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Merton, London

Lawful Development Certificate in Merton

A Lawful Development Certificate in Merton gives a house owner written proof that an extension or loft needs no planning application, and in a borough where 60.4 per cent of households live in a house, many owners qualify. Our drawings and submission start at £645 including VAT.

From £645 (VAT included)

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  • LABC Partnered
  • Fixed fees, VAT included

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We use it to check conservation areas and constraints.
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    Brick cottage with a tiled roof, chimneys and a front dormer window

    Heritage that limits Merton's permitted development

    Merton has 28 conservation areas, and in each of them the national rules rule out side extensions and cladding and cap rear extensions at one storey. The designation is the main reason a house in Merton may not qualify, so we check it before anything else.

    Historic England records 243 list entries in the borough. A listed house needs consent of its own, and a certificate cannot stand in for it. If the certificate route closes, the council's Borough Character Study guides the planning decision you then face, though it changes nothing about what the national rules allow.

    Government returns record 58 lawful development certificate applications for Merton in the latest twelve months published. That is a modest volume, so a clear, well-measured application stands out.

    Rows of brick terraced houses and gardens on a residential street

    Local figures for Merton

    Figures with their unit, period and source
    MeasureValuePeriodSource
    Conservation areas28 named conservation areas published by the council—planning.data.gov.uk
    Listed building entries243 list entries (Historic England, within the LPA boundary)—planning.data.gov.uk
    Households living in a house60.4 % of households living in a house or bungalow (detached, semi-detached or terraced)Census 2021nomisweb.co.uk
    Lawful development certificate applications (PS1)58 certificates2025 Q2 to 2026 Q1 (1 Apr 2025 to 31 Mar 2026)assets.publishing.service.gov.uk
    Larger home extension prior approvals granted22 decisions2025 Q2 to 2026 Q1 (1 Apr 2025 to 31 Mar 2026)assets.publishing.service.gov.uk
    Larger home extension prior approvals refused80 decisions2025 Q2 to 2026 Q1 (1 Apr 2025 to 31 Mar 2026)assets.publishing.service.gov.uk
    Householder decisions759 decisions1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications granted92.9 %1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications decided in time85.2 % decided within 8 weeks or an agreed extended period1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    GPDO 2015 Sch 2 Pt 1 Class A, para A.1(f)(i)3 m (attached) / 4 m (detached) beyond the original rear wall, single storey—legislation.gov.uk
    Class A, para A.1(b)Buildings (other than the original house) may not cover more than 50% of the curtilage—legislation.gov.uk
    Class A, para A.2On article 2(3) land (conservation areas etc.): no side extensions, no cladding, no rear extension of more than one storey under Class A—legislation.gov.uk
    DMPO 2015 art 39(10)(a)8 weeks—legislation.gov.uk
    Lawful Development Certificate: proposed use or operationHalf the normal planning fee (householder: £274)—ribblevalley.gov.uk

    A blank value means the figure has not been published, not that there are none. Check your own address with the council.

    Councils bordering Merton
    Which application your project needsLawful Development Certificate decision: 8 weeks. Prior approval decision: 42 days. Householder decision: 8 weeksYour projectWithin permitted development?Lawful Development CertificatePrior approvalHouseholder applicationYesLarger rear extensionNoABC

    Which application your project needs

    The usual route for a house; flats and listed buildings follow other rules.

    A · Lawful Development Certificate decision
    8 weeks
    B · Prior approval decision
    42 days
    C · Householder decision
    8 weeks

    Terraces, semis and the size of the project

    Land Registry figures put the average terraced house in Merton at 686,591 and the average semi-detached house at 954,064. The plot behind each type differs, and so does the project an owner can fit inside the national limits.

    That variation matters for the limits. Large plots meet the half-curtilage cap rarely, small ones meet it quickly once a previous extension and a shed are counted. Detached houses use the longer rear depth limit; terraces and semis use the shorter one. We measure each plot and apply the right test, rather than quoting a generic allowance.

    How Merton's deeper-extension record compares

    When an owner wants a rear extension beyond the standard depth, larger home extension prior approval is the route. In the latest twelve months Merton granted 22 and refused 80. Refusals outnumber grants by a wide margin, so for many owners a design inside the standard limits, confirmed by a certificate, is the safer plan.

    We set the options side by side at quote stage: what a certificate confirms, what prior approval might add and what each costs in time. Read more at prior approval drawings in Merton.

    Timing in Merton and the planning fallback

    The statutory period for a certificate is 8 weeks, though a request for information pauses it. Merton decided 759 householder applications in its latest published year and granted 92.9 per cent, but only 85.2 per cent were decided in time. That is a planning figure, not a certificate one, yet it is worth knowing if your project may need to move to householder planning.

    The fee table reads: Half the normal planning fee (householder: £274). Our planning drawings in Merton cover the fallback.

    Lawful Development Certificate in Merton: the evidence we gather

    A certificate application rests on a measured survey and a record of the original house. We collect historic mapping, dated photographs, earlier planning decisions and the plot boundaries, because the coverage and eaves limits both depend on them.

    Larger plots mean the survey covers more ground than on an inner London terrace. We record the house, every later addition and each outbuilding, and total them against the plot area so the officer can check the sum in one look. Where a previous extension was built without paperwork, we establish whether it is lawful, since it still counts. Send us any earlier decisions, completion certificates and survey reports and we will use them to shorten the survey. The same file helps later if you sell, because a buyer's solicitor will ask for it. We keep a copy of the file with the job record.

    What the fixed fee covers

    You receive existing and proposed plans, elevations, a section where height matters and the location and block plans. A second chartered technologist checks each sheet before submission, and we redraw free until approval if the council asks for changes. The fee starts at £645 including VAT, agreed before work begins.

    For the full service list, see architectural drawings in Merton. Next door the rules differ in Sutton and Wandsworth.

    What you receive

    Planning drawing sheet for a rear extension with plans, elevations and sections
    Sample drawing. Planning drawings for a rear extension: plans, elevations and sections on one sheet set.
    Rear view of brick terraced houses in London with slate roofs and chimney stacks along the shared roofline
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    Other services in Merton

    Lawful Development Certificates nearby

    Questions

    Is my Merton house in a conservation area?

    Merton has 28 conservation areas. We check the council's map at quote stage, because inside one the rights are cut back.

    Can I extend further than the standard depth in Merton?

    Possibly through prior approval, though Merton granted 22 and refused 80 in the latest twelve months. We advise before you choose.

    How long does Merton take to decide a certificate?

    The statutory period is 8 weeks, subject to information requests.

    What does a certificate cost in Merton?

    The fee table reads: Half the normal planning fee (householder: £274). Our fixed fee starts at £645 including VAT.

    Do large Merton plots make a certificate easier?

    Often, because the half-plot cap is harder to reach on a big garden. The depth, height and eaves limits still apply in full, and we measure each of them from the original house.

    Sources and dates

    City of London skyline glowing at dusk across the Thames under a dramatic orange sky

    Tell us about your property.

    We check the constraints, then send a fixed fee. Messages before 3pm get a reply the same working day.

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