Elegant London period townhouses of the kind found in Richmond upon Thames conservation areas

Richmond · London

Flat Conversion Drawings in Richmond

Fixed-fee, MCIAT-chartered flat conversion drawings for Richmond homeowners — London Borough of Richmond upon Thames validation and local constraints handled from the start.

Richmond upon Thames is one of London's most design-sensitive boroughs. A high proportion of its housing — Georgian and Victorian townhouses, Edwardian villas and riverside cottages — sits within conservation areas such as Richmond Green, Twickenham Riverside, Teddington, Kew Green and Barnes Green, and much of it lies within the Thames flood zone. Applications here succeed on the strength of careful, context-led drawings rather than standard templates, and permitted development cannot be assumed even for modest works.

The London Borough of Richmond upon Thames has some of the most extensive Article 4 coverage in London, with widespread directions removing permitted development rights across its conservation areas, plus basement and front-garden controls in parts of the borough. In practice that means alterations which would be automatic elsewhere — dormers, cladding, some rear works — need a full householder application here. Near the river in Twickenham, Richmond and Hampton, Thames flood-zone requirements apply, and protected views and river-frontage design control shape what is achievable, so we confirm the constraints for your exact address before drawing.

We prepare Richmond planning applications that respond to the borough's conservation and riverside setting, designing context-led drawings that reflect the period townscape and evidencing flood-risk and finished-floor-level considerations within the submission so the council can validate and approve without repeated revisions. The fee is fixed and agreed up front, typically around 30% below an architect's fee for the same council-accepted drawings, with free redraws until Richmond approves. Because so much turns on design detail, we prepare submissions to the validation checklist with the elevations and materials the council expects; conservation and riverside cases can attract additional consultation, but most householder applications are still determined within the statutory eight-week period, and our roughly seven-day drawing turnaround gets schemes moving quickly.

Proposed floor plan

Richmond

Planning in Richmond: what to know before you apply

Richmond has some of the most extensive Article 4 coverage in London, so permitted development cannot be assumed even for modest works — many conservation areas require a full application. Thames flood-zone considerations also apply near the river. We confirm the constraints for your exact address before drawing.

Typical Richmond housing stock

Georgian and Victorian townhouses, Edwardian villas and riverside cottages, many within conservation areas and close to the Thames.

Areas we regularly draw for in Richmond

Richmond · Twickenham · Teddington · Kew · Barnes · East Sheen · Hampton

What the numbers say about Richmond planning decisions

These are London Borough of Richmond upon Thames’s own reported figures, published by government rather than estimated by us. They are what we design against — a borough that refuses one householder application in five needs a different drawing package from one that refuses one in twenty.

Proving lawfulness in Richmond

Certificates of lawful development and prior-approval outcomes decided by London Borough of Richmond upon Thames over eight quarters.

Certificates of lawful development decided	913
Larger extensions cleared without a full application	0
Prior approval refused	46

Source: Ministry of Housing, Communities and Local Government (PS1 district planning application statistics). Open Government Licence v3.0 Extracted 2026-08-16.

If London Borough of Richmond upon Thames refuses: appeal outcomes

Planning appeals against London Borough of Richmond upon Thames determined by the Planning Inspectorate, 2021–2026. Enforcement notices and withdrawn cases are excluded.

Appeals determined	633
Allowed	243
Dismissed	390
Householder appeals allowedFrom 379 householder appeals. England average 36%	45%

Source: Planning Inspectorate appeals casework. Open Government Licence v3.0 Extracted 2026-08-16.

Flat Conversion Drawings for Richmond 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
Conversion	Typical scope	Route	Fee from
House to two self-contained flats	Vertical split, separate or shared entrance	Full planning plus building regulations	£1,600
House to three or more flats	Multiple units, fire strategy required	Full planning plus building regs plus structural	£2,400
Flat conversion with a side or rear extension	Additional floor area added to create compliant units	Full planning plus structural calculations	£2,800

Sheet from a flat conversion drawings package prepared for a Richmond property, drawn to London Borough of Richmond upon Thames validation standards — A sheet from the flat conversion drawings package we submit to London Borough of Richmond upon Thames.

Local Areas

Flat Conversion Drawings across Richmond

Also in Richmond

Planning Permission Planning Drawings Architectural Drawings Building Regulations Drawings Loft Conversion Drawings Flat Conversion Drawings across London

FAQ

Flat Conversion Drawings in Richmond — 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 an extension in Richmond?+

More often than in most boroughs, yes. Richmond has some of the most extensive Article 4 coverage in London, so permitted development cannot be assumed even for modest works — many conservation areas such as Richmond Green, Teddington and Kew Green require a full application. We confirm the exact designation for your address first and design accordingly rather than relying on permitted development.

My Richmond home is near the river — does flood risk affect my application?+

It can. Much of the borough lies within the Thames flood zone, and the council expects flood-risk considerations to be addressed for works near the river in Twickenham, Richmond and Hampton. We evidence flood-risk and finished-floor-level considerations within the application so the council can validate and approve without repeated revisions.

What does Richmond's Article 4 coverage mean in practice?+

Article 4 directions remove permitted development rights across many of Richmond's conservation areas, so alterations that would be automatic elsewhere — dormers, cladding, some rear works — need a full householder application here. We design context-led drawings that respond to the borough's period townscape and river frontage, which is what carries an application to consent in Richmond.

How long does Richmond Council take to decide?+

Richmond determines most householder applications within the statutory eight-week period once validated, though conservation and riverside cases can attract additional consultation. Because so much turns on design detail here, we prepare submissions to the validation checklist with the elevations and materials the council expects, to avoid drawing queries.

How much do planning drawings cost in Richmond?+

We agree a fixed fee before starting, typically around 30% below an architect's fee for the same council-accepted drawings, with free redraws until Richmond approves. Conservation and flood-zone cases require more evidence than a standard extension, so we quote once we understand your address and scheme rather than by the hour.

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Tell us your Richmond address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.