- Decision
- dismissed, 16 September 2026
- Decided by
- Planning Inspector: Alice James
- Authority
- Horsham (South East)
- Appeal reference
- 6009032
- Application reference
- DC/25/2126
- Procedure
- written representations
- Development
- Detached single-storey granny annexe (flat roof, Passivhaus, PV) and detached workshop/gym in rear garden
- Site context
- inside settlement
- Green Belt
- No
- Framework applied
- August 2026 NPPF
- Determinative policies
- DP3(1), DP3(3), DP4, S4
- Development plan policies
- Horsham District Planning Framework 2015 Policies 32, 33, Billingshurst NP Bill 2
- Main issues
- character and appearance
Summary
A flat-roofed Passivhaus annexe and a pitched-roof workshop/gym in the rear garden of a detached house in a spacious close. Dismissed. The annexe would fill the visual gap between houses and clash with the prevailing roof forms, conflicting with DP3. It also failed DP4 because the appellant had not engaged with the Council on design. CC2(2) substantial weight was given for energy efficiency, but the benefits were substantially outweighed under S4.
What made the difference
The annexe's siting, visible through the gap between houses, and its flat roof. The inspector also treated failure to engage in the design process (no pre-application advice, amendments declined) as a DP4 conflict in its own right, which is an unusual use of DP4.
Policy findings
Policy codes are those of the National Planning Policy Framework (August 2026) unless a development plan is named.
| Policy | Finding | Weight | Note |
|---|---|---|---|
| DP3(1) | fail | substantial | annexe fills gap between houses, flat roof out of keeping; substantial weight to development-plan design compliance; DP3 "among the policies … which state that development should be refused" (DL 8-14, 23) |
| DP4 | fail | no pre-application engagement and Council's offer of amendments declined (DL 15) | |
| CC2(2) | benefit | substantial | Passivhaus and PV given substantial weight but outweighed (DL 23) |
Key facts
- Non-determination appeal; main issue identified from Council statement (DL 4)
- PD fallback limited weight because annexe use is outside PD and PD building would be lower (DL 11)
- S5 cited by appellant held inapplicable within settlement boundary (DL 25)
- Parties invited to comment on 17 Aug 2026 Framework (DL 2)
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.