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Mikael Armstrong v Secretary of State for Levelling-Up, Housing and Communities & Anor.

[2023] EWHC 176 (Admin)
Someone wanted to change the design of their house, but only needed to change the conditions on their planning permission, not the whole permission itself. The rules for changing planning permission conditions (section 73) allow big changes if they don't change the main type of building allowed. The inspector wrongly said the change was too big, so the court overturned his decision.

Key Facts

  • Mikael Armstrong challenged a planning inspector's decision dismissing his appeal against Cornwall Council's refusal of a section 73 application.
  • The application sought to vary a condition of an extant planning permission for a dwelling, altering its design from a modernist to an alpine lodge style.
  • The main issue was whether the Inspector lawfully concluded the application constituted a fundamental variation outside section 73's scope, despite not conflicting with the original permission's description of the development.
  • The original planning permission was for 'Construction of one dwelling' with conditions referencing specific drawings.
  • A section 96A amendment later added a condition specifying eight of the drawings for the dwelling's construction.
  • The section 73 application proposed substituting these drawings with new ones showing a significantly different dwelling design.

Legal Principles

Section 73 of the TCPA 1990 allows applications to vary conditions of a planning permission, but it does not define 'minor material amendment'.

Town and Country Planning Act 1990, section 73

Section 96A of the TCPA 1990 allows non-material changes to planning permission.

Town and Country Planning Act 1990, section 96A

A section 73 application cannot change the description of the development in the operative part of the planning permission (Finney principle).

Finney v Welsh Ministers [2019] EWCA Civ 1868

Planning Practice Guidance (PPG) provides non-binding commentary on sections 73 and 96A; it's not legally binding.

Planning Practice Guidance

The interpretation of a planning permission is a matter of law, focusing on what a reasonable reader would understand.

Hillside Parks Ltd v Snowdonia National Park Authority [2022] UKSC 30

Section 73 applications are limited to variations of conditions; they cannot fundamentally alter the description of the development itself.

R v Coventry City Council ex p Arrowcroft Group Plc [2001] PLCR 7; R(Vue Entertainment Ltd) v City of York Council [2017] EWHC 588 (Admin); Finney v Welsh Ministers [2019] EWCA Civ 1868

Outcomes

The Inspector's decision was quashed.

The Inspector erred in law by applying a test of 'fundamental variation' to a section 73 application that did not conflict with the operative part of the planning permission. He also misdirected himself by relying on the PPG's concept of 'minor material amendments,' which is not a statutory limitation on section 73.

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