below show what people nearby applied for and how the council decided.

Date received
Get alerts for Horsham

Filter applications

Date receivedLast 90 days
Date receivedLast 90 days
Select one year, or two for a range.
Number of homesAny
StatusAny
Application routeAny
Application type1 selected
KeywordsNone
Match

Matches words or phrases in the application address and description.

Showing 50 of 182 applications
22 Oct 2026 Registered DC/26/1510

Mill Cottage Brooks Green Road Coolham West Sussex RH13 8GR

Erection of single storey rear extension

Householder Horsham
21 Oct 2026 Registered DC/26/1572

Farren Court The Street Cowfold West Sussex RH13 8BP

Erection of single storey side extension and alterations to existing office building.

Full Application Horsham
20 Oct 2026 Registered DC/26/1584

41 Furners Mead Henfield West Sussex BN5 9JA

Replacement of existing original hanging tiles with external wall insulation and silicone render.

Householder Horsham
19 Oct 2026 Awaiting decision DC/26/1412

Windmill Cottage Old Mill Place Pulborough West Sussex RH20 2DR

Erection of a detached two storey three bedroom dwelling with garage and outdoor swimming pool. Erection of a garage for the host dwelling.

Full Application Horsham
19 Oct 2026 Registered DC/26/1014

The Henfield Club Cagefoot Lane Henfield West Sussex BN5 9HD

Replacement of 4no. existing metal/crittal windows in the western elevation with uPVC windows (Listed Building Consent).

Listed Building Consent Horsham
19 Oct 2026 Registered DC/26/1520

33 Shottermill Horsham West Sussex RH12 5HG

Demolition of existing conservatory and erection of single storey rear extension (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham
19 Oct 2026 Registered DC/26/1193

8 Millais Horsham West Sussex RH13 6BS

Erection of a single storey rear and side extension and alteration to the fascia over the front elevation.

Householder Horsham
16 Oct 2026 Registered DC/26/1573

7 Cleve Way Billingshurst West Sussex RH14 9RW

Erection of a two storey side extension, side dormer and associated alterations.

Householder Horsham
15 Oct 2026 Registered DC/26/1338

Stane Street Hollow Stane Street Codmore Hill Pulborough West Sussex RH20 1BG

Replacement of first floor front windows, front door and first floor side window (Listed Building Consent).

Listed Building Consent Horsham
14 Oct 2026 Registered DC/26/1628

4 Lanark Close Horsham West Sussex RH13 5RY

Conversion of garage including construction of bay window to front elevation. Replacement of existing flat roof with shallow mono-pitch roof.

Householder Horsham
14 Oct 2026 Awaiting decision DC/26/1175

Thatches Forest Road Horsham West Sussex RH12 4HL

Replacement of existing thatched roof covering with slate tiles.

Householder Horsham
13 Oct 2026 Registered DC/26/1709

Jersey Cottage Horsham Road Cowfold Horsham West Sussex RH13 8BU

Replacement windows and door

Householder Horsham
13 Oct 2026 Registered DC/26/1627

19 Bentley Gardens Broadbridge Heath West Sussex RH12 3XG

Erection of single storey rear infill extension (Lawful Development Certificate - Proposed)

Certificate Proposed Lawful Use/Dev Horsham
13 Oct 2026 Registered DC/26/1622

Morgans Green, Downies Cottage The Haven Billingshurst West Sussex RH14 9BJ

Demolition of rear conservatory and single storey rear and side extensions. Erection of single storey rear extension and two storey side extension and...

Householder Horsham
13 Oct 2026 Registered DC/26/1623

Bulls Farm To The South of Top Paddock Campsite Kerves Lane Horsham West Sussex RH13 6RJ

Prior notification for erection of an open fronted storage shelter.

Agricultural Prior Notification Horsham
12 Oct 2026 Registered DC/26/1616

Woodlands Hayes Lane Slinfold West Sussex RH13 0SA

Erection of pitched roof detached garage, replacement of front boundary hedging with new fencing, gates, planting and granite setts.

Householder Horsham
12 Oct 2026 Registered DC/26/1612

45 Shepherds Way Horsham West Sussex RH12 4LZ

Demolition of the existing rear conservatory, construction of a two-storey rear extension, mono-pitched roof over the front study and porch in place o...

Householder Horsham
12 Oct 2026 Registered DC/26/0702

The Steyning Centre Fletchers Croft Church Street Steyning West Sussex BN44 3XZ

Replacement of existing entrance automatic swing doors and addition of external automatic sliding doors.

Full Application Horsham
12 Oct 2026 Registered DC/26/1459

Oaklands Paddock Pulborough Road Cootham West Sussex RH20 4JN

Erection of a carport.

Householder Horsham
9 Oct 2026 Registered DC/26/1609

Copper Beeches The Street Thakeham West Sussex RH20 3EP

Erection of single storey rear and side extension.

Householder Horsham
9 Oct 2026 Registered DC/26/1608

4 The Green Old Guildford Road Broadbridge Heath West Sussex RH12 3JY

Erection of 2no rear dormers.

Householder Horsham
8 Oct 2026 Registered DC/26/1673

Oak Tree Cottage Golding Lane Mannings Heath Horsham West Sussex RH13 6JX

Erection of a front porch and pitched roof.

Householder Horsham
8 Oct 2026 Registered DC/26/1604

Glebe Barn Old Rectory Lane Pulborough West Sussex RH20 2AF

Erection of single storey front extension and rear roof extension.

Householder Horsham
8 Oct 2026 Registered DC/26/1603

Land South of Stoneleigh Tower Hill Horsham West Sussex

Erection of detached garage with associated driveway.

Full Application Horsham
8 Oct 2026 Registered DC/26/1477

Hills Farm The Village Ashurst West Sussex BN44 3AS

Conversion of outbuildings, with extensions and alterations, to enlarge existing annexe (Listed Building Consent) (Retrospective).

Listed Building Consent Horsham
8 Oct 2026 Registered DC/26/1476

Hills Farm The Village Ashurst West Sussex BN44 3AS

Conversion of outbuildings, with related extensions and alterations, to enlarge annexe (Householder)(Retrospective).

Householder Horsham
7 Oct 2026 Registered DC/26/1667

25 Greenfields Way Horsham West Sussex RH12 4LF

Demolition of garage and erection of side and rear extensions, with alterations to driveway and landscaping works.

Householder Horsham
7 Oct 2026 Registered DC/26/1666

11 Merryfield Drive Horsham West Sussex RH12 2AA

Demolition of garage and erection of single storey side and rear extension.

Householder Horsham
7 Oct 2026 Registered DC/26/1482

Palmers Barn, The Boathouse West Chiltington Lane Coneyhurst West Sussex RH14 9DN

Erection of a side extension and front porch extension.

Householder Horsham
6 Oct 2026 Registered DC/26/1591

51 Pulborough Road Storrington West Sussex RH20 4HJ

Erection of a single storey rear extension and associated alterations.

Householder Horsham
5 Oct 2026 Registered DC/26/1661

26 Hill Mead Horsham West Sussex RH12 2PU

Demolition of existing garage and erection of a single storey side and rear extensions.

Householder Horsham
5 Oct 2026 Registered DC/26/1589

Well Cottage Emms Lane Brooks Green West Sussex RH13 0TR

Erection of single storey rear extension.

Householder Horsham
5 Oct 2026 Registered DC/26/1450

7 Borough Gate High Street Steyning West Sussex BN44 3SB

Replacement of windows, doors and conservatory.

Householder Horsham
2 Oct 2026 Registered DC/26/1577

Marden Littleworth Lane Partridge Green West Sussex RH13 8JF

Conversion of existing detached outbuilding into annexe.

Householder Horsham
1 Oct 2026 Registered DC/26/1202

Gorselands Common Hill West Chiltington Pulborough West Sussex RH20 2NL

Erection of two-storey rear extension.

Householder Horsham
30 Sept 2026 Registered DC/26/1566

18 Guildford Road Horsham West Sussex RH12 1LS

Demolition of existing conservatory and roof and erection of single storey rear extension with associated alterations.

Householder Horsham
29 Sept 2026 Registered DC/26/1466

Pavilion Blackstone Lane Blackstone West Sussex BN5 9TA

Erection of a single storey side extension to create Parish Council meeting room and offices.

Full Application Horsham
29 Sept 2026 Registered DC/26/1473

Willows 25 Rookwood Park Horsham West Sussex RH12 1UB

Erection of a detached double garage.

Householder Horsham
29 Sept 2026 Registered DC/26/1460

Beulah Villa 25 Hayes Lane Slinfold West Sussex RH13 0SQ

Demolition of existing side extension, and erection of single-storey side / rear extensions with associated alterations.

Householder Horsham
29 Sept 2026 Registered DC/26/1442

51 Olive Close Horsham West Sussex RH12 4TH

Erection of first floor side extension and alterations to side and rear elevation fenestrations.

Householder Horsham
28 Sept 2026 Registered DC/26/1552

46 Queensway Horsham West Sussex RH13 5AY

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

Householder Horsham
28 Sept 2026 Registered DC/26/1544

17 Thornden Cowfold West Sussex RH13 8AG

Siting of single storey mobile home for ancillary use to the main dwelling (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham
28 Sept 2026 Registered DC/26/1194

31 Friday Street Warnham West Sussex RH12 3QY

Extension of existing garden office and replacement of gazebo.

Householder Horsham
28 Sept 2026 Registered DC/26/1100

Rusper County Primary School Horsham Road Rusper Horsham West Sussex RH12 4PR

Erection of a single storey portable building.

Full Application Horsham
25 Sept 2026 Registered DC/26/1542

Greenfield Farm Valewood Lane Barns Green West Sussex RH13 0QJ

Erection of 2no. single storey day room / utility buildings associated with approved residential caravan pitches.

Full Application Horsham
25 Sept 2026 Registered DC/26/1539

Barns Green Village Hall Muntham Drive Barns Green West Sussex RH13 0PT

Replacement of two awnings with a fixed canopy with glazed roof.

Full Application Horsham
25 Sept 2026 Registered DC/26/1533

Hinkhurst Emms Lane Brooks Green West Sussex RH13 0TR

Conversion of existing garage with the installation of windows and doors to create additional ancillary annexe accommodation.

Householder Horsham
25 Sept 2026 Registered DC/26/1425

Springwells House 9 High Street Steyning West Sussex BN44 3GG

Installation of an internal staircase and lift serving the ground and first floors. (Listed Building Consent).

Listed Building Consent Horsham
25 Sept 2026 Registered DC/26/1405

58 Thelton Avenue Broadbridge Heath West Sussex RH12 3LT

Demolition of an existing conservatory and erection of a single story rear extension (Lawful Development Certificate - Proposed).

Certificate Proposed Lawful Use/Dev Horsham
24 Sept 2026 Registered DC/26/1536

9 Easton Crescent Billingshurst West Sussex RH14 9TU

Erection of a part single-storey / part two-storey rear extension. first floor front extension and alterations to fenestration.

Householder Horsham
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, whether taller, larger or 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 those drawing a lot of comments, 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.