346,831 real decisions from 314 UK councils. See what actually gets approved, what gets refused, and why — so you don’t waste thousands on drawings for something your council will reject.
Last updated: June 2026
83.7%
approval rate across 346,831 decisions
That means roughly 1 in 6 rear extension applications are refused — often due to avoidable design issues.
346,831
Decisions
290,433
Approved
56,398
Refused
314
Councils
Rear extensions are the most common home extension in the UK — but not all get approved. Designs that are too deep, too tall, or too close to a neighbour are refused every day.
What these results show
• Most rear extensions are approved — but not all designs succeed.
• Two-storey and deeper extensions (over 4–5m) face significantly more scrutiny.
• Refusals most often cite neighbour impact: loss of light, overlooking, or overbearing scale.
• The same design can be approved in one council and refused in the next — local precedent matters more than national averages.
Real examples showing what works — and what gets refused. Use the filters to compare approved and refused applications.
Seeing similar rear extensions refused? Your property might be in a stricter area — or these patterns might not apply locally. See your local approval pattern →
Prior approval request for the erection of a single storey rear extension with a flat roof that would 1) extend beyond the rear wall of the original house by 5.75m; 2) have a maximum height of 2.80 metres and 3) have eaves that are 2.40 metres high.
Demolition of existing conservatory and single storey kitchen at rear of property. Erection of single storey rear extension to include a flat roof design with feature roof lantern and separate flat roof light. Brickwork to match existing.
Nottingham2 · Wollaton West (May 2019) · Mon 06 Jan 2020
▸ Matching existing materials and design helps approval chances.
REAR EXTENSION TO RETAIL UNIT (CLASS 1A) TO FORM EXTERNAL GARDEN CENTRE SALES AREA (532 SQM) AND STORAGE YARD (216 SQM), ERECTION OF 4.8 METRE HIGH FENCING AND INSTALLATION OF FLOODLIGHTS (6.5M COLUMNS) AND ENLARGEMENT OF EXISTING OPENING IN REAR ELEVATION
Prior notification for the construction of a single storey rear extension to the existing dwelling, measuring 5.5m metres beyond the rear wall; 2.7m in height from ground level; 2.75m metres in height to eaves from ground.
Craven · Skipton West & West Craven · Fri 03 Oct 2025
▸ Single-storey extensions face less scrutiny than two-storey.
Modifications to existing single-storey projection at front of the property along with single-storey pitched roofed side and flat roofed rear extensions
Removal Of Existing Flat Roof To Rear Extension and Installation Of Replacement Pitched Roof And Rooflights, Alterations And Installation Of Stair To Provide Access To First Floor Storage Area
Prior approval submission for a single storey rear extension projecting 3.5 metres from the rear elevation of the original dwellinghouse with a height of 2.9 metres at the eaves and a maximum height of 2.9 metres and having a flat roof with 2no. roof lanterns (Valid from 23.03.2026)
Garage conversion with the replacement of existing garage door to a window. The erection of a single storey rear extension. A loft conversion with rear dormer roof extension.
Notification to determine if Prior Approval is required for a Proposed Larger Home Extension (erection of a single storey rear extension creating a total depth of 5.95m (2.7m existing depth plus a further 3.25m), maximum height 3.95m and eaves height 2.95m)
▸ Excessive depth is a red flag — large extensions face much higher refusal rates.
DC/25/1930/AME
Refused
Non Material Amendment of DC/24/1858/FUL - Front infill extension, garage conversion and rear flat roof extension - Pitched roof to the rear extension.
Expose stone gable and frontage with lime mortar repairs; wet harl outbuildings and extensions; re-roof with slate and stone; internal alterations including new toilets; convert outhouse to kitchen/dining area; add scullery and two storey rear extension; and demolish part of outbuilding to form cour
Application to Determine if Prior Approval is Required for a Proposed Larger Home Extension - single storey rear extension measuring 3m in depth, 2.9m high and 2.4m at the eaves, assessed under the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) Schedule 2
T1 - Yew - Crown lift by 0.5m and crown thin by 20%. T2 - Ash - Reduce branches overhanging road side by 1m. T3 - Beech - Reduce 4 branches overhanging conservatory/rear extension by 1.5 metres.
Replace 2 no front roof windows with Conservation style roof windows, front PVCu door with timber panelled door, exisiting PVCu gutters, downpipes, clips and fittings with cast iron, rear extension concrete tiles with spanish grey slate roof tiles, complete interior rewire, repair internal plasterwo
Erection of a single storey side extension including connection to existing detached garage, part single/part two storey rear extension together with amendments to roof of existing garage
Proposed alterations, rear extension, new dormer windows and pitched roof over existing dormer window to front elevation, infill porch area and lean-to roof in lieu of flat roof to existing side extension
Demolition of rear single storey buildings and erection of single storey side/rear extension, widening of existing front access with provision of new ramp and new glazed doors, creation of new accesses off Cecil Street including works to existing pillars and railings. Installation of polycarbonate p
Retrospective application for a single storey rear extension, installation of 8 roof lights, installation of a set of patio doors and change two windows into patio doors
Deemed consent granted following successful ground (a) appeal against enforcement notice issued under reference ENF/13684/17 (appeal ref: APP/B4215/C/19/3242449) for the the material change of use of first and second floors from self-contained flat (Class C3) to kitchen, storage and ancillary staff
Manchester2 · Didsbury West Ward · Fri 19 Jun 2020
▸ Kitchen/living extensions are the most common approved type.
▸ Modest single-storey extensions within typical depth limits have strong approval rates.
190095/DPP
Approved
Partial change of use from office accommodation (Class 4) to form 13 residential flats on upper floor levels incorporating rooftop extension with terrace; re-cladding of existing rear extension; replacement of doors; refurbishment of an existing windows, formation of new window openings and installa
Request for comments by Bristol City Council on an application that crosses the boundary into an adjoining authority: - Demolition of garage. Erection of two storey rear extension to facilitate subdivision of 1no. dwelling into 3no. dwellings with associated works.
Prior notification of a proposed change of use of ground floor accountants offices (use class A2) to three 1-bed flats (use class C3) including infilling of existing shop front and insertion of windows and entrance doors to the proposed flats plus entrance doors to first floor flats, demolition of s
▸ Single-storey extensions face less scrutiny than two-storey.
11/00917/NMA
Refused
Non-material amendment to planning permission 07/00242/DET (Rear extension, porch extension and erection of conservatory and erection of garage/workshop) - Configuration of main house extension altered and configuration of garage/workshop roof altered.
Proposed single storey rear extension (including part demolition of existing single storey rear extensions) first floor rear extension and Juliet balcony to existing rear elevation.
Erection of single storey rear extension measuring 6 metres in length, with a maximum eaves height of 2.89 metres and maximum overall height of 2.89 metres (Prior Approval)
Proposed demolition of an existing rear store extension and garage. Proposed construction of a wrap around flat roof front, side/rear extension with a canopy extension roof to the rear. Changes to fenestration and addition of a flat roof dormer to create a front entrance extension with full height g
Southribble · Walton-le-Dale East · Fri 06 Mar 2026