Fixed fee from £1,575. MCIAT chartered. Lambeth planning experienced. 1 postcode covered: SE24.
Herne Hill is Victorian villas around Brockwell Park. The dominant stock — victorian villas, edwardian terraces — 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 Herne Hill fall under Permitted Development if the property is a house (not a flat), not listed, and not in a conservation area. Lambeth has an Article 4 Direction — Borough-wide Article 4 for HMO conversions; plus office-to-residential restrictions. 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 victorian villas, edwardian terraces (typical of Herne Hill), 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 Lambeth Council planning decision. Site survey week 1, design weeks 2–3, validation 1–2 weeks, statutory 8-week determination.
Herne Hill is characterised by victorian villas, edwardian terraces. We've delivered mansard roof extensions for every period represented here — the design choices vary significantly by stock.
Our first-time approval rate in Lambeth is 98%. Pre-application advice from Lambeth Council is built into our process when the case is borderline (conservation area, Article 4, listed).