Householder appeal win — refused mansard loft in CA approved on appeal

Brief

Family of 4 in 1885 Kilburn NW6 Victorian terrace needed master suite + 2nd bathroom. Existing loft uneconomical for hip-to-gable due to slope orientation; only viable scheme was full mansard rear + dormer combination = 42m² net new floor area. Brent Council refused application September 2024 on 2 character grounds: (1) 'dominance + visual prominence in the conservation area' contrary to UDP policy CP4; (2) 'inadequate justification for departure from Brent Mansard Roof SPD parapet detailing'. Officer report had recommended approval; committee overturned 6-4 on member concerns raised at site visit. Builderr engaged immediately post-refusal to pursue HAS appeal — strong comparator evidence + officer recommendation supported high-confidence appeal viability.

Challenge

Brent Planning Committee refused September 2024 against officer recommendation to approve — 6-4 vote — citing committee member concerns about 'dominance' raised informally at pre-decision site visit. Refusal reasons drafted post-vote, comprised: (R1) the proposed mansard by reason of its scale, prominence + materials would result in unacceptable dominance + visual harm to the Kilburn Conservation Area contrary to UDP policy CP4 + NPPF section 16; (R2) the proposal fails to demonstrate compliance with Brent Mansard Roof SPD 2018 paragraph 4.3 parapet detailing requirements. Critical strategic factors: (1) officer report had recommended approval after 12-week determination + 4 rounds of pre-application engagement — officer found scheme acceptable; (2) committee overturned without commissioning supplementary heritage assessment + reasons drafted retrospectively to support vote; (3) Brent had approved 11 mansards within 500m radius of site in 2020–2024 period — 8 with identical or smaller setback + dormer treatment; (4) Brent's own Mansard Roof SPD 2018 included design diagrams matching the refused scheme's parapet detail almost exactly. High-confidence appeal viability — Builderr commissioned independent planning consultant review before committing: 65–75% odds of allowance on written representations procedure. Strategy: aggressive comparator-led SoC + Brent SPD precedent argument + costs application on member overturn without basis. Twin-track revised application not pursued — Builderr judgement was committee would likely refuse revised scheme again to defend original vote.

Solution

Filed Householder Appeal Service (HAS) appeal 16 days after refusal — within 84-day window. Written representations only (mandatory under HAS). Statement of Case 21 pages + 9 appendices (108-page bundle): (1) site + scheme description with full design rationale; (2) planning history — pre-app engagement chronology + officer recommendation evidence; (3) Reason 1 rebuttal — 8 comparator schemes within 200m mapped + photographed with LPA reference numbers (Brondesbury Villas × 3, Mazenod Avenue × 2, Christchurch Avenue × 2, Brondesbury Park × 1), all approved 2020–2024, all with identical or larger mansard footprint, all in Kilburn CA, demonstrating that 'dominance + visual harm' character finding was inconsistent with Brent's own approval pattern; design analysis section showed refused scheme had smaller relative dormer width than 5 of 8 comparators + matching slate spec; (4) Reason 2 rebuttal — paragraph-by-paragraph analysis of Brent Mansard Roof SPD 2018 with diagram cross-references showing refused scheme parapet detail exactly matched SPD Figure 4.7 'recommended detailing' — argued LPA had misread own SPD; (5) appeal precedent — 3 PINS decisions cited (APP/T5150/W/23/3319847 + 2 others) where committee overturning officer recommendation without supplementary evidence was reversed; (6) costs application under PPG Costs paragraph 049 — committee overturned officer report without commissioning supplementary heritage assessment + drafted reasons retrospectively to support member concerns raised at informal site visit; (7) Conclusion + relief sought. Appendices: 8 comparator approval notices + photographs + LPA reference numbers; Brent Mansard SPD 2018 extract; officer report (Pages 1-18); committee minutes; 3 PINS precedent decisions; design statement amendments (none — scheme as refused); heritage consultant statement (Heritage Collective Ltd, £2,400 commissioned for appeal — character + setting assessment confirming no harm); daylight/sunlight BRE 209 assessment confirming no impact on neighbours; Brent Council UDP policy CP4 full text with annotations. Construction scope: subject to appeal allowance, 14-week mansard + dormer build (£142k including kitchen-loft staircase + landings refit + new bathroom + master suite + structural steels + party wall × 2).

Outcome

PINS Inspector site visit week 11 (accompanied — Inspector requested view from adjacent rear gardens by neighbour agreement). Decision issued week 19 from lodging (HAS target 12 weeks; backlog adding 7 weeks) — appeal ALLOWED, both refusal reasons OVERTURNED. Inspector findings on Reason 1: '...The 8 comparator schemes presented within 200m radius are persuasive. Each is in the same conservation area, each is of equivalent or greater mansard scale + each was approved by the same LPA in the past 4 years. The appellant's analysis of relative dormer proportions is correct. I find no basis for the conclusion that this scheme would result in unacceptable dominance when the LPA has consistently approved equivalent or larger schemes nearby. The character of the conservation area accommodates the proposal as it accommodates the comparators...' Inspector findings on Reason 2: '...I have reviewed the Brent Mansard Roof SPD 2018 paragraph 4.3 + Figure 4.7 with care. The proposed parapet detail matches the SPD's recommended detailing precisely. The LPA's contrary finding is not supported by reference to specific divergence from the SPD requirements. Reason 2 is not made out...' Costs application Inspector awarded PARTIAL costs £8,500 — finding committee had overturned a reasoned officer recommendation without commissioning supplementary heritage assessment + the refusal reasons had been drafted to support member concerns raised at informal site visit without proper evidential basis (PPG Costs paragraph 049). Brent issued planning permission within 14 days of appeal decision under Inspector's grant. Builderr construction 14-week mansard + dormer build commenced 6 weeks after permission: scaffold + roof strip week 1; structural steels + ridge beam week 2–3; mansard timber framing + slate underlay week 3–5; natural Welsh slate cladding to mansard + dormer week 5–6; lead flashings + parapet detail (the contested detail) week 6–7; sash window installation week 7; insulation + plasterboard week 7–9; second-fix + bathroom + master suite finish week 9–12; landing + new staircase week 11–12; snagging + final building control week 13–14. Brent CA Officer reviewed completed mansard at building control completion — formally confirmed compliance with permitted scheme + commented favourably on parapet execution. Property valuation: pre-loft 4-bed + 1-bath valued £1.085M; post-loft completion 5-bed + 2-bath valued £1.395M (+£310,000 on £142,000 build = 218% gross ROI). Costs award + appeal consultant fees + heritage consultant: £8,500 award covered Builderr's £6,800 appeal fees + £2,400 heritage consultant + left £700 balance to client. Builderr first formal HAS appeal win with costs award + first appeal-led mansard delivery; Brent 2nd borough portfolio case study (after Queens Park 2026 sprint 82/86); Kilburn NW6 first Builderr project. Decision cited in subsequent Brent appeal Brondesbury Park 2026 — establishing pattern of LPA committee mansard overturns being reversed by PINS. Featured in Planning Magazine June 2026 + Brent Civic Society case study + Royal Town Planning Institute London branch CPD case bulletin.