Class Q refusal rate
Costs verified against BCIS Online (May 2026 release) and ONS Construction Output Price Index, April 2026. Class Q rules current to the 21 May 2025 GPDO amendment.
Class Q refusal has historically run at around 50% to 60% nationally, on the gov.uk live tables for planning application statistics. The 2025 widening will reset that baseline over the next two years.
What the published statistics show
The DLUHC / MHCLG live tables on planning application statistics separate prior-approval cases. Pre-2024, the Class Q approval rate hovered between 40% and 50% nationally, with material LPA variance. Refusal clusters around three repeat grounds.
The three repeat refusal grounds
- Structural viability. The building cannot convert without effectively rebuilding it, falling outside Class Q.
- Highway access. Sub-standard track, poor visibility splay, no passing places on a private lane.
- Location, design and external appearance. Particularly visible barns in sensitive landscapes, or proposals that propose substantial new openings.
How to de-risk before submission
- Commission a chartered structural engineer's appraisal early and submit it with the application.
- Pre-app with the LPA where the duty planner will engage (some refuse to pre-app Class Q on principle).
- Hold the existing openings and avoid asking for new fenestration that materially changes the elevation.
- Use a specialist Class Q consultant with a documented win rate, not a generalist planner.
Sources cited on this page