- Decision
- dismissed, 11 September 2026
- Decided by
- Planning Inspector: Paul Martinson
- Authority
- Leeds (Yorkshire and the Humber)
- Appeal reference
- 6007478
- Application reference
- 25/06104/LI
- Procedure
- written representations
- Development
- Replacement of Yorkshire sliding sashes with double-glazed timber casements in Grade II listed house (LBC 6007478, planning 6007479)
- Site context
- conservation area, listed building setting, inside settlement
- Green Belt
- No
- Framework applied
- August 2026 NPPF
- Determinative policies
- HE6(3), HE6(4)
- Development plan policies
- Leeds Core Strategy 2014 P10, P11, Leeds UDP Review 2006 saved N14, N17, N20
- Main issues
- listed building; conservation area
Summary
A Grade II house in the Colton Conservation Area sought to replace its Yorkshire sliding sashes with double-glazed timber casements. Both appeals were dismissed. The letter states that it applies the 2026 Framework, but then describes the HE6(1) weight as "great weight" and grades harm as "a moderate to high level of 'less than substantial' harm as set out in the Framework". Neither phrase appears in the 2026 text. The HE6(4) energy-efficiency example was engaged but discounted because less harmful alternatives were not excluded.
Issues and findings
- Significance of non-original windows. The windows were "not historic" but "have a degree of authenticity … contribute in a positive way to the listed building's architectural merit" (DL ¶12).
- Harm. Thicker frames and double-glazed units "would be easily identifiable as modern windows" (DL ¶18).
- Misstated Framework. "the Framework sets out that great weight should be given … irrespective of whether any potential harm amounts to substantial harm, total loss or less than substantial harm … a moderate to high level of 'less than substantial' harm as set out in the Framework" (DL ¶23). This is 2024 ¶212 wording presented as the new Framework.
- Energy: HE6(4). "Important public benefits can include enabling energy efficiency measures" (DL ¶24). But "it has not been demonstrated that the window style proposed would be the only means of achieving those benefits" (DL ¶25). "secondary glazing or … slimmer double glazed units" were not ruled out (DL ¶26).
Planning balance
HE6(4). Limited public benefits against considerable importance and weight to the harm (DL ¶28).
What made the difference
The loss of a locally distinctive window type with no heritage analysis to justify it, and no evidence that secondary glazing or slim double glazing had been considered.
Transferable points
- HE6(4)'s energy-efficiency example does not unlock double glazing in listed buildings unless the appellant shows less harmful options (secondary glazing, slim units) will not do (DL ¶¶25–26).
- Even Inspectors who say they apply the 2026 Framework sometimes restate 2024 ¶212 as if it were current (DL ¶23). Worth watching for challenges.
Policy findings
Policy codes are those of the National Planning Policy Framework (August 2026) unless a development plan is named.
| Policy | Finding | Weight | Note |
|---|---|---|---|
| HE6(3) | harm | considerable | "a moderate to high level of 'less than substantial' harm as set out in the Framework" (sic): thicker frames, 24-28 mm units, loss of Yorkshire sliding sash type; also harms Colton CA (DL 15-23) |
| HE6(4) | fail | limited | HE6(4) energy-efficiency example acknowledged, but not shown that this design is the only way; secondary glazing or slim units not ruled out; security limited (DL 24-28) |
Key facts
- Existing windows not historic (post-1976) but authentic in type and valued as contributing to architectural merit
- No detailed existing drawings or heritage analysis submitted
Sources
This note is one of the decisions behind the NPPF 2026 Navigator, which shows how each Framework test has been applied across all the decisions in the database. Also available as Markdown.