Annexe planning permission examples — what gets approved & refused
21,635 real decisions from 308 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
82.5%
approval rate across 21,635 decisions
That means roughly 1 in 6 annexe applications are refused — often due to avoidable design issues.
21,635
Decisions
17,856
Approved
3,779
Refused
308
Councils
Annexe applications cover self-contained living spaces within a property — from garage conversions to purpose-built garden annexes for elderly relatives. Councils often condition that the annexe remains ancillary to the main dwelling.
What these results show
• Annexes for elderly or disabled relatives are viewed more favourably than general-purpose annexes.
• Councils almost always condition that the annexe remains ancillary — it cannot be sold or let separately.
• Garden annexes with separate entrances and kitchens face more scrutiny as they can appear to be separate dwellings.
• Garage-to-annexe conversions generally have higher approval rates than new-build garden annexes.
⚠️ These are national examples. Your council could be stricter — or more lenient. See what actually gets approved on your street →
Real annexe decisions
Real examples showing what works — and what gets refused. Use the filters to compare approved and refused applications.
Refused
NON MATERIAL AMENDMENT TO APPLICATION 2022/0556/HHA (DOUBLE GARAGE EXTENSION WITH HOME OFFICE ANNEXE ABOVE AND SEPARATE OAK FRAMED CAR PORT - RESUBMISSION OF PLANNING APPLICATION 2021/0809/HHA) - TO REDUCE EXTENSION FOOTPRINT, REPLACEMENT OF LEAN TO STRUCTURE WITH OPEN STORAGE AREA WITH FLAT ROOF, R
Approved
To renew existing roof covering; replace degraded flat roof material on the annex. Remove existing felt cover and replace with like for like glass reinforced plastic (grp) laminate roofing at Holloway Lodge, B79 7NA
Refused
Retrospective application for the construction of detached single storey residential annexe at rear of house; installation of 1.8m fence; alterations (Class C3)
Approved
Consultation from Waverley Borough Council for the erection of extensions and alterations including creation of a basement level and raising of roof ridge height to provide habitable accommodation in roof space with associated landscaping following demolition of existing single storey extension and
▸ Single-storey extensions face less scrutiny than two-storey.
Approved
Annexe extension to side of dwelling with attic room, kitchen extension at rear, dormer to main roof at front and removal of existing garage and canopy
▸ Rear dormers are far more likely to be approved than front-facing ones.
Approved
Conversion of existing garage into a 2 bed annexe. Erection a single storey rear extension and rear dormer roof extension
▸ Single-storey extensions face less scrutiny than two-storey.
Approved
Western Red Cedar (T1) Crown lift all round to approx 5m (property gutter level) Prune back the crown on the N/W side by up to 2m to clear the corner of the property. Remove 2 large stems on the east side of the tree to significantly reduce the overhang of the adjacent property.Plum, Lawson Cypress,
Refused
Non material amendment to planning permission 13/00742/FUL to include alterations to doors and windows, reorientation of roof to single storey annex to the side and use of natural stone to front and side annex elevations
052975
Approved
Change of use to the existing building from sui generis to a warehouse (Use Class B8) and erection of a 3-storey extension to the front to provide ancillary display showroom at ground floor with ancillary accommodation above, refurbishment of the warehouse, including recladding, installation of 2 ro
Approved
Application for Listed Building Consent - Repairs and alterations to existing mill to facilitate conversion to residential annexe (revised proposals to commenced approval 18/00096/FUL).
▸ Listed building applications succeed when design is sensitive to the original character.
240977/DPP
Approved
Conversion of existing garage outbuilding to form self-contained ancillary annex accommodation, including installation of new windows, rooflights and cladding
Approved
Non-material amendment for CH/16/321 to reposition proposed annexe 2m from bound
Approved
Listed Building Consent for internal alterations and canopy extension to existing domestic outbuilding to create ancillary family accommodation / annexe (former stables)
▸ Listed building applications succeed when design is sensitive to the original character.
Approved
EXTENSION TO THE WEST OF THE SCHOOL BUILDING TO PROVIDE SCHOOL HALL, CLASSROOM, OFFICES, STAFF ROOM, TOILETS AND OTHER ANCILLARY ACCOMMODATION. PARTIAL REMOVAL OF EXISTING BOUNDARY WALL, PARTIAL RE-ROOFING OF EXISTING BUILDING, INTERNAL REMODELLING OF EXISTING BUILDING, CONSTRUCTION OF NEW STONE BOU
Refused
Certificate of Lawfulness for proposed development - removal of existing garage and erection of a single storey side extension for use an annexe to main dwelling
Refused
Self-build construction of a three storey, 4-bedroom multigenerational family home, with associated landscape, private and communal amenity space, car parking, cycle parking and ancillary accommodation, plus associated highway and landscape works (revised location plan and proposed hard landscaping
▸ Loss of garden or amenity space can trigger refusal, especially in dense areas.
23/01789/LDP
Approved
Certificate to confirm that the details submitted do not require planning permission. (alterations to the existing domestic annexe)
Approved
Installation of solar panels on roof of main building and annex building
Approved
1. Scots Pine (T16 on tree survey map) - a branch overhanging a neighbouring property which is growing into their garage/annexe roof and has caused leaking damage. Tree surgeon recommended cutting branch back to existing growth point which will allow healthy growth and reduce future risk of damaging
Approved
Construction of a 5 storey block comprising of four 1-bedroom flats and ten 2-bedroom flats including part semi basement level comprising ancillary accommodation, external landscaping and cycle/refuse storage
Still scrolling?
You’re looking at national data. 18% of annexe applications get refused — but that number could be higher or lower in your area.
See what gets approved near your home →
Approved
Converting existing garage to granny annexe with front dormer
▸ Rear dormers are far more likely to be approved than front-facing ones.
Approved
Change of use of first floor including annex from offices to 1 No. two bedroom apartment retaining the ground floor in commercial use
Approved
Erection of a detached annex in the rear garden to form additional living accommodation
Approved
Demolition of existing entrance porch; erection of new garage and vestibule; erection of new external balcony from dining room; conversion of former ground floor garage and store to granny flat.
Approved
Conversion and extension to existing garage to create an annexe.
Approved
Replacement of annex building concrete tiled roof with a standing seam roof system
▸ Replacing an existing structure is generally viewed more favourably than building new.
Approved
The erection of a detached residential annex with associated works within the curtilage of Old Manor House (amended).
Approved
Trim height and spread of 1no. Portuguese Laurel to clear annex and allow access for works at St Paul's Nursery - tree in a conservation area
▸ Sympathetic design in conservation areas can still get approved.
2012/1256
Approved
Conversion of former retail unit (no.1A) into living annexe in association with adjoining house (no. 1) and alterations to frontage of no. 5A
Approved
Article 18 consultation from Salford Council (ref. 22/80765/HH) for existing pool house to be converted to granny annex
Approved
Alterations, conversion of existing garage/shed to an ancillary granny annexe and provision of replacement windows/doors
▸ Replacing an existing structure is generally viewed more favourably than building new.
Approved
Certificate of Lawfulness - Proposed for conversion of existing garage to habitable ancillary accommodation
Approved
Certificate of Lawfulness (Existing): Confirmation that annexe is associated with Thorpe Grange
22/00696/FUL
Approved
Outbuilding within domestic curtilage to form detached annex residential accommodation
Approved
Trees in Conservation Area Notification - Group of Plum trees (G1 on plan) reduce height by up to 2. 5 metres, proportionately reduce length of branches that overhang the driveway of The Vicarage, crown lift over the driveway to 2.5 metres above ground level and prune to clear annexe by up to 0.5 me
▸ Sympathetic design in conservation areas can still get approved.
Approved
One-and-a-half story extension to existing house with annexe, associated car parking and terraces
Approved
Use of premises as a single private dwelling house and installation of garage door and velux windows on rear building and use as altered as an annex.
Approved
Certificate of Lawful Use (Proposed): the siting of a mobile home for use as an annexe ancillary to existing dwelling
Refused
The proposed conversion an existing garage into an annex with associated works
Refused
Conversion of Detached Garage to form Ancillary Accommodation
Refused
CERTIFICATE OF LAWFULNESS (PROPOSED) FOR ALTERATIONS TO DETACHED DOMESTIC GARAGE TO FORM DETACHED DOMESTIC ANNEXE
62/62/25/001
Refused
Lawful development certificate for the existing use of ancillary accommodation a
25/01998/FULL
Refused
Two storey extension to side of dwellinghouse for self-contained ancillary accommodation
▸ Two-storey extensions face higher scrutiny due to greater neighbour impact.
Refused
Change of use of the existing rear outbuilding to a residential annexe (Retrospective)
Refused
CHANGE OF USE OF RESIDENTIAL ANCILLARY ANNEX (C3) TO A SELF CONTAINED 1 BEDROOM APARTMENT WITH ALTERATIONS TO ELEVATIONS.
Refused
Removal of single storey annexe at rear of dwellinghouse and erection of single storey rear extension with associated internal alterations
Refused
Partial demolition and rebuilding of existing swimming pool building to form garage and ancillary residential annex
Refused
Non Material Amendment to planning permission 11/0567/RSP: Replacement of existing front window with a door (to provide front access from granny annex which has existed since mid 1960's and always had its own separate entrance)
Refused
Erection of a single-storey garden annexe to provide ancillary accommodation associated with the existing dwelling, following demolition of the existing garage
Approved
Demolition of car sales office, ancillary accommodation & storage buildings (Prior Notification)
Approved
Erection of single storey rear extension for dependent relative accommodation
▸ Single-storey extensions face less scrutiny than two-storey.
Approved
Installation of a mobile home (to provide annexe accommodation)
Approved
Demolition of car sales office, ancillary accommodation & storage buildings (Prior Notification)
Approved
Part Retrospective: Restoration of pumphouse including extension to form a dwelling and part use as a visitor centre. Restoration of mill for use as annex including re-instatement of scoopwheel and sails.
24/00492/LAW
Approved
Siting of a caravan for ancillary accommodation use (proposed)
Refused
Erection of first floor extension to existing garage and conversion of garage to granny flat,
Refused
SECTION 191 APPLICATION - USE OF ANNEXE AS INDEPENDENT DWELLING
Approved
Erection of self contained "Granny Annexe" within rear garden
Approved
Construct an Annex/Summer/Work Room in Garden
24/289/CLEUD
Approved
Regularise the use of an annex as a house
Before you spend £2,000+ on drawings — and risk getting refused
Your council may refuse the exact thing that got approved two boroughs away. See what actually gets approved near your property first.
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