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Free 2026 London Planning ReportFlat Conversion Drawings in Brook Green W6

Kitchen extension planning drawings for a Victorian terrace in Brook Green W6, London Borough of Hammersmith and Fulham
Brook Green · W6 · Hammersmith & Fulham

Flat Conversion Drawings in Brook Green W6

Fixed-fee, MCIAT-chartered flat conversion drawings for Brook Green (W6) homeowners — London Borough of Hammersmith & Fulham validation and local constraints handled from the start.

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Brook Green in W6 is a sought-after enclave of large Victorian terraces and Edwardian mansion blocks in the green space between Hammersmith and Kensington. Families here typically extend at the rear or into the side return, convert generous lofts, or reconfigure mansion flats, so most of our drawings support space-making projects on characterful period homes.

The Brook Green conservation area and neighbouring designations mean roof alterations, front elevations and materials are all assessed against a strikingly consistent streetscape. We detail schemes to sit comfortably within that grain and present them the way Hammersmith and Fulham's officers expect, which keeps sensitive extensions and loft conversions moving smoothly towards approval.

Kitchen extension planning drawings for a Victorian terrace in Brook Green W6, London Borough of Hammersmith and Fulham
Isometric illustration of a Brook Green W6 home flat conversion drawings design
Proposed floor plan
Brook Green W6

Planning in Brook Green (W6): what to know before you apply

There is no published householder Article 4 direction we depend on for Brook Green, but the Brook Green conservation area constrains permitted development on roofs and principal elevations. Matching red-brick detail, respecting the scale of the terraces, and checking for protected street trees are the usual design limits on rear and roof works.

Typical Brook Green housing stock

Brook Green is a leafy pocket of large Victorian terraces and red-brick Edwardian mansion blocks set between Hammersmith and Kensington. The generous houses lend themselves to full-width rear extensions, side returns and loft conversions, while the mansion blocks generate careful internal reconfigurations and flat conversions that suit family life in W6.

Streets we regularly draw for in Brook Green

Yeldham Road · Winslow Road · Sussex Place · Playfair Street

What W6 is actually built of

Measured from 388 classified residential buildings in W6, not from a description of the area.

Brook Green W6 housing mix

Residential building form across the W6 postcode district, from 388 classified buildings.

Attached on more than one side80%
Attached on one side17%
Detached3%
Median building footprint63 m²
Addresses per buildingAbove about 2 means flats and maisonettes dominate2.68
Buildings classified388

Source: Ordnance Survey National Geographic Database (derived statistics). Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Extracted 2026-08-17.

Flat Conversion Drawings for Brook Green (W6) homes: the package and the process

Converting a house into flats is drawn unit by unit. Each proposed flat needs its layout, its floor area, its own entrance arrangement and its amenity provision shown, along with refuse and cycle storage that meets the standards the council applies to new residential units.

The separation between units is the technical core: floors and walls detailed for fire resistance and sound insulation, a common escape route drawn and protected, and services routed without breaching the compartments. Those details go on the drawings because Building Control assesses them there, not on site.

Conversion suits buildings with the plan depth and stair position to make two workable units. A wide terrace or a large semi can usually be split without landlocking a room, while a narrow plan often cannot give both units light, access and separation at the same time.

Do I need planning permission to convert a house into flats?

Yes, always. Converting a single dwelling into two or more self-contained flats is a change from one home to several, and that subdivision is treated as development requiring a full planning application — there is no permitted development route that allows it, regardless of the property's size or whether the exterior changes at all. The application has to demonstrate that each flat meets space, layout, amenity and parking standards in its own right, not just that the building as a whole is being used sensibly.

Boroughs also weigh the loss of a family-sized house against their local housing policy, since converting a larger house into several flats reduces the stock of homes suited to families even as it adds smaller units. We take that policy context into account when advising on layout and unit numbers, rather than simply maximising the number of flats the floor area could technically support.

What sound insulation is required between flats?

Part E of the building regulations sets minimum sound insulation standards for the walls and floors separating flats, covering both airborne and impact sound. Where an existing house is subdivided, the drawings specify how the party floors and walls between units will be upgraded — additional layers, resilient bars, or a floating floor — and pre-completion sound testing is normally required before the flats can be signed off. Getting this detail right on the drawings from the outset matters, because retrofitting sound insulation after a failed test usually means taking up a finished floor or ceiling that has already been decorated.

How do you design fire escape and compartmentation for flat conversions?

Each flat needs its own independent means of escape to a place of safety, and the building has to be compartmented so that fire in one flat does not spread into another or into the shared circulation space. On a typical converted house this means fire-rated floors, walls and doors between units, and either a protected common stairway shared by the flats or separate final exits for each one, depending on the layout.

Where flats sit above ground floor level, escape routes and fire doors are designed together with the sound insulation upgrade, since the same floor and wall build-ups often need to satisfy both requirements at once.

House-to-flats conversion drawing packages in London
ConversionTypical scopeRouteFee from
House to two self-contained flatsVertical split, separate or shared entranceFull planning plus building regulations£1,600
House to three or more flatsMultiple units, fire strategy requiredFull planning plus building regs plus structural£2,400
Flat conversion with a side or rear extensionAdditional floor area added to create compliant unitsFull planning plus structural calculations£2,800
Sheet from a flat conversion drawings package drawn for a Brook Green property in W6, showing the existing and proposed arrangement at scale
A sheet from the flat conversion drawings package we submit to London Borough of Hammersmith & Fulham for Brook Green (W6) properties.
FAQ

Flat Conversion Drawings in Brook Green W6 — FAQs

Do I need planning permission to convert a house into flats?+
Yes, always. Subdividing a single dwelling into two or more self-contained flats is treated as development in its own right, so a full planning application is required regardless of whether the exterior of the building changes.
How much do flat conversion drawings cost in London?+
Packages start from £1,600 for converting a house into two flats and rise to around £2,800 where three or more units, structural work or an extension are involved. We agree a fixed fee once we know the scope.
What sound insulation is required between flats?+
Part E of the building regulations sets minimum airborne and impact sound standards for the floors and walls separating flats, and pre-completion sound testing is normally required before the units can be signed off.
Does each flat need a separate fire escape?+
Each flat needs its own means of escape and the building needs to be fire-compartmented between units, using fire-rated floors, walls and doors and either a protected shared stairway or separate final exits.
What is the minimum size for a flat in London?+
London applies minimum internal floor areas based on bedroom and occupancy numbers, adopted from the national space standards through the London Plan. We check every proposed flat against the relevant threshold before drawing the layout.
Do I need planning permission for a side-return extension in Hammersmith & Fulham?+
On the Victorian and Edwardian terraces of Fulham and Shepherd's Bush a single-storey side-return or rear extension can fall within permitted development, so a full application isn't always required. Conservation areas across Fulham, Brackenbury and Ravenscourt Park, and the Peterborough Estate, restrict this. We check your street's designation first and can confirm permitted development with a Lawful Development Certificate.
Will I need a Basement Impact Assessment for a basement in Hammersmith & Fulham?+
Likely, yes. The council applies a basement policy requiring a basement impact assessment for below-ground works, covering structural stability, drainage and groundwater. Basement extensions are common on these terraces, so if you are considering one we flag the requirement early and coordinate the structural input so the application is complete when submitted.
What is special about the Peterborough Estate 'Lion houses'?+
The Peterborough Estate's distinctive red-brick 'Lion houses' carry strong conservation control over their external character, so alterations are expected to respect the estate's materials and detailing. We design to that character and prepare a full householder application where permitted development doesn't apply, which is the reliable route to approval there.
How long does Hammersmith & Fulham take to decide?+
The council determines most householder applications within the statutory eight-week period once validated; basement and conservation cases can involve additional consultation. Because the terraces are party-wall-sensitive, we prepare submissions to the borough's residential extension and basement guidance to avoid the drawing queries that cause most delays.
How much do planning drawings cost in Hammersmith & Fulham?+
We agree a fixed fee before we start, typically around 30% below an architect's fee for the same council-accepted drawings, with free redraws until the council approves. A side-return, a loft and a basement differ in complexity, so we quote once we have seen your address and project rather than by the hour.
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