PLANNING CONSULTANTS · HOUNSLOW
Planning consultants in Hounslow
We prepare and coordinate the planning case and specialist reports for sites in Hounslow covering Chiswick, Brentford, Isleworth, Hounslow, Feltham and Cranford. This page sets out what London Borough of Hounslow asks for when you apply, with links to the council's own documents.
THE COUNCIL'S DOCUMENTS
What Hounslow
judges you against.
Validation list. Hounslow local validation requirements - application-type checklists (Full Planning Application (Major and Minor); Householder; Change of Use) (Consulted on 14 October-29 November 2019; no adoption or effective date shown on the checklists). An application missing a required document can be made invalid, which delays the decision.
This list dates from 2019, before the London Plan 2021 and statutory biodiversity net gain, so the national and London requirements apply as well. Our validation review confirms the current position.
Development plan. Hounslow Local Plan 2015-2030 (Volume 1) (adopted, 2015); Hounslow Local Plan 2015-2030 (Volume 2) (adopted, 2015); Hounslow Local Plan Review 2020-2041 (under examination; hearings closed 2 July 2026; post-hearing consultation to 29 Oct 2026) (emerging, 2026).
National policy. The National Planning Policy Framework and, for every London council, the London Plan 2021 sit alongside the local plan.
LOCAL PLANNING POINTS
Things that shape applications in Hounslow.
Checked against the council's published policy and guidance. Each point links to its source.
- Single-storey rear extensions are limited to 3.05m deep on terraced houses, 3.65m on semi-detached and 4.25m on detached houses (Residential Extension Guidelines, May 2024). Source
- Full-width box dormers are normally refused; dormers must be set in from the ridge, eaves and sides, by at least 1m on larger houses. Source
- A borough-wide Article 4 direction has required planning permission for small HMOs since 4 September 2023. Source
- HMOs are expected within a 400m walk of town centre facilities and in areas with good public transport (HMO SPD, 2017). Source
- Additional HMO licensing applies borough-wide from 11 December 2025. Source
- Article 4 direction: Small HMOs. Changing a house (C3) to a small HMO (C4) needs planning permission across the borough, except open land, industrial areas, Chiswick Business Park, Bedfont Lakes Business Park and Mogden Sewage Works. Source
- Article 4 direction: Commercial to residential and demolition for new homes. Changing commercial, business and service (Class E) premises to homes (Class MA), and demolishing and rebuilding certain office, industrial or flat blocks as homes (Class ZA), in town centres, neighbourhood centres, strategic and locally significant industrial sites and key office locations. Source
- 2 further Article 4 directions apply to particular areas or conservation areas. Council list
REPORTS HOUNSLOW ASKS FOR
Hounslow's validation list, report by report.
Which of these your application needs depends on the project and the site. In Hounslow, extra reports are triggered most often by a conservation area, flood zones 2 and 3, flood3, large sites, air quality management areas, close neighbours. Enter the address in our application checker to see the list for your site.
| Report | Level | When it is needed | Policy |
|---|---|---|---|
| Construction Environment Management Plan | Required | Required for all major developments.Applies to: major schemes | Hounslow Air Quality Action Plan 2018-2023 |
| Energy Statement | Required | Required for all new-build development and all major schemes, following GLA energy guidance.Applies to: one new home, 2 to 9 homes, major schemes, commercial | GLA energy assessment guidance |
| Health Impact Assessment | Required | Required for 10+ homes or 1,000 sqm+ commercial; a rapid HIA (HUDU tool) up to 99 homes/9,999 sqm, with a comprehensive HIA likely above that.Applies to: major schemes | Source |
| Planning Statement | Required | Expected with full and change-of-use applications, describing the site and proposal and justifying any policy non-compliance (a cover letter listing documents is the minimum fallback).Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | Source |
| Air Quality Statement/Assessment | Where relevant | Should confirm whether air quality is an issue and set out mitigation where poor air quality could affect future occupiers.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | Hounslow draft Air Quality SPD (2013) |
| Tree Survey | Where relevant | For householder schemes, needed where a TPO tree or a tree in a conservation area would be felled.Applies to: house extensions | Source |
| Design and Construction Method Statement | Where relevant | Required for major developments and any development (including householder) that creates a basement, covering traffic, dust, noise, vibration and stability.Applies to: major schemes, basements, house extensions | Mayor's Sustainable Design and Construction SPG |
| BREEAM pre-assessment | Where relevant | Needed within the energy submission where a BREEAM Excellent rating is required.Applies to: major schemes, commercial | Source |
| Land Contamination Assessment | Where relevant | Needed where the site has a history or potential of contamination, prepared by a competent qualified person.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | Hounslow Contaminated Land Strategy |
| Sunlight/Daylight Assessment | Where relevant | Needed where the scheme could cause unacceptable loss of daylight or sunlight to adjacent occupiers, also showing levels within the scheme.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | BRE guidance (2011) |
| Design and Access Statement | Where relevant | In a conservation area, needed where the scheme creates 100 sqm+ of floorspace or one or more dwellings (householders included).Applies to: house extensions, one new home, 2 to 9 homes, commercial, changes of use, basements | DMPO 2015 Art. 9 |
| Draft Heads of Terms (planning obligations) | Where relevant | Needed where planning obligations are required to make the development acceptable.Applies to: major schemes, 2 to 9 homes, commercial | Hounslow Planning Obligations and CIL SPD |
| Nature Conservation and Ecological Assessment | Where relevant | Needed where the site is in a nature conservation area or could affect protected species.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | Source |
| Financial Viability Assessment | Where relevant | Needed where the applicant argues policy requirements (e.g. affordable housing) cannot be met; a full un-redacted appraisal is required and will be published.Applies to: major schemes, 2 to 9 homes | Source |
| Flood Risk Assessment | Where relevant | Needed for all new development in Flood Zones 2 and 3 and for sites of 1 ha+ in Flood Zone 1.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | NPPF |
| Environment Agency Flood Risk Matrix (householder) | Where relevant | For householder schemes in Flood Zones 2/3, needed where the proposal is a basement or ground-floor extension.Applies to: house extensions, basements | EA standing advice |
| Listed Building and Conservation Area Appraisal | Where relevant | Needed for works to a listed building within a conservation area.Applies to: all applications | Source |
| Historical and Archaeological Assessment | Where relevant | Needed where the site lies within an Archaeological Priority Area; small-scale fieldwork may be required.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | Source |
| Landscape plans and planting schedule | Where relevant | Required for all major schemes and for minor schemes that significantly change garden areas.Applies to: major schemes, 2 to 9 homes, one new home | Source |
| Lighting Assessment | Where relevant | Needed for publicly accessible schemes with external lighting near homes, listed buildings, conservation areas or open countryside.Applies to: major schemes, commercial, changes of use, 2 to 9 homes | Source |
| Noise Impact Assessment | Where relevant | Needed where the development may disturb neighbours or where existing noise could affect future occupiers.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | Hounslow/Hillingdon/Richmond noise SPD; BS8233; BS4142 |
| Dynamic thermal modelling (overheating) | Where relevant | Needed where there is an overheating risk, such as single-aspect homes facing south or west.Applies to: one new home, 2 to 9 homes, major schemes | Source |
| Parking survey | Where relevant | Needed with the transport submission in low-PTAL areas, near stations or near town centres that are outside a Controlled Parking Zone.Applies to: 2 to 9 homes, major schemes, commercial, changes of use | Source |
| Retail / Office / Employment Assessment | Where relevant | Needed for loss of town-centre retail, out-of-centre retail of 500 sqm+ (other town centre uses 2,500 sqm+), or loss of B1/B2/B8 space with 1-2 years' marketing evidence.Applies to: changes of use, commercial, major schemes, 2 to 9 homes, one new home | NPPF |
| Road Safety Audit | Where relevant | Needed where any change to vehicle access is proposed.Applies to: one new home, 2 to 9 homes, major schemes, commercial, changes of use, basements | Source |
| Statement of Community Engagement | Where relevant | Needed for large-scale major applications where pre-application community consultation is expected.Applies to: major schemes | Source |
| Flood risk and drainage information | Where relevant | Major and some minor applications need drainage calculations, infiltration feasibility, the drainage hierarchy and a maintenance plan (plus the council drainage form).Applies to: major schemes, 2 to 9 homes, one new home, commercial, changes of use, basements | London Plan SI13 |
| Transport Assessment and Travel Plan | Where relevant | Needed where the scheme generates significant extra traffic or parking demand or reduces parking; single dwellings are excluded.Applies to: 2 to 9 homes, major schemes, commercial, changes of use | London Plan; NPPF |
OUR SERVICES IN HOUNSLOW
Every report, one coordinated team.
All 54 services are available for sites in Hounslow. Prices are starting estimates; we confirm the fee in writing before appointment.
Planning & strategy
Heritage & townscape
Water & ground
Environment & amenity
Ecology & landscape
Energy & sustainability
Transport & viability
Structure, basements & ground
- Structural feasibility notes
- Structural planning statements
- Basement impact assessments
- Basement construction method statements
- Ground movement assessments
- Groundwater & hydrology screening
- Geotechnical desk studies
- Ground investigation reports
- Slope stability assessments
- Retaining wall assessments
- Demolition & construction method statements
- Construction management plans
- Structural reuse & retrofit appraisals
- Structural condition discharge statements
Neighbouring councils
YOUR QUESTIONS ANSWERED
Planning in Hounslow: FAQs
Still have a question?
Tell us about the site and we will confirm what Hounslow will need and what it should cost.
Make an enquiryWhich reports does Hounslow require for a house extension?
Hounslow's list adds reports mainly when the site has constraints, such as a conservation area, flood zones 2 and 3, flood3, large sites, air quality management areas, close neighbours. Drawings and the forms are always needed. Our application checker lists the reports for your address.
How up to date is Hounslow's validation list?
The list we use is "Hounslow local validation requirements - application-type checklists (Full Planning Application (Major and Minor); Householder; Change of Use)", dated Consulted on 14 October-29 November 2019; no adoption or effective date shown on the checklists. Councils revise their lists, so we confirm the current version before you commission reports.
Do you cover every part of Hounslow?
Yes. We work across the whole of Hounslow, including the postcode districts TW3, TW4, TW5, TW7, TW8, TW13, TW14, UB2, W4 and areas such as Chiswick, Brentford, Isleworth, Hounslow, Feltham and Cranford.
Where are you based?
Our office is at Unit D New Wave House, 4 Humber Road, London NW2 6DW, and we work on sites across all 32 London boroughs, the City of London and OPDC.
YOUR NEXT STEP
Planning an application in Hounslow?
Tell us about the site and what you want to build. We will tell you which reports Hounslow is likely to need and what they should cost.
Call 020 8004 4464 or email info@greencodeconsultants.com.