# 2 Island Cottages, Stanwell Road, Horton

- **Decision:** dismissed, 4 September 2026
- **Decided by:** Planning Inspector: S Ramsden
- **Authority:** Windsor and Maidenhead (South East)
- **Appeal reference:** 6009260
- **Application reference:** 25/03424/FULL
- **Procedure:** householder
- **Development:** Front gable, front/side and rear/side extensions, raised ridge, six dormers with Juliet balconies to a 1960s semi-detached bungalow
- **Site context:** green-belt, flood-zone-3
- **Green Belt:** yes (grey belt not-argued)
- **Framework applied:** August 2026 NPPF
- **Determinative policies:** GB7(1)(b), GB6(2), DP3, F4
- **Development plan policies:** RBWM Borough Local Plan 2022 QP3, QP5, NR1, Horton and Wraysbury NP 2020 NP/HOU1, NP/HOU2, NP/SUSTDEV 02
- **Main issues:** inappropriate development, openness, design, flood risk, VSC
- **Tags:** disproportionate-extension, householder, vsc-not-shown, openness-harm, flood-risk, design-refusal, transitional-no-consultation

## Summary
Remodelling of a heavily extended 1960s bungalow into a chalet-style house with a new roof storey and six dormers. Dismissed. At roughly 170-270% of the original it was disproportionate under GB7(1)(b), with limited openness harm, poor design and an inadequate FRA. No VSC.

## Issues and findings
- **Transition.** The changes "do not affect the merits of this case in a material way", so the parties were not consulted (DL ¶2).
- **GB7(1)(b): FAIL.** "around 170% of the original 1960s bungalow … around 270% if a first floor is included … Both figures indicate a disproportionate addition" (DL ¶9).
- **Openness:** "localised and limited … Whilst harm to the Green Belt would be limited in nature … it nevertheless attracts substantial weight" (DL ¶13).
- **Design and flood risk:** conflict (DL ¶17-18, 24).

## Planning balance
GB6(2) is "a high hurdle"; the limited considerations do not clearly outweigh (DL ¶27, 30).

## What made the difference
Cumulative enlargement well beyond the original building, compounded by poor design.

## Transferable points
- Limited, localised openness harm still attracts substantial weight under GB6(2) (DL ¶13, 27).

## Policy findings
- **GB7(1)(b): fail.** ~170% of the original floor area, ~270% with a first floor; significant volume increase (DL 8-10)
- **GB6(2): harm (substantial weight).** limited, localised spatial and visual openness harm on an enclosed island site (DL 13)
- **DP3: conflict.** unconvincing roof form, poorly aligned dormers; poor design (DL 14-19)
- **F4: conflict.** incomplete FRA (Flood Zone 2 or 3), no 1-in-100 plus climate change assessment (DL 20-25)

## Key facts
- Heavily extended 1960s semi-detached bungalow on a small island between branches of the Colne Brook, Metropolitan Green Belt
- New near-flat-roofed upper storey with six dormers on a similar footprint

## Sources
- https://appeal-planning-decision.service.gov.uk/comment-planning-appeal/appeals/6009260
- https://appeal-planning-decision.service.gov.uk/published-document/b2d30836-6bad-4002-800f-793fe554b06e

---

Source: https://planningdistilled.org/research/england/nppf-navigator/decisions/PINS-6009260.html

A summary of a public planning decision, written from the decision letter. Not legal advice. © Planning Distilled. Released under the Creative Commons Attribution 4.0 licence (https://creativecommons.org/licenses/by/4.0/): share and adapt freely, with credit to Planning Distilled. Quotations from decision letters, plans and the Framework remain the copyright of their publishers.