If you are planning a house extension, a new home or a larger residential scheme in Chorley, understanding the local daylight requirements in Chorley will help your application run smoothly. Chorley Council is the local planning authority (LPA) for the borough – Lancashire County Council does not determine householder or residential planning applications here. This guide sets out the adopted policy position and how daylight and sunlight are assessed in practice.
Daylight requirements in Chorley: the policy framework
Chorley sits within the Central Lancashire planning area, so the adopted development plan is made up of two documents working together:
- The Chorley Local Plan 2012-2026, adopted in 2015, which allocates sites and sets development management policies; and
- The Central Lancashire Core Strategy, adopted in 2012 and shared with Preston and South Ribble, which sets the strategic vision and design objectives to 2026.
The policies most relevant to daylight, sunlight and overshadowing are:
- Core Strategy Policy 17 (Design of New Buildings), which requires development to protect the amenity of neighbours, including in relation to overlooking, loss of privacy, noise and reduction of daylight.
- Local Plan Policy BNE1 (Design Criteria for New Development), which carries similar design and amenity tests into the determination of individual applications.
- Local Plan Policy HS5 (House Extensions), which deals specifically with the impact of extensions on neighbouring living conditions, including overbearing impact and loss of light.
These sit alongside the National Planning Policy Framework (NPPF), which expects a good standard of amenity for existing and future occupiers.
It is worth noting that the three Central Lancashire councils have prepared a new joint Central Lancashire Local Plan 2023-2041, which was submitted for independent examination on 30 June 2025 and was the subject of public hearings into early 2026. Until that plan is adopted, the 2012-2026 Local Plan and the 2012 Core Strategy remain the documents against which applications are decided, although the emerging plan may begin to attract weight as it progresses.
Is there a daylight and sunlight SPD in Chorley?
Chorley does not have a Supplementary Planning Document devoted solely to daylight and sunlight, but it does provide unusually clear design guidance for householders. The Council adopted a Householder Design Guidance SPD in January 2017, which supports Policies 17, BNE1 and HS5 and is used directly when assessing extensions. Among other things it applies the 45-degree guideline for assessing loss of light and over-dominance, and advises that a single-storey rear extension should generally not project more than 3 metres beyond that guideline. It also sets out how spacing guidelines are increased where slab levels differ between neighbouring properties. The borough is also covered by the Central Lancashire Design Guide SPD (2012), a joint document with Preston and South Ribble.
Where a numerical daylight or sunlight assessment is required, officers rely on the recognised national technical guidance rather than a bespoke local metric:
- BRE BR 209 (2022) – Site Layout Planning for Daylight and Sunlight: A Guide to Good Practice, the basis for the Vertical Sky Component (VSC), daylight distribution (no-sky line), Annual Probable Sunlight Hours (APSH) and overshadowing tests.
- BS EN 17037 – the British and European daylight standard, used for assessing the daylight provision of new dwellings.
- The NPPF and Planning Practice Guidance, applied through Policy 17, BNE1 and HS5.
What this means for development in Chorley
Chorley's geography shapes how daylight issues arise:
- Chorley town centre and its surrounding Victorian and inter-war terraces have tight back-to-back relationships, so rear extensions and loft conversions are routinely tested against the 45-degree guideline and BRE VSC values to protect neighbouring habitable room windows.
- The eastern part of the borough rises towards the West Pennine Moors, where sloping sites and significant differences in ground and slab levels make overshadowing and the Council's slab-level spacing adjustments particularly relevant.
- Edge-of-settlement and rural villages around Chorley combine larger plots with sensitive landscape settings, where sunlight to gardens and amenity space is a common consideration.
Submitting a clear daylight and sunlight report prepared to BRE BR 209 (2022) demonstrates compliance with Policy 17, BNE1 and HS5, helps the case officer, and reduces the risk of neighbour objections about loss of light.
How Fortress Associates can help
Fortress Associates provides our daylight and sunlight report service for homeowners, architects and developers across Chorley and the rest of the UK. Our reports follow BRE BR 209 (2022) and BS EN 17037 and are written to support your application under the relevant Local Plan and Core Strategy policies. We usually deliver within a 4 to 5 working day turnaround, with no advance payment required. We can also prepare Building Regulations drawings for your project. Browse our full list of services or contact us for a quote.
Sources & further reading
Need help with a UK planning project?
Fixed-fee daylight reports and Building Regulations drawings — delivered in 4–5 working days. No advance payment.
Request a free quote