The 3-Meter and 6-Meter Rear Extension Rules

1. The PDR Geometry Matrix

When executing a Full Refurbishment of an unlisted terraced house in the London Borough of Hammersmith & Fulham (LBHF), the most commonly utilized Permitted Development Right (PDR) is the single-storey rear extension. However, navigating the strict mathematical limits dictates whether you need formal planning permission.

2. The 3-Meter "As of Right" Limit

Standard PDR dictates that on an attached terraced house, you can extend outwards by a maximum of 3 meters from the original rear wall of the house. You cannot exceed 4 meters in overall height (or 3 meters at the eaves if within 2 meters of the boundary). If the Architecture team keeps the design within these exact boundaries, and uses matching materials, you can secure an LDC and bypass the planners.

3. The "Original Rear Wall" Trap

Clients frequently miscalculate the 3 meters. You must measure from the "Original Reall Wall" as it stood in 1948, or when the house was built. If a previous owner in 1980 already built a 2-meter rear extension, you cannot add another 3 meters onto it. You only have 1 meter of PDR remaining. Attempting to build a further 3 meters will trigger devastating Planning Enforcement action.

4. The 6-Meter "Larger Home Extension"

To stimulate the economy, the government introduced the "Larger Home Extension" scheme, supposedly allowing terraced houses to extend up to 6 meters deep. However, this is not automatic PDR. You must undergo a "Prior Approval" process with the Planning Directorate.

5. The Prior Approval Neighbor Veto

In the Prior Approval process, LBHF planners do not assess the aesthetics; they simply write to your immediate neighbors. If a neighbor objects (citing loss of light or feeling "boxed in"), the 6-meter PDR right is instantly suspended. The council then fully assesses the application against the strict LBHF Local Plan policies for deep extensions, which frequently results in refusal.

How We Can Help

If you are considering a major refurbishment, extension or basement in Hammersmith & Fulham, our in-house architectural and construction teams are highly experienced with the specific constraints and policies of LBHF. Do not leave your planning application to chance—our Planning & Permissions and Architecture services are explicitly designed to handle strict London authorities from initial conceptual design through to final, legal consent.

Once permission is secured, our Refurbishment & Interiors division carefully manages the execution, guaranteeing the design integrity is maintained throughout the build phase.

*Published in the Hampstead Renovations Planning Guide Collection — delivering expert design and build strategies for London's most heavily guarded conservation boroughs.*