Harley Street / Marylebone — covered by Westminster City Council. Fixed-fee planning, building regs, loft, extension and mansard drawings from £840.
From £840. Planning permission drawings delivered by an MCIAT chartered team.
From £840. Building regulations drawings delivered by an MCIAT chartered team.
From £1,225. Loft conversion drawings delivered by an MCIAT chartered team.
From £1,225. House extension drawings delivered by an MCIAT chartered team.
From £1,575. Mansard roof extensions delivered by an MCIAT chartered team.
From £995. Garage conversion drawings delivered by an MCIAT chartered team.
From £1,950. Basement conversion drawings delivered by an MCIAT chartered team.
From £350. Structural calculations delivered by an MCIAT chartered team.
From £450. Party wall services delivered by an MCIAT chartered team.
From £1,225. Rear dormer drawings delivered by an MCIAT chartered team.
W1G primarily covers Harley Street / Marylebone in Westminster.
Decisions for W1G are made by Westminster City Council. Standard Permitted Development rules apply for most rear extensions and loft conversions on terraced and semi-detached houses, unless the property is in a conservation area, is listed, or sits under an Article 4 Direction. Article 4 in Westminster: Yes.
Fixed fees: Planning drawings from £840 (Essentials) or £1,750 (Complete). Loft from £1,225. Mansard from £1,575. Building regs from £950. We do not charge hourly. Free site survey across all W1G addresses.
From first call to planning decision: typically 12–14 weeks. Site survey week 1, design weeks 2–3, validation 1–2 weeks, statutory 8-week determination. Westminster City Council timelines align with the national norm.
Harley Street / Marylebone in W1G is characterised by the housing stock of Westminster — broadly grand georgian and regency terraces in belgravia and pimlico.