Row of yellow-brick terraced houses with slate porch canopies, brightly painted front doors and small front gardens behind low brick walls and railings, with plane trees along the pavement

SM4 · Morden · Merton

Planning and building regulation drawings in Morden (SM4)

Morden's older core sits around St Lawrence Church and Church Farm Cottage near London Road, a small historic group. Most of the housing that surrounds it came later: late-Victorian and Edwardian homes, the cottages and villas of the John Innes estate with their hedged front gardens and distinctive detailing, and interwar suburban streets spreading toward the town centre. Dorset Road, Kingston Road, London Road, Central Road and Mostyn Road are among its roads.

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London Borough of Merton granted 92% of 769 householder applications
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That mix means two homeowners in the same postcode can face very different rules. In the southern streets that fall within the John Innes conservation area at Merton Park, Merton has long used Article 4 directions to remove permitted development rights, so changes to doors, windows, boundary walls and roofs need an application rather than a quick check against the usual limits. It is a far tighter regime than most London conservation areas apply, reaching from a replacement window to a loft.

Away from those streets, the interwar suburban housing raises the ordinary questions. A rear extension, side addition or loft conversion with a rear dormer is checked against the permitted development limits, and Merton expects extensions to respect the consistent building lines of the interwar roads. The Upper Morden conservation area protects the church group, so anything nearby is considered for its effect on that setting.

Conversion is a separate question. Merton has made an Article 4 direction on turning a family home into a small house in multiple occupation, and it is understood to cover Morden, though it may apply only in designated wards, so we confirm the position for your address. We check the conservation boundary, the direction maps and the listing for your exact address before drawing anything.

Planning in Morden: what to know before you apply

Merton judges householder work on its design and its fit with the street, and it controls materials, rooflines and front elevations most tightly in its conservation areas. In the John Innes streets the Article 4 directions mean even small external alterations are applications, and in any conservation area roof enlargements, side extensions and rear extensions of more than one storey fall outside permitted development. Elsewhere in Morden, rear extensions and lofts on interwar houses can often be dealt with as permitted development if they stay inside the limits, which is why we confirm the position before drawing. Flats have no householder rights at all. Separately, where the HMO direction applies, a change of use to a small HMO, meaning three to six unrelated sharers, needs planning permission.

Applications are decided by London Borough of Merton — its planning pages.

Check your route

Does your Morden project need planning permission?

Route check · Morden (SM4)

ProjectProperty

Listed building?

Conservation area?

Likely permitted development — no planning applicationNeeds checking

A single-storey rear extension up to 4 m deep on a detached house, or 3 m on any other house, is Class A permitted development subject to the height and materials conditions.
An Article 4 direction applies here and may withdraw this freedom — the schedule must be checked before relying on it.
One or more constraints are unknown — we check the council's registers as part of the free appraisal.
Where permitted development applies, a lawful development certificate proves it for lenders and buyers.

Sources: GPDO 2015, Schedule 2, Part 1 · Planning Portal — common projects · Building Regulations 2010 — when approval is needed

This is a first-pass indication from the national rules, not planning advice for your property. Your council's registers, any Article 4 schedule and the exact dimensions decide it — the free appraisal checks all three before we recommend a route.

Confirm it with a free appraisal

Morden (SM4) in numbers

What London Borough of Merton has decided, and what SM4 is built of — the two facts that shape every job here.

Householder planning decisions — London Borough of Merton

Morden (SM4) applications are decided by London Borough of Merton; these are its published householder figures for the last four quarters.

Householder applications decided2025 Q2 to 2026 Q1	769
Granted	709
Refused	60
Grantedof 769 decisions · England 90%	92%
Decided within 8 weeksof 499, excluding prior approvals	88%

Source: Ministry of Housing, Communities and Local Government (PS2 district planning application statistics). Open Government Licence v3.0 Extracted 2026-09-22.

Permitted development prior approvals — London Borough of Merton

How the larger-home-extension route has fared with London Borough of Merton, which decides SM4 notifications.

Larger home extension prior approvals — not required2024 Q2 to 2026 Q1	321
Prior approval granted	40
Prior approval refused	179
Grantedof 219 determined	18%

Source: Ministry of Housing, Communities and Local Government (PS1 district planning application statistics). Open Government Licence v3.0 Extracted 2026-09-22.

Planning appeals — London Borough of Merton

Refusals in SM4 can be appealed to the Planning Inspectorate; this is London Borough of Merton's householder appeal record.

Householder appeals determined2021–2026	116
Allowed	41
Allowedof 116 · England 36%	35%

Source: Planning Inspectorate appeals casework. Open Government Licence v3.0 Extracted 2026-09-22.

Conservation areas and Article 4 directions — London Borough of Merton

Register counts for London Borough of Merton. A count describes what the council has published, never a rank against another council.

Conservation areas in the register28 dated, 1968–1997	28

Source: MHCLG Planning Data Platform. Open Government Licence v3.0 Extracted 2026-09-22.

What SM4 is built of

Residential building form across Morden (SM4), from 274 classified buildings — the fact that decides party walls, side returns and loft headroom before any policy does.

Attached on more than one side	55%
Attached on one side	42%
Detached	3%
Median building footprint	56 m²
Addresses per buildingAbove about 2 means flats and maisonettes dominate	1.11
Buildings classified	274

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 2026-09-22.

Day 0Measured survey of your Morden property — or your existing plans if you have them.
About 7 daysDrawings issued for your approval. Free redraws until you are happy.
SubmissionWe validate against London Borough of Merton’s checklist and submit on your behalf.
Council: 8-week targetHouseholder applications carry an 8-week statutory target. London Borough of Merton decided 88% of 499 recent householder applications inside it.

Source: Ministry of Housing, Communities and Local Government (PS2 district planning application statistics). Open Government Licence v3.0 Extracted 2026-09-22.

Neighbourhoods

Streets and neighbourhoods in SM4

Mordenpredominantly late-Victorian and Edwardian

Nearby

Nearby postcode districts

Cheam SM3Carshalton SM5Belmont SM2Wallington SM6Sutton SM1

FAQ

Morden (SM4) — FAQs

Can I change the windows or front wall on a John Innes street in SM4?+

Probably not without permission. The Article 4 directions on the estate remove the rights that would normally cover those changes, so windows, doors, boundary walls and roofs facing the street need a planning application. Like-for-like repair is a different matter, and we can tell you where the line falls for your house.

Can I turn my Morden house into a small HMO?+

Not without planning permission where the direction applies. Merton's Article 4 direction removes the right to convert a family home to a small HMO, and it is understood to cover Morden; we confirm it for your address. If you only want to let a room to one or two lodgers, that is a separate question, and we can talk it through before any drawings.

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