Irwin Mitchell’s Planning & Environment Blog

Each month, we will be bringing together the latest articles written by our team covering key developments, legal insights, and practical guidance across the planning and environmental law landscape. Whether it's new legislation, landmark cases, or upcoming policy changes, our aim is to keep you informed about what is happening in the planning and environmental world.

In this edition, we are highlighting the articles we have published during April. We hope you find them insightful and useful in your work.

Explore the highlights below:

EAC publishes PFAS report - a steer in the right direction for the UK Government?

By Chyna Fairclough-Jones

Published 1 May 2026

The Environmental Audit Committee’s Addressing the Risk from PFAS report broadly welcomes the Government’s PFAS Action Plan but criticises its slow pace and lack of clear direction. The Committee calls for accelerated reform of UK REACH, closer alignment with the EU, and a shift away from substance‑by‑substance regulation towards a phased restriction on non‑essential PFAS uses from 2027, warning that delay undermines the precautionary principle and risks environmental, health and commercial harm.

The report also stresses that regulation will be ineffective without proper enforcement, urging meaningful application of the polluter pays principle, improved transparency, and better resourcing of regulators. It highlights knock‑on effects for the planning system, where uncertainty over PFAS contamination and remediation could hinder development. Overall, the EAC presents a clearer and more urgent roadmap for action, while acknowledging the scale and complexity of the reforms required.

What’s ahead for BNG: Government publishes responses to BNG consultations

By Elizabeth Mutter

Published 17 April 2026

The Government’s responses to two biodiversity net gain (BNG) consultations indicate a recalibration of the regime to improve proportionality and flexibility across development types. Mandatory BNG for nationally significant infrastructure projects (NSIPs) has been delayed again and will now apply only to applications submitted on or after 2 November 2026. Greater delivery flexibility is also proposed for NSIPs, with on‑site and off‑site biodiversity gains treated equally and statutory credits remaining a last resort.

For non‑NSIP development, new exemptions and reforms aim to reduce burdens on smaller sites. A new exemption for developments up to 0.2 hectares, where no priority habitats are affected, is expected to remove around half of residential permissions from BNG, though this may reduce short‑term biodiversity unit delivery. Conversely, the exemption for small self‑build and custom‑build schemes will be removed. Further reforms to minor development are planned for later in 2026, including equal treatment of off‑site gains.

The responses also propose technical and procedural changes, including exemptions for biodiversity‑led and temporary development, digitalisation of the biodiversity metric, and use of Local Nature Recovery Strategy areas for spatial risk. With many changes expected via secondary legislation before the summer recess, the BNG regime remains in active development.

Planning permission overturned for irrational reasoning and apparent bias

By Chyna Fairclough-Jones

Published 9 April 2026 

In R (Perrin) v North Devon District Council [2026] EWHC 535 (Admin), the Planning Court quashed a permission for a single open‑market dwelling, finding that the council had acted irrationally and was affected by apparent bias. The case highlights the risks where a planning committee departs from officer advice without providing clear, policy‑based reasons. The court held that the committee failed to adequately explain why it disagreed with the officer’s conclusion that the proposal conflicted with Local Plan policies favouring affordable housing, particularly in circumstances where the tilted balance applied due to a lack of five‑year housing land supply. 

The judgment also provides important guidance on decision‑making conduct, with the court upholding a finding of apparent bias arising from a councillor’s personal familiarity with the applicants and influential role in the committee’s deliberations. Even without the policy errors, this alone would have been sufficient to quash the permission. Overall, the decision reinforces the need for committees to engage directly with officer reasoning when reaching a contrary view and underlines the high standards of impartiality required of councillors involved in planning decisions.