Anyone planning an extension, infill home or larger residential scheme across Northampton, Daventry or the former South Northamptonshire area needs to understand the daylight requirements in West Northamptonshire. Because this is a relatively new unitary authority built from several former councils, its planning framework is layered - and knowing which plan applies to your site matters. This guide explains that framework, the daylight and sunlight guidance the Council relies on, and how a BRE-compliant report supports an application.
Daylight requirements in West Northamptonshire: a layered plan
West Northamptonshire Council was created on 1 April 2021, replacing the former Northampton Borough, Daventry District and South Northamptonshire District councils (and the county council). It is the Local Planning Authority for the whole area. Crucially, there is not yet a single adopted local plan for the unitary; instead the development plan is made up of several documents:
- West Northamptonshire Joint Core Strategy (Part 1) - the strategic plan, adopted on 14 December 2014, covering the period to 2029. It sets the overarching design and sustainability principles for the whole area.
- Northampton Local Plan (Part 2) 2011-2029 - adopted March 2023, providing detailed development management policies for the Northampton area.
- Settlements and Countryside Local Plan (Part 2) for Daventry District 2011-2029 - adopted 20 February 2020.
- South Northamptonshire Local Plan (Part 2) - the detailed plan for the former South Northamptonshire area.
A single new West Northamptonshire Local Plan is being prepared to replace these documents; its Regulation 18 draft was consulted on between January and March 2026. Until it is adopted, the documents above carry full weight - so the correct policies for a given site depend on which former district it sits in.
The amenity and design policies that apply
For the Northampton area, the Northampton Local Plan (Part 2) is the most directly relevant document. Two policies are central to daylight and sunlight matters:
- Policy Q1 (Placemaking and Design) - requires high-quality, well-designed development that responds to its context.
- Policy Q2 (Amenity and Layout) - protects the living conditions of existing and future occupiers, addressing matters such as outlook, privacy and the avoidance of unacceptable harm to neighbouring amenity.
Across the wider area, the strategic Joint Core Strategy sets out sustainable development and design principles that all proposals must meet, and the Daventry and South Northamptonshire Part 2 plans contain their own amenity and design provisions for those areas. In every case, the test is the same in substance: development should not cause unacceptable harm to the daylight, sunlight, outlook or privacy of neighbours, and should provide good living conditions for new homes.
Is there a daylight and sunlight SPD?
West Northamptonshire does not currently operate a single, area-wide Supplementary Planning Document prescribing numeric daylight and sunlight standards. Where a quantitative assessment is required, the Council - in line with practice nationally - relies on the Building Research Establishment guide BRE BR 209 "Site layout planning for daylight and sunlight" (2022 third edition) and BS EN 17037, applied through the amenity and design policies above and the National Planning Policy Framework (NPPF). The NPPF encourages efficient use of land while protecting good living conditions, and BR 209 itself advises that its numerical guidelines should be applied flexibly.
What a BRE assessment covers
- Vertical Sky Component (VSC) - daylight to neighbouring windows, against the 27% target and the 0.8-times-former-value test.
- Daylight Distribution (No Sky Line) - the spread of daylight within affected rooms.
- Annual Probable Sunlight Hours (APSH) - sunlight to windows, winter and annual.
- Overshadowing of gardens and amenity space on 21 March.
Why the layered plan matters locally
Two practical points stand out. First, the same proposal could be judged against different detailed Part 2 policies depending on whether it lies in the Northampton, Daventry or South Northamptonshire area - so it is worth confirming the correct plan before designing a scheme. Second, much of West Northamptonshire's growth combines large urban extensions around Northampton with sensitive infill in historic stone-built villages across the former Daventry and South Northants districts; in both contexts a clear, evidence-based daylight and sunlight report helps demonstrate that a scheme respects neighbouring living conditions while making good use of land, exactly the balance the JCS and NPPF require.
How Fortress Associates can help
Fortress Associates provides our daylight and sunlight report service, assessing schemes to BRE BR 209 (2022) and BS EN 17037 and presenting clear results for planning officers, applicants and neighbours. We work nationwide with a 4-5 working day turnaround and no advance payment required. We also prepare Building Regulations drawings to Approved Documents A-S. To discuss a project in Northampton, Daventry or South Northamptonshire, please contact us.
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