Daylight and Sunlight Assessments in Bexley

Bexley is a borough of 1930s semis with generous gardens, and most of what we assess here starts life as one of them: a side extension and a raised roof in Sidcup or Blackfenn to turn a three-bedroom house into something bigger, a two-storey rear extension in Bexleyheath or Barnehurst, or a loft conversion with a side dormer that brings a new window close to the neighbour's. The other recurring job is the parade of shops with flats above, on Upper Wickham Lane, Welling High Street, Bellegrove Road and the Broadway, where an upward extension has to be shown not to harm the flat next door, often without any drawings of that flat to work from.

Bexley's planning officers work from the Local Plan adopted in 2023 and the council's Design Guide SPD, and they are consistent about two things: they want the effect on neighbouring windows tested to the BRE guidance, and where a scheme creates new homes they want to see that those homes, including any loft rooms, get adequate daylight themselves. The two recent jobs below show both sides of that. Our main daylight and sunlight assessment page explains what goes into a report.

Recent daylight and sunlight assessments in Bexley

13-14 Christopher Close, Sidcup, DA15: neighbours and loft rooms assessed from one model

The scheme raised the ridge of a semi-detached house by around a metre, added side and rear extensions and a loft conversion with a side dormer, and provided two additional self-contained flats. The homeowner and planning consultant needed two questions answered: the effect on ten surrounding houses, and whether the new loft bedrooms would be adequately daylit. From one 3D model we ran the BRE tests on the neighbouring windows and gardens and the internal daylight tests on the new rooms.

The application, 25/02444/FUL, was granted with conditions on 23 April 2026.

Upper Wickham Lane, Welling: flats above a shop, and a neighbour with no floor plans

The scheme extends the flats above a shop on Upper Wickham Lane, with the second-floor rear element redesigned as a mansard. The architect needed to show no adverse effect on the adjoining property, which had no reliable floor plans, so we used its earlier planning drawings as evidence of the layout. One first-floor window fell below the VSC guideline, but it was one of two serving the same bedroom, and assessed together using the BRE weighted-window method the room met the guidelines. The report concluded no adverse daylight effect on the adjoining property, and the application is now being prepared with it.

What Bexley planning officers look for

Bexley's approach to daylight and sunlight is set by the Bexley Local Plan, adopted in April 2023. Policy DP11 on high-quality design requires all development to provide appropriate levels of privacy, outlook, natural daylight and other amenity, and to protect the amenity of existing properties, while Policy D19 addresses daylight and sunlight to outdoor amenity space. Officers apply the BRE guidance BR 209: Site layout planning for daylight and sunlight (2022 edition).

For householder schemes, Bexley's Design Guide SPD, and in particular its Building Alterations and Extensions guidance, sets out how those policies are applied to extensions, roof alterations and loft conversions. You can find the Local Plan at bexley.gov.uk/development-plan and the supplementary planning documents at bexley.gov.uk/supplementary-planning-documents-and-guidance. In our experience Bexley officers read the room-by-room tables, not just the summary, so we set out which windows serve habitable rooms, which were discounted and why.

When you need an assessment in Bexley

• Raised ridges, hip-to-gable conversions and side dormers on the 1930s semis of Sidcup, Blackfenn, Welling and Barnehurst, where the new roof sits over the neighbour's flank windows
• Two-storey side and rear extensions in Bexleyheath, Crayford and Bexley village that bring a flank wall closer to a neighbour's rear windows
• Upward extensions to flats above shops on Upper Wickham Lane, Bellegrove Road, Welling High Street and the Broadway
• Conversions that create new flats or loft rooms, where Bexley will want to see the new rooms are adequately daylit
• New houses on garden and backland plots in Erith, Belvedere and Slade Green with neighbours on more than one side
• Any scheme where a neighbour has raised loss of light or the case officer has asked for a BRE assessment

How we work

We build a 3D model of the proposal and its surroundings from your drawings, mapping data and photographs, with no need to enter the neighbouring property, then run the BRE tests on every window and garden that could be affected. The fee is fixed and agreed up front, and the report usually takes 4–5 working days from final drawings. If something falls short we tell you first and model the fix. The four tests are:

• Vertical Sky Component (VSC): how much sky a neighbouring window can see
• No-Sky Line (NSL), or daylight distribution: how far daylight reaches into the room
• Annual Probable Sunlight Hours (APSH): annual and winter sunlight to windows within 90 degrees of south
• Sun on ground: whether at least half of a garden still gets two hours of sun on 21 March

See our VSC, NSL and APSH page for how each test works and our BRE guidelines page for the thresholds.

Frequently asked questions in Bexley

The flat next to my shop has no plans on file. Can you still assess it?

Yes. We use the council's planning records, mapping, photographs and the building's own layout to establish which windows serve habitable rooms, and where there is doubt we test more than one interpretation and say so in the report, as we did on Upper Wickham Lane.

Does Bexley want the loft bedrooms tested as well as the neighbours?

Where the scheme creates new homes, yes: Policy DP11 asks for adequate natural daylight in the new accommodation as well as protection for existing properties. Both assessments can come from one model, which keeps the cost down.

Does Bexley test gardens?

It can. Policy D19 covers daylight and sunlight to outdoor amenity space, so where a two-storey extension or raised roof sits to the south of a neighbour's garden we include the sun-on-ground test.

Get a fixed-fee quote

Send your drawings through our contact page or use the price calculator for an instant figure. Call Nick on 01962 809155 or email nick@sunlightassessments.co.uk. For sites on the Greenwich side of the border, see our Greenwich page.