Daylight and Sunlight Assessments in Haringey

Haringey's housing stock is tight. The Victorian terraces of Harringay, Hornsey and Crouch End, the Edwardian streets of Muswell Hill and the converted houses of Tottenham and Wood Green all put a neighbour's rear window within a few metres of any extension, and the borough's backland sites, from mews plots behind Hornsey High Street to former yards off Green Lanes, are often hemmed in on three sides. That is where internal daylight to the new rooms becomes the issue, rather than light to the neighbours.

Officers here apply Policy DM1 of the Development Management DPD, which asks for appropriate sunlight and daylight both for neighbours and for future occupiers, so our daylight and sunlight assessments in Haringey are as likely to be internal studies of a new mews house as neighbour studies of a terrace extension. Two recent examples are below.

Recent daylight and sunlight assessments in Haringey

98 High Street, Hornsey, N8 7NT: a new mews house hemmed in on every side

A two-bedroom mews house to the rear of 98 High Street, Hornsey. Two of its rooms could only be lit from walls facing a small enclosed garden, and on the first run both fell well short of the BRE 209 (2022) daylight target. Testing layout and glazing options found a combination that worked without enlarging the rear window: one bedroom trimmed from 2.6 to 2.5 metres wide, the rooflight taken to its maximum size, and a letterbox window replaced by two windows that suited the main building. All other rooms met the guidelines.

Haringey approved the application with conditions on 22 July 2025 under reference HGY/2024/2879.

21a Coniston Road, Muswell Hill, N10 2BL: ground-floor rear extension to a flat

A single storey rear extension to a ground-floor flat in Muswell Hill, where confirmation was wanted that the neighbours' windows either side would not be unduly affected. We ran VSC, NSL and APSH to every neighbouring window; every window tested met the BRE guidelines, so no design change was needed.

The report was issued while the application was being determined, and the application, reference HGY/2026/0134, was approved with conditions on 13 August 2026.

What Haringey planning officers look for

Haringey determines applications against its Local Plan, made up of the Strategic Policies (adopted March 2013) and the Development Management DPD (adopted July 2017), alongside the London Plan. The council has been reviewing its development management policies, but the 2017 DPD remains the adopted basis for decisions.

The policy that governs daylight and sunlight is DM1, Delivering High Quality Design. It expects development to secure a high standard of amenity for both future occupiers and neighbours, including appropriate sunlight, daylight and open aspect to all parts of the development and to adjacent buildings and land. In practice an applicant is expected to show that a scheme does not significantly worsen the light already enjoyed by surrounding homes and gardens, and that new homes will themselves be adequately lit. Haringey has no single borough-wide extensions SPD; much of the householder guidance sits in the DPD, supplemented by area documents such as the House Extensions in South Tottenham SPD and the conservation area appraisals, which are read with DM1 where they apply. The technical benchmark is BRE 209: Site layout planning for daylight and sunlight (2022 edition).

The Local Plan is at haringey.gov.uk/planning-building-control/planning/planning-policy/local-plan, the Development Management DPD at haringey.gov.uk/.../local-plan-development-management-dpd and the supplementary planning documents at haringey.gov.uk/.../supplementary-planning-documents-spds.

When you need an assessment in Haringey

• A new mews house or backland dwelling behind Hornsey High Street, Green Lanes or Tottenham High Road, where the rooms are lit from a small enclosed courtyard and DM1 requires adequate internal daylight
• A rear extension to a terrace in Harringay, Hornsey or Crouch End, or to a flat in Muswell Hill, where a neighbour's kitchen or living-room window is close to the new wall
• A house extension in the South Tottenham SPD area, where the council's own extension guidance applies on top of DM1
• A basement or lower-ground conversion where the main living space has limited external wall and needs rooflights or larger windows to reach the daylight target
• A flatted scheme or additional storeys around Wood Green, Tottenham Hale or Seven Sisters, where both neighbours and new homes are tested
• Any application where a Haringey officer has raised light at pre-application or validation stage

How we work

Nick Maslen scopes each job, agrees a fixed fee up front and tells you whether the council will want a neighbour study, an internal study or both. Milica or Ana then builds the 3D model and runs the BRE 209 tests, usually within 4–5 working days of receiving the information we need. Where a room or window falls short we test options, as at Hornsey, and show you the smallest change that resolves it before anything is written up. The four neighbour tests are:

• VSC (Vertical Sky Component): the sky still visible from each neighbouring window
• NSL (No-Sky Line): daylight distribution within each neighbouring room
• APSH (Annual Probable Sunlight Hours): annual and winter sunlight to windows within 90 degrees of south
• Sun on ground: the share of a garden receiving two hours of sun on 21 March

Internal daylight to new homes is tested on the daylight provision method in BRE 209 (2022). The tests are explained on our VSC, NSL and APSH page and the thresholds on our BRE guidelines page.

Frequently asked questions in Haringey

Does Haringey ask for an internal daylight report on a backland house?

Frequently, because DM1 covers future occupiers as well as neighbours. Where rooms are lit from an enclosed courtyard, we recommend testing early: at Hornsey the solution was a 100 millimetre change to one room, a larger rooflight and a different window arrangement, all cheaper to draw before the application than after.

Is a rear extension to a Muswell Hill or Crouch End flat likely to need a report?

Not every one, but where the extension runs along a boundary close to a neighbour's rear window the council may ask, and a short neighbour study, as at Coniston Road, is a quick way to settle it.

Can I find my report on Haringey's planning register?

Yes. Haringey's register is a search-based system, so look up the application reference and the daylight and sunlight report will be listed among the documents.

Get a fixed-fee quote

Send drawings and the address through our contact page or use the price calculator for an instant figure; Nick is on 01962 809155 and nick@sunlightassessments.co.uk. For sites north of the North Circular, see our Enfield page.