A typical brief
A growing family in a 1930s semi-detached house in Northfields, Ealing, needs a fourth bedroom and a larger kitchen. They want one project rather than two: a two-storey rear extension with a single-storey infill of the side passage, built in one contract.
Constraints and planning context
A two-storey rear extension can be permitted development only if it is no more than 3 m deep and at least 7 m from the rear boundary; the side infill would also need separate assessment. The cleanest route is a single householder planning application. Ealing looks closely at first-floor rear extensions: the 45-degree test from the neighbour’s nearest first-floor window, subordinate roof forms, and a step in from the shared boundary at first floor.
How we would design it
The ground floor extends 4 m across the full width, with the side passage infilled to make a kitchen-dining room. Owners usually want the first floor at 3.5 m deep and hard against the party boundary, and that is exactly what Ealing’s officers push back on. We would draw it at 3 m and set 1 m in from the boundary from the outset, with a hipped roof matching the original, and include a 45-degree diagram showing the neighbour’s window unaffected.
Likely planning route
A householder planning application decided within the statutory 8 weeks, with conditions on materials the normal outcome for a first floor that clears the 45-degree line. The application fee is £528 (verify before applying). The Building Regulations package follows, coordinating steelwork with the structural engineer.
Documentation we would prepare
- Measured survey and existing drawings
- Proposed plans, elevations and sections
- 45-degree daylight diagrams
- Householder planning application and officer liaison
- Building Regulations drawings and specification, 3–5 weeks after approval
Read more about our house extensions, householder planning applications and Building Regulations drawings, see how we work in Ealing, or get an instant estimate.
