Single-storey rear extension onto a garden behind an interwar semi-detached house in Collier Row RM5 in the London Borough of Havering

Collier Row · RM5 · Havering

Rear Extension Drawings in Collier Row RM5

Fixed-fee, MCIAT-chartered rear extension drawings for Collier Row (RM5) homeowners — London Borough of Havering validation and local constraints handled from the start.

Collier Row (RM5) took shape as an interwar suburb of Romford, expanding through the 1920s and 1930s across former Essex farmland. It is a planned residential district rather than a historic village core, with predominantly semi-detached housing, so almost every householder project here is an extension or loft on one of those consistent interwar pairs.

There is no conservation area covering Collier Row — that is a genuine, verified fact, not an omission. Its planning character is instead shaped by the uniformity of its interwar suburban roads and by the London Borough of Havering's householder design expectations, which favour keeping the semi-detached rhythm, the gaps between pairs and the original materials intact. We treat that suburban cohesion, rather than a conservation designation, as the reference point when we design an extension.

Demand for rear extensions, two-storey side extensions and hip-to-gable lofts is steady across roads like Mawney Road, Silvermere Avenue and Victoria Avenue, where regular plots and gardens are typical. We check each property's permitted-development position against Havering's borough-wide controls first, then prepare drawings that either stay within permitted development or are ready to validate as a full householder application.

Proposed floor plan

Collier Row RM5

Collier Row (RM5) — planning at a glance

Council: London Borough of Havering
Postcode district: RM5
Planning portal: View the Havering planning portal
Housing stock: Predominantly interwar semi-detached houses on planned suburban roads, with postwar and modern infill on regular gardened plots. The consistent pairs and generous front and rear gardens are what makes rear extensions, side extensions and hip-to-gable loft conversions the common projects here.
Article 4: No area-specific Article 4 direction is published for Collier Row; the London Borough of Havering's borough-wide permitted-development controls and householder design guidance still apply.
Sample streets: Collier Row Road · Lodge Lane · White Hart Lane · Clockhouse Lane · Mawney Road · Lawns Way · Mashiters Hill · Carter Drive · Ravenswood Close · Hunter's Grove · Silvermere Avenue · Victoria Avenue
Local constraints: Consistent interwar semi-detached street pattern, so front-elevation changes, roof forms and the gap between pairs are assessed against a cohesive suburban rhythm rather than a one-off houseHavering's borough-wide permitted-development limits and householder design guidance govern extension depth, height and coverage — no local Article 4 direction narrows them further in Collier RowMatching original facing brick, render, tile-hanging and roof tiles so a rear or side addition reads as part of the original interwar pair rather than an obvious bolt-onThe characteristic gap between semi-detached pairs, which the council protects so streets do not close up — this shapes how wide a two-storey side extension can be and whether it must be set back and set downRegular but finite plot and garden sizes, which constrain how deep a single-storey rear extension can go before it needs a full householder applicationShared party walls and building lines between paired houses, making party-wall relationships, overshadowing and neighbour amenity relevant to what gets approved

Planning in Collier Row (RM5): what to know before you apply

Because Collier Row's suburban roads repeat so consistently, Havering assess extensions against the established semi-detached pattern, so matching original brick, render and roof form and preserving the gap between pairs matters more than on a mixed-typology road. There is no conservation area and no local Article 4 direction, so many houses retain permitted development rights for rear and loft work — but the finite gardens and shared building lines mean depth, height and neighbour impact are the points a householder application is judged on.

Typical Collier Row housing stock

Predominantly interwar semi-detached houses on planned suburban roads, with postwar and modern infill on regular gardened plots. The consistent pairs and generous front and rear gardens are what makes rear extensions, side extensions and hip-to-gable loft conversions the common projects here.

Streets we regularly draw for in Collier Row

Collier Row Road · Lodge Lane · White Hart Lane · Clockhouse Lane · Mawney Road · Lawns Way · Mashiters Hill · Carter Drive · Ravenswood Close · Hunter's Grove · Silvermere Avenue · Victoria Avenue

Rear Extension Drawings for Collier Row (RM5) homes: the package and the process

Every rear extension drawings we prepare for an Collier Row property is drawn to London Borough of Havering’s validation standards and tuned to the RM5 constraints above. Here is what the drawing package covers and how the process runs from first survey to approval.

A single-storey rear extension is the most common way London homeowners add space, usually taking the form of an open-plan kitchen-diner that opens onto the garden through bi-fold or sliding doors, with rooflights or a roof lantern bringing daylight deep into the plan. Because depth and height are tightly controlled by permitted development rules and by the 45-degree rule that protects neighbouring windows, the design work sits as much in checking what the council will allow as in drawing what you want.

DrawingsDirect draws rear extensions for permitted development, the larger home extension prior-approval scheme and full householder planning, with structural calculations for the opening and roof produced in-house by our MCIAT-chartered team. If your project also involves widening the kitchen sideways or adding a second storey, see our Side Return, Wraparound and Double Storey Extension pages — many London rear extensions grow into one of those during design.

Do I need planning permission for a rear extension in London?

Many single-storey rear extensions qualify as permitted development, meaning no planning application is needed, provided depth, height and materials stay within set limits. That changes if your property sits in a conservation area or is subject to an Article 4 direction, both of which can remove permitted development rights across a street or borough — in that case a full householder planning application is required regardless of size.

Even where an extension qualifies, most homeowners obtain a Lawful Development Certificate to confirm that status in writing before building — useful for mortgage lenders, buyers and Building Control. We check your property against your borough's constraints before recommending a route.

How deep can a single-storey rear extension go?

Depth is the main constraint on a rear extension, and it depends on your house type and whether you use standard permitted development or the larger home extension scheme.

Permitted development

Standard permitted development allows a single-storey rear extension up to 3 metres deep for terraced and semi-detached houses, or 4 metres for detached houses, generally with eaves height limited to match or stay close to the existing house.

Larger home extension scheme

The prior-approval scheme extends this to 6 metres for terraced and semi-detached houses and 8 metres for detached houses. Your council writes to affected neighbours; if none object within the notification period, approval follows without a full planning application. If an objection is raised, the council assesses the impact on neighbouring light and outlook itself, rather than automatically refusing, so a well-considered design still has a good chance of approval.

Rear extension routes at a glance
Route	When it applies	Typical fee
Permitted development (Lawful Development Certificate)	Depth within 3m (terraced/semi) or 4m (detached), height and materials within PD limits	PD/LDC pack ~£950–£1,450
Larger home extension (prior approval)	Depth up to 6m (terraced/semi) or 8m (detached), with neighbour notification	from £1,100
Full householder planning permission	Extension exceeds PD/larger-home limits, or the property is in a conservation area with an Article 4 direction	Full Planning pack ~£1,600–£2,400
Planning + Building Regulations (structural)	Combined planning and construction-ready pack with structural calculations for the opening and roof	Planning + Building Regs pack ~£2,200–£3,850

Also in Collier Row RM5

Planning Permission Planning Drawings Architectural Drawings Building Regulations Drawings Loft Conversion Drawings Rear Extension Drawings across Havering Rear Extension Drawings across London

FAQ

Rear Extension Drawings in Collier Row RM5 — FAQs

How much does a rear extension cost to design in London?+

Rear extension drawings start from £1,100, with the final fee set by the route your extension takes — permitted development, prior approval or full planning — and whether you need building regulations and structural calculations bundled in. The fee is fixed and agreed upfront.

Do I need an architect for a rear extension?+

No. DrawingsDirect is an MCIAT-chartered architectural technologist practice, producing the same council-accepted drawings as an architect for a fixed fee typically around 30% lower.

How long does it take to get rear extension drawings?+

Drawings are typically ready around 7 days from survey. Once submitted, councils have a statutory 8-week period to determine a standard householder planning application.

What is the 45-degree rule?+

It is a daylight test many London councils apply to check that a rear extension does not block too much light to a neighbour's nearest window, measured as a line drawn at 45 degrees from that window. We check it before submission, not after a refusal.

Will I need a Party Wall Agreement for a rear extension?+

Only if your foundations or new walls sit on or near the boundary with a neighbouring property. A straightforward rear extension set within your own plot often does not trigger the Party Wall etc. Act 1996, unlike a Side Return or Wraparound extension, which usually does.

Do I need planning permission to extend a house in Collier Row?+

Not always. Many Collier Row semis retain permitted development rights, so a modest single-storey rear extension or a hip-to-gable loft conversion can often proceed without a full planning application. Because the plots are regular but finite and the gap between pairs is protected, we check your property's size limits and building lines against Havering's controls first, and prepare a full householder application where the project goes beyond permitted development — as a two-storey side extension often will.

Is Collier Row in a conservation area?+

No. There is no conservation area covering Collier Row. Its planning character is shaped instead by its uniform interwar semi-detached suburban roads and Havering's householder design expectations, which favour keeping the semi-detached rhythm, the gaps between pairs and the original materials intact when you extend.

How much do planning and building-regulation drawings cost for a Collier Row extension?+

We work to fixed fees agreed before we start, with a typical turnaround of around seven days for a standard rear extension, side extension or loft on a Collier Row semi. As a chartered architectural technologist practice we produce the same council-accepted planning and building-regulation drawings as an architect, usually for a lower fee, and include free redraws until your application is approved.

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