Costs & Guides
Loft Conversion Planning Permission in Ealing
Most loft conversions in Ealing don't need planning permission. The ones that do are usually caught by something the owner didn't know applied to their street.
Two Separate Approvals
There are two separate approvals in play, and confusing them is the most common mistake people make.
Planning permission is about whether you're allowed to change the building's appearance and scale. Often you don't need it, because loft conversions can fall under permitted development.
Building regulations approval is about whether the work is structurally sound, safe and properly insulated. You need it on every loft conversion, without exception, whether planning permission is required or not.
Getting the first one right and skipping the second is the version of this that causes trouble years later, at the point of sale.
When a Loft Conversion Is Permitted Development
Roof enlargements — dormers, hip to gables, mansards — are covered by Class B of the permitted development rules. The allowance is a volume allowance, measured against the original roof space:
- 40 cubic metres for a terrace house
- 50 cubic metres for a semi-detached or detached house
Alongside the volume, all of these conditions have to be met:
- No part above the highest point of the existing roof.
- Nothing beyond the plane of the roof slope that fronts a highway — which is why front dormers almost always need an application.
- Materials similar in appearance to the existing house.
- The original eaves kept, with the enlargement set back at least 0.2 metres from them so far as practicable.
- No verandas, balconies or raised platforms.
- Side-facing windows obscure-glazed and non-opening unless the opening part is more than 1.7 metres above the floor.
Permitted development also does not apply to flats or maisonettes, or to a house created from a previous non-residential use through certain change-of-use routes.
Rooflights Are a Separate Class &Mdash; and It Matters
This is the distinction almost nobody explains, and in Ealing it's worth real money.
Roof enlargements (Class B) and other roof alterations (Class C) are governed by different rules. Rooflights and Velux-type windows fall under Class C, which permits them provided they protrude no more than 0.15 metres beyond the plane of the original roof slope, and no part sits above the highest part of the original roof. Class C carries the same obscure-glazing condition for windows in a side elevation.
Why this matters: Class B is not permitted on designated land — Class C carries no such exclusion. So in a conservation area, a dormer or hip to gable needs planning permission, while a flush rooflight conversion may still be permitted development.
Do not rely on that without checking your address, because an Article 4 direction can remove Class C as well — and in Ealing, at least one does.
Conservation Areas in Ealing
Ealing has 30 conservation areas, spread across Acton, Ealing, Hanwell, Northolt, NW10 and Southall. The council publishes an interactive map, and checking your address on it should be the first thing you do — before drawings, before quotes.
If your house is in one, roof enlargements are not permitted development. A dormer, hip to gable or mansard will need a planning application.
That is not the same as a refusal. Conservation area status changes the test, not the answer: the council is assessing whether what you propose preserves or enhances the character and appearance of the area. Rear dormers on streets where rear dormers already exist are approved regularly.
The Six Article 4 Areas &Mdash; and What They Remove
An Article 4 direction removes permitted development rights that would otherwise apply. Ealing has made directions covering six conservation areas, and several of them bite directly on loft conversions.
| Conservation area | What the direction removes |
|---|---|
| Bedford Park | The enlargement of a dwelling house by an addition or alteration to its roof and any other alteration to the roof. Both Class B and Class C. In Bedford Park, even rooflights need permission. |
| Churchfields — Half Acre Road | The enlargement of a dwelling house consisting of an addition or alteration to its roof |
| Ealing Town Centre — The Grove | Alterations to the dwelling including roof changes |
| Brentham Garden Estate | Alterations including replacement of roof materials |
| Hanger Hill Garden Estate | Alterations including roof materials |
| Hanger Hill (Haymills) Estate | Front elevation alterations and roof modifications |
Ealing Council's own wording is worth quoting on the point of tone: a direction “does not mean that the council will necessarily refuse permission, but enables it to exercise greater control in protecting the character and appearance of the conservation areas.”
So an Article 4 area isn't a closed door. It's a planning application where you'd otherwise not have needed one, with more attention paid to materials and detail.
Should You Get a Lawful Development Certificate?
If your conversion is permitted development, you don't legally need anything from the council. A Lawful Development Certificate is optional.
It's still usually worth having. An LDC is a formal document confirming the work is lawful, and the moment it earns its keep is at sale, when a buyer's solicitor asks what authority you had for the loft. “We were told it was permitted development” is a much weaker answer than a certificate.
A certificate for proposed development costs half the normal planning application fee. One for existing development — applied for after the fact — costs the same as a full planning application. Applying beforehand is both cheaper and simpler.
Building Regulations Apply Every Time
Separate consent, always required. The requirements that shape a loft conversion most:
- Structure. Existing ceiling joists hold up a ceiling, not a floor. New floor structure and, usually, steel beams.
- Fire safety. In a two-storey house, escape windows are not accepted — the existing stairway becomes the protected means of escape. Doors onto the stairs fire-rated to at least 20 minutes, a 30-minute fire-resisting new floor, and the stair discharging into a hall with a door directly outside.
- Smoke alarms. Mains-powered, interlinked, at every level.
- Stairs. A permanent staircase with at least 2 metres of headroom over the whole flight and landings — 1.9 metres may be accepted over part of it in some circumstances. A straight flight with landings top and bottom is the preferred form; space-saver or alternating-tread stairs are only permitted in exceptional circumstances.
- Insulation to current standards, in the roof and walls of the new room.
Completion produces a certificate. Keep it. It's the document that makes the loft a bedroom rather than a room a surveyor will describe as “additional space”.
What Is The &Ldquo;10 Year Rule&Rdquo;?
It comes up often enough to be worth answering properly.
Planning enforcement has a time limit. Under the Levelling-up and Regeneration Act 2023, which took effect on 25 April 2024, the previous four-year limit for building operations was removed and replaced with a single ten-year limit for all breaches of planning control. Work substantially completed before 25 April 2024 keeps the old four-year limit; work completed on or after that date falls under ten years.
Two things are worth saying plainly about it.
First, it's a longer wait than the folklore suggests. Much of what's repeated online still describes the four-year rule, which no longer applies to new work.
Second, and more to the point: enforcement isn't the real risk. Unauthorised work causes problems long before a council notices — at sale, when a buyer's solicitor finds no planning record and no building control certificate; at remortgage; and with insurers. The absence of a building regulations completion certificate is not cured by the passage of time at all, because building control and planning are separate regimes.
If you're worried about work already done, an LDC for existing development is the proper route, and a planning consultant or the council's own duty planner is the right first call — not a builder.
Three Things to Check Before You Design Anything
- Is your address in a conservation area? Ealing Council publishes an interactive conservation area map.
- Is it in one of the six Article 4 areas? If so, assume an application — and in Bedford Park, assume one even for rooflights.
- What's your volume allowance? 40 cubic metres for a terrace, 50 for a semi or detached — and remember it's measured against the original roof, so a previous extension may have used some.
This guide is general information about planning and building regulations in England and in the London Borough of Ealing. It is not planning advice and it isn't a substitute for it. Rules change, and how they apply depends on your specific property. Check your address with Ealing Council or take advice from a planning professional before committing to a design. We do not submit planning applications and we do not act as your agent.