Daylight & Sunlight Assessments
for Birmingham Planning.
daylight and sunlight assessments — VSC, APSH and NSL analysis — for planning applications across Birmingham, from Edgbaston extensions to high-rise regeneration schemes in Digbeth and Eastside. Joining our service line in late August 2026 — enquire now to reserve an early slot.
We confirm the applicable BRE 209 criteria with your council before modelling begins
A daylight assessment is not the same as a shadow diagram.
A shadow diagram shows where shadows fall. A BRE 209 daylight and sunlight assessment quantifies exactly how much daylight and sunlight reaches specific windows and spaces — and compares those figures against BRE 209 thresholds. Birmingham planning officers use these results to assess amenity impact on neighbours; shadow diagrams alone are not sufficient for most major Birmingham applications. Need a shadow diagram only? See Shadow Diagrams Birmingham — from £280.
A BRE 209 daylight/sunlight assessment is a planning matter, decided by your council. Right to Light is a separate civil law matter between neighbouring landowners and isn't decided by the planning authority. We prepare planning-stage BRE 209 reports — for Right to Light, we'll point you to a solicitor or Right to Light surveyor.
What a BR 209 Daylight and Sunlight Assessment Can Include
One fixed price. Everything your Birmingham planning application requires. No extras, no revision charges.
VSC Calculated for All Affected Windows
Vertical Sky Component calculated for every affected neighbouring window identified in your council's brief. Results reported as absolute value and percentage of former value, with results and interpretation against the 27% threshold and 20% reduction rule.
APSH Analysis
Annual Probable Sunlight Hours calculated for main living room windows facing within 90° of south. Annual and winter (September–March) figures reported separately, with window-by-window interpretation against the applicable criteria.
NSL Working Plane Analysis
No Sky Line analysis of affected rooms, showing the proportion of the working plane (at 0.85m) receiving direct skylight before and after the proposed development, compared against the 0.8× threshold.
Shadow Diagrams at Required Dates
Shadow footprints at the equinox (21 March / 21 September) and winter solstice (21 December) at all required time-points. Existing and proposed shadows distinguished by colour — included as part of every assessment.
BRE 209 Methodology Statement
Written methodology confirming software and sun-path model, OS grid reference, applicable BRE 209 section, reference dates, and true north basis. Written for planning officers — ready to paste into your DAS.
One Free Planning Amendment
If your council requests amended daylight calculations as a planning condition, one amendment round is included at no additional charge — reviewed, updated and re-issued within 48 hours.
The three BRE 209 daylight and sunlight metrics
BRE 209 (Site Layout Planning for Daylight and Sunlight, 2022) is the primary guidance document used by Birmingham boroughs. These are the three main assessment criteria.
Measures the proportion of the sky vault visible from the centre of a window. A VSC of 27% or more generally indicates adequate skylight.
If a proposed development reduces a neighbouring window's VSC by more than 20% of its former value, the impact may be noticeable. Both the absolute value and the reduction are reported.
BRE 209 §2.2Measures the hours of direct sunlight a window receives over the year. Main living room windows facing within 90° of south should receive at least 25% of APSH annually, including 5% in winter (21 Sept–21 March).
BRE 209 §3.2Divides a room's working plane (at 0.85m) into areas that can and can't receive direct skylight. If the daylit area falls below 0.8 times its former value, occupants typically notice the reduction.
BRE 209 §2.3BRE 209 thresholds are guidance, not mandatory standards. Birmingham boroughs apply them with varying degrees of contextual flexibility. We confirm the applicable approach with your council before commencing.
Why daylight assessments get challenged at planning.
The same issues appear repeatedly in Birmingham planning officer comments and appeal decisions. We eliminate all three before submission.
- ✕Windows Omitted from the Assessment Scope
Assessments that omit windows which should have been included — typically ground floor windows, secondary rooms, or elevations not facing the development — can require a full re-assessment once identified.
- ✕No interpretation against the applicable threshold
Presenting results in tabular form without interpretation against the applicable BR 209 (2022) criteria is insufficient for most Birmingham planning applications. Officers need to read the assessment without cross-referencing the BR 209 text themselves.
- ✕Geometry not verified against OS data
Assessments built from approximate building heights or unverified geometry are challengeable at appeal — especially in dense inner-Birmingham terraces where a few degrees changes the result.
- ✓Full window schedule confirmed before modelling
We confirm the full schedule of windows to be assessed — including ground floor, secondary rooms and all affected elevations — before modelling begins. Scope agreed in writing.
- ✓Window-by-window interpretation, referenced to BR 209 (2022)
Every VSC, APSH and NSL result includes interpretation against the applicable threshold, referencing the specific BR 209 (2022) section. Ready to paste into your DAS without modification.
- ✓OS-Verified Geometry & Methodology Statement
True north, building heights and neighbouring footprints verified against OS data or survey. Schemes in the Big City Plan area flagged early so the contextual flexibility case can be presented clearly to the council.
From brief to planning-ready BRE 209 assessment in four steps
Send Your Brief
Share your planning drawings, OS map extract, borough name and any specific requirements from the validation checklist. We confirm the required BRE 209 criteria and window schedule before starting.
Scope Confirmed in Writing
We confirm the full window schedule, applicable BRE 209 sections (VSC, APSH, NSL), reference dates, and any council-specific requirements in writing before modelling begins.
First Draft in 48 Hours
3D model built and verified against OS data. VSC, APSH and NSL calculated for all windows in scope. BRE 209 methodology statement prepared. First draft delivered within 48 hours.
Final Report & Source Files
After review and one amendment round, final print-ready PDF, results tables and DWG source files delivered — ready for direct upload to 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.
Birmingham City and the West Midlands
Not listed here? Get in touch — we work with every Birmingham borough.
Common questions about BRE 209 daylight assessments in Birmingham
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