020 7864 7245Request a fixed quote

Hounslow, London

Daylight and sunlight report in Hounslow

Hounslow's full-planning validation checklist sets a standard in plain words: a daylight and sunlight assessment must show no unacceptable loss of amenity to adjacent occupiers. The method it names is the BRE guide, cited as BRE (list cites 2011 edition). This page explains how a study answers that sentence, and when a smaller scheme can get by without one.

Fixed quote after a free constraints check

  • MCIAT chartered
  • £2m PI insured
  • LABC Partnered
  • Fixed fees, VAT included

Request a fixed quote

We use it to check conservation areas and constraints.
Pick the council that decides your application.
A few lines: what you want to build, and anything the council has already said.
Add photos or drawings

Drop files here or choose from your device

PDF, JPG, PNG, DWG · up to 10 files, 90 MB in total

    Architectural model of a four-storey London stucco townhouse in its terrace, with a portico, area railings, sash windows, a cornice and chimney stacks
    The house as it stands: four storeys over a lower ground floor.Existing Proposed worksAn illustrative model, built for this page.

    How we work on daylight and sunlight reports

    Seven steps from first call to approval.

    The same model cut through the middle: every floor, the stair, the chimney breasts, the new mansard, rear extension and basement in section
    Section through the model: every floor on one datum.

    1. Enquiry and constraints check

      We check the property against conservation areas, listed status, Article 4 directions, tree preservation orders, flood zone and planning history. We choose the right route and send a fixed quote.

    2. Measured survey

      We survey the house on one datum: rooms, levels, boundaries, drains, trees and the neighbours' windows that the 45° and 25° tests depend on.

    3. Design options

      We model the house in Revit and show you options in 3D and plan, with the planning strategy and the precedents in your street.

    4. Design frozen

      You choose an option in writing. Nothing changes after this without your say.

    5. Independent check

      A second chartered technologist checks every sheet against the council's validation checklist and the policy. A senior review signs it off before anything is submitted.

    6. Submission

      We prepare the forms, certificates, fee and documents and submit through the Planning Portal.

    7. Officer liaison

      We answer the planning officer and make any amendments within five working days, at no charge until approval.

    Free redraws until approval. Every drawing set is checked independently, and the checker is never the person who drew it.

    Request a fixed quote
    Rear view of brick terraced houses in London with slate roofs and chimney stacks along the shared roofline

    The test in Hounslow's own words

    The checklist for full applications, major or minor, asks that the assessment show no unacceptable loss of amenity to adjacent occupiers. It must follow the BRE guide, examine existing properties and sites with extant permissions, and report the final values within the proposed scheme. The document is undated and refers to an earlier year in its text, so look for a newer version before you rely on it.

    The phrase unacceptable loss is the important one. The BRE guide is advisory and sets guideline values, not a legal limit; the word unacceptable implies some loss may be tolerable. A good report therefore reports the figures and also argues why the loss is, or is not, acceptable in this setting.

    We write the conclusion to answer that sentence directly, so the officer can see the council's own test being applied.

    Pencil resting on a dimensioned technical drawing beside a scale rule

    Local figures for Hounslow

    Figures with their unit, period and source
    MeasureValuePeriodSource
    A daylight and sunlight assessment must show no unacceptable loss of amenity to adjacent occupiers, follow the BRE guide (the checklist cites the 2011 edition), examine existing properties and sites with extant permissions, and report final values within the proposed scheme.BRE (list cites 2011 edition)—hounslow.gov.uk, Hounslow Validation Checklist, Full planning (major or minor) (undated; refers to November 2019), pdf pp.9-10, row 'Sunlight / Daylight Assessment'
    Conservation areas33 named conservation areas published by the council—planning.data.gov.uk
    Article 4 directions3 Article 4 directions published by the council—planning.data.gov.uk
    Listed building entries519 list entries (Historic England, within the LPA boundary)—planning.data.gov.uk
    worldHeritageSites1 World Heritage Sites intersecting the LPA boundary—planning.data.gov.uk
    Households living in a house54 % of households living in a house or bungalow (detached, semi-detached or terraced)Census 2021nomisweb.co.uk
    Average price, terraced611,320 GBP2026-07publicdata.landregistry.gov.uk
    Householder decisions689 decisions1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications granted78.5 %1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications decided in time97.8 % decided within 8 weeks or an agreed extended period1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Minor applications granted72.4 %1 July 2025 - 30 June 2026assets.publishing.service.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 Hounslow
    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

    A borough with very different streets

    Hounslow runs from dense town-centre blocks around the main roads to suburban streets near the green spaces. 54 per cent of households live in a house or bungalow, and 45.7 per cent own their home. The split matters because the weight a council gives to light loss varies with context, and a flat above a shop is judged differently from a family semi.

    Terraced houses averaged £611,320 and detached houses £1,043,294 in the latest figures. At those values, a neighbour objecting about light has a strong reason to follow the case closely.

    Heritage that sets the height

    Historic England lists 519 entries in Hounslow, including 32 at Grade I, and the borough contains 1 World Heritage Site. It also has 33 conservation areas and 3 Article 4 directions. A scheme near any of these may have its height or roof form fixed by the setting, which limits the options for easing a light problem.

    When the height is fixed, the report carries the weight. We set out the tests we ran on alternatives, so the council sees that the chosen form is the least harmful that the setting allows.

    Design codes and plan policy

    For design, the council's reference is the Character, Sustainability and Design Codes SPD, which sits under the Hounslow Local Plan 2015-2030 (Volumes 1 and 2). The plan was adopted in 2,015, so the borough's own policy is older than the current London-wide guidance on light.

    In practice we cite both: the borough's design code for the form of the extension, and the Mayor's guidance for the flexibility officers may apply. That pairing gives the report two anchors.

    Timing and the householder record

    Hounslow decided 689 householder applications in the latest published year and granted 78.5 per cent. It decided 97.8 per cent in time. Minor schemes were granted at 72.4 per cent from 312 decisions.

    Not every householder case is granted, so a thin application has less room for error than a complete one. A prepared light study is one of the ways to complete it.

    Sequencing the work

    We build the study after the design has been surveyed and the massing settled, but before the drawings are finalised. That order keeps any change cheap. If the first results are marginal, we test a lower eaves line, a shallower depth or a stepped roof in the model, and show you the effect of each on the neighbour's windows. You then choose the option with the best balance of space and light, and the drawings follow that choice.

    Where to go from here

    The wider guide to daylight and sunlight reports sets out the tests. For the drawings, see planning drawings in Hounslow, and for the borough overview, architectural drawings in Hounslow. Neighbouring lists differ, so compare Richmond upon Thames and Ealing.

    We fix the fee after a free look at the site.

    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.
    Rows of brick terraced houses and gardens on a residential street
    The street around you
    Move across the plinth — the blocks rise around the pointer.

    Other services in Hounslow

    Daylight and sunlight reports nearby

    Questions

    What does Hounslow mean by unacceptable loss of amenity?

    The checklist does not give a number. The study follows the BRE guide, cited as BRE (list cites 2011 edition), and the officer judges the result in context.

    Does a World Heritage Site affect my scheme?

    The borough contains 1 World Heritage Site, and nearby heritage can fix height and roof form, which limits how a light problem can be fixed.

    Is the checklist up to date?

    It is undated and refers to an earlier year, so check the council's website for a newer version before you apply.

    Which design code applies?

    The Character, Sustainability and Design Codes SPD, under the Hounslow Local Plan 2015-2030 (Volumes 1 and 2).

    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.

    Request a fixed quoteCall 020 7864 7245WhatsApp