- Decision
- dismissed, 15 September 2026
- Decided by
- Planning Inspector: N Praine
- Authority
- Tower Hamlets (London)
- Appeal reference
- 6008490
- Application reference
- PA/25/01373
- Procedure
- written representations
- Development
- Replacement of four timber sash windows with double-glazed timber units in first-floor flat of Grade II listed terrace (retrospective)
- Site context
- listed building setting, conservation area, inside settlement
- Green Belt
- No
- Framework applied
- August 2026 NPPF
- Determinative policies
- HE6(1), HE6(3), HE6(4), HE4(2)
- Development plan policies
- Tower Hamlets Local Plan 2020 S.DH1, S.DH3, London Plan 2021 HC1
- Main issues
- Grade II listed building; conservation area; public benefits
Summary
Retrospective double-glazed replacement sashes in one flat of a Grade II listed Hackney Road terrace. Both the planning and listed building consent appeals were dismissed. The harm was "at the lower end of the scale" but still "of considerable importance and weight". The energy-efficiency benefit got only limited weight: it was unevidenced, and less harmful alternatives had not been shown to have been discounted.
Issues and findings
- Significance. The windows "form a key component of that significance and are referred to in the list description" (DL ¶14).
- Harm: HE6. The wider, bulkier frames "would diminish the delicacy and refinement of the existing sash window design" (DL ¶13). "The proposal would result in harm, albeit at the lower end of the scale given the modest nature of the works. Nevertheless, this is of considerable importance and weight" (DL ¶16).
- Energy efficiency — CC2(2) vs HE6(4). The inspector accepted that "enabling energy efficiency would be an important public benefit and substantial weight should be given to the benefits of improving the energy efficiency of existing buildings". However, "evidence showing energy efficiency gains from the proposed works has not been submitted. Even if it had, I have not been provided with clear and convincing evidence that other, less harmful, energy-efficiency measures have been considered and discounted … I therefore ascribe it limited positive weight" (DL ¶17).
Planning balance
HE6(4): "The public benefits either alone or in combination would be insufficient to outweigh the substantial weight attached to the heritage harm identified" (DL ¶19).
What made the difference
Evidence. Neither the repair case nor the energy-efficiency case was documented. The new Framework's express support for energy efficiency (HE6(4), CC2(2)) was acknowledged but reduced to limited weight because the appellant had not quantified gains or tested less harmful alternatives, such as the slimline and vacuum glazing approved next door.
Transferable points
- HE6(4) and CC2(2) make energy efficiency an "important public benefit" that attracts substantial weight in principle. That weight is lost without evidence of the gains and of less harmful options having been considered (DL ¶17).
- Harm is still graded on a scale ("lower end of the scale"), not labelled "less than substantial" (DL ¶16).
- The letter elides the weights, speaking of "the substantial weight attached to the heritage harm" (DL ¶19) where HE6(3) speaks of harm as a matter of considerable importance and weight.
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(4) | harm | considerable | grading "harm, albeit at the lower end of the scale given the modest nature of the works. Nevertheless, this is of considerable importance and weight" (DL 16) — HE6(3) wording; HE6(1) substantial weight to conservation stated; HE4(2) clear and convincing justification stated; ss16/66/72 cited (DL 3); wider, bulkier stiles/rails, horns, deeper glazing (DL 12-15) |
| HE9 | harm | same harm to Hackney Road CA; Appraisal lists window loss as a threat (DL 15) | |
| CC2(2) | benefit | limited | code mapped by harvester — "enabling energy efficiency would be an important public benefit and substantial weight should be given to the benefits of improving the energy efficiency of existing buildings", but no evidence of gains or that less harmful options were discounted, so "limited positive weight" (DL 17) |
| E1 | benefit | limited | economic benefit limited given scale (DL 18); noise reduction and operation/safety gains also limited (DL 23-24) |
Key facts
- Appeal A 6008486 (planning, PA/25/01372) and Appeal B 6008490 (LBC) decided together; works complete (DL 2, 5)
- No evidence on condition of original windows, so repair not shown to have been explored (DL 11)
- Comparators at Nos 345 (vacuum glazing, 0.1mm gap) and 365 (slimline, white spacers) distinguished (DL 21-22)
- Parties consulted on 2026 Framework (DL 4)
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.