Garage in Barnet: Planning Permission Guide
A guide to building a garage in Barnet under permitted development — rules, costs, and professional advice.
Based on 51 decided applications in Barnet over 12 months (37 granted, 14 refused).
Barnet has over 15 conservation areas including Hampstead Garden Suburb — a unique 1907 planned community with its own Trust exercising very strict design controls alongside council powers. Other notable conservation areas include Totteridge Village, Mill Hill, and Monken Hadley. The northern fringe borders substantial Green Belt around Totteridge and Arkley. Article 4 Directions cover parts of Hampstead Garden Suburb and other heritage streets.
Recent garage decisions in Barnet
The 5 most recent decided applications. Addresses redacted to postcode area.
New garage with 1no. rooflight adjacent to existing garage. Replacement, widening and repositioning of existing hard standing of front dr…
Conversion of the existing garage into habitable room, insertion of window to replace garage door
Conversion of the existing garage into habitable room, insertion of bay window to replace garage door
Conversion of the existing garage into habitable room including insertion of window and door to replace garage door, alterations to the r…
Conversion of the existing garage into habitable room, insertion of window and a door to replace garage door. Alterations to the rear of …
These are borough-wide. See the 5 nearest to your address.
Check your address freePermitted Development Rules
Buildings etc incidental to the enjoyment of a dwellinghouse
GPDO 2015, Schedule 2, Part 1, Class E
Garages fall under Part 1, Class E of the GPDO (the same class as outbuildings). They must be incidental to the enjoyment of the house.
Key dimension limits
These are the maximum GPDO limits for a detached house with no constraints. Your actual limits depend on your property type, location, and any planning restrictions.
Enter your postcode to see the personalised limits for your garage.
Check my limitsTypical Costs in London
Garage costs depend on size, whether it's attached or detached, and whether it includes electrics or additional rooms above.
Cost per m²
construction rate
Typical total
Based on 15–20 m²
Typically includes
Typically excludes
Single garage. Double garages and garages with rooms above will be significantly more.
Get a personalised cost estimate based on your actual garage dimensions.
Get my estimateWhich Professionals Do You Need?
A standard single garage can often be built from supplier designs. A garage with rooms above will need architectural and structural input.
A draughtsperson or architectural technician can prepare any drawings needed. A full architect may not be necessary.
Garden buildings and garages can often use supplier designs or simple drawings from a draughtsperson.
Typical fee: £500–£2,000 (Basic drawings)
A structural engineer may be needed if the garage has a room above or connects to the house.
Typical fee: £500–£1,500
May apply if the work is within 3 metres of a shared boundary. Check with your builder.
Typical fee: £700–£1,500 (per neighbour (if applicable))
This guidance is based on a typical semi-detached house with no special constraints. Listed buildings, conservation areas, and attached properties may require additional professional input.
Find out exactly which professionals you need for your garage.
Get personalised guidanceConservation Areas & Listed Buildings
In conservation areas, garages are subject to the same Class E rules. Consider using materials sympathetic to the area character.
Properties in conservation areas often have reduced permitted development rights. Some project types (like side extensions) lose PD rights entirely. An Article 4 Direction can remove additional PD rights.
Listed buildings (Grade I, II*, or II) have no permitted development rights at all. Any external alteration requires Listed Building Consent in addition to any planning permission. An architect experienced in heritage work is essential.
Check if your property is in a conservation area or has other planning constraints.
Check my propertyFrequently Asked Questions
Just want a quick yes/no for your garage?
Run our free 2-minute check to see whether your project likely qualifies as permitted development in Barnet — your address, your constraints, your council's own recent decisions.
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