Daylight & Sunlight Assessments
for London Planning.
daylight and sunlight assessments — VSC, APSH and NSL analysis — for planning applications across every London borough. Joining our service line in late August 2026 — enquire now to reserve an early slot.
We confirm the applicable BRE 209 criteria with your borough before modelling begins
A daylight assessment is not the same as a shadow diagram.
A shadow diagram tells you where a shadow lands. It doesn't tell you whether a window still gets enough daylight — that's a separate calculation, governed by BRE 209, and it's what London borough officers actually check before signing off amenity impact on neighbours. If your scheme is small enough that a shadow diagram alone will do, don't pay for more than you need: see Shadow Diagrams London, from £280.
Different tests, different decision-makers. BRE 209 is assessed by your borough as part of the planning application. Right to Light is a private property right between neighbours, built up over years, and no planning officer rules on it. Satisfying one says nothing about the other — if Right to Light is a live issue on your site, that's a conversation for a solicitor or Right to Light surveyor, not us.
What a BR 209 Daylight and Sunlight Assessment Can Include
One fixed price for your London submission. VSC, APSH and NSL calculated for every affected window, plus shadow diagrams, methodology statement and one free amendment — see the full deliverable breakdown on our UK page.
- ✓ VSC for all affected windows
- ✓ APSH for main living room windows
- ✓ NSL working plane analysis
- ✓ Shadow diagrams included
- ✓ Methodology statement (DAS-ready)
- ✓ One free planning amendment
27% VSC · 25%/5% APSH · 0.8× NSL
London boroughs apply BRE 209 (2022) with varying degrees of contextual flexibility for dense, historic urban areas — we confirm the applicable approach with your borough before commencing. For the full explanation of each metric, see our UK-wide BRE 209 reference.
Why London daylight assessments get sent back.
We've reviewed enough returned submissions to know the pattern. Three mistakes account for most of them.
- ✕A window gets left out
Ground floor flats, secondary bedrooms, side-return windows facing the site — these are the ones consultants forget, and London officers know to check for them. Leave one out and the whole submission goes back.
- ✕Numbers without a verdict
A table of VSC percentages means nothing to a duty planner unless it says, in plain terms, pass or fail against BRE 209. Boroughs increasingly refuse to do that cross-referencing themselves.
- ✕Guessed building heights
In London's terraced streets, a neighbour's roofline that's a metre out changes the VSC result. Assessments built on estimated heights rather than survey data don't survive scrutiny at appeal.
- ✓Window schedule agreed up front
Before modelling starts, we list every window in scope — ground floor, secondary rooms, the lot — and confirm it with you in writing.
- ✓Clear interpretation on every result
Each VSC, APSH and NSL figure is interpreted against the applicable BR 209 (2022) threshold — copy it straight into your DAS.
- ✓Real survey data, not guesswork
True north and neighbouring heights come from your survey or OS data. Referable schemes get flagged early so you're ready for GLA scrutiny too.
From brief to planning-ready BRE 209 assessment in four steps
Send Your Brief
Send your planning drawings, an OS map extract, and the name of the borough you're submitting to. That's enough for us to confirm the exact BRE 209 scope before anything is modelled.
Scope Confirmed in Writing
You get a written scope back — the full window list, which of VSC, APSH and NSL apply, and any quirks specific to your borough's validation checklist — before we touch the 3D model.
First Draft in 48 Hours
We build the model, verify it against OS data, and run VSC, APSH and NSL for every window in scope. Methodology statement included. First draft lands within 48 hours.
Final Report & Source Files
Once you've reviewed it and we've made any one round of changes, you get the final PDF, results tables and DWG source — formatted to go straight onto the Planning Portal.
Transparent pricing. No surprises.
Every quote is fixed price — not hourly. Invoiced in GBP. No VAT applicable.
Up to 10 windows assessed. VSC + APSH + NSL. Single planning application.
- VSC for all affected windows
- APSH for main living room windows
- NSL working plane analysis
- Shadow diagrams at equinox & solstice
- BRE 209 methodology statement
- Window-by-window interpretation against the applicable criteria
- 1 free planning amendment · NET 14
11+ windows, multi-storey development, or complex site geometry.
- Everything in Standard package
- Extended window schedule (11+)
- Multi-storey / complex geometry
- Appeal-quality methodology statement
- Referable-scheme presentation on request
- Priority 48-hour turnaround available
- Quoted per project scope
All prices in GBP. No VAT — invoiced from KAS STUDIO DOOEL, Skopje, North Macedonia. Fixed quotes within 24 hours of brief received.
All 33 London boroughs, plus the City and LLDC
Not listed here? Get in touch — we work with every London borough.
Common questions about BRE 209 daylight assessments in London
More questions on files, VAT, VSC/APSH/NSL definitions and turnaround? See the full FAQ on our UK page.
Also need just a shadow diagram, or coverage elsewhere?
Fixed-price quote within 24 hours.
- BRE 209 assessments from late August 2026
- Enquire now to reserve an early slot
- 48-hour first draft
- 1 free planning amendment included
- No VAT · NET 14 payment terms
Prefer to email directly? info@casstudio.com