Fixed fee from £1,575. MCIAT chartered. Kensington and Chelsea planning experienced. 2 postcodes covered: SW1X, SW7.
Knightsbridge is Regency and Victorian terraces, luxury. The dominant stock — regency and victorian terraces, mansion blocks — has specific constraints and opportunities for mansard roof extensions. Side returns sit better on bay-fronted Victorian terraces than on detached 1930s semis. Mansards work where the existing roofscape supports them. We design to the block, not the brochure.
Local context summary — Architectural Drawings London, MCIAT charteredMost mansard roof extensions projects in Knightsbridge fall under Permitted Development if the property is a house (not a flat), not listed, and not in a conservation area. Kensington and Chelsea has an Article 4 Direction — Article 4 Directions covering HMOs, office-to-residential, and basement developments — RBKC has some of the strictest basement policies in London. We confirm eligibility free at the site survey.
Drawings: fixed fee from £1,575 (Mansard Roof Extensions). Construction cost is separate and depends on size, finish and structural complexity. For regency and victorian terraces, mansion blocks (typical of Knightsbridge), expect £45,000–£85,000 build cost for a standard rear extension or loft, more for mansards or basements.
12–14 weeks from first call to RBKC Planning planning decision. Site survey week 1, design weeks 2–3, validation 1–2 weeks, statutory 8-week determination.
Knightsbridge is characterised by regency and victorian terraces, mansion blocks. We've delivered mansard roof extensions for every period represented here — the design choices vary significantly by stock.
Our first-time approval rate in Kensington and Chelsea is 98%. Pre-application advice from RBKC Planning is built into our process when the case is borderline (conservation area, Article 4, listed).
Same-day fixed quote. MCIAT chartered.
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