W9 · Maida Vale & Little Venice

Partly — and which part matters. A postcode district is never uniformly designated: W9 contains 9 conservation areas within 1km of its centre, and whether your own property sits inside one decides whether permitted development survives. The centre point of W9 itself does not fall inside one — but many of its streets will.

Yes — W9 has 11 Article 4 directions mapped within 1km of its centre. An Article 4 direction withdraws specific permitted-development rights on the streets it covers, which is the most common reason a project that looks like permitted development turns out to need a full application. The centre point of W9 falls inside Article 4 Basement Development Permitted Rights Removed.

Three routes exist, and which one you are on is decided by your address, not your postcode district:

W9 contains mapped conservation-area or Article 4 geometry, so a meaningful share of its streets will have lost some permitted-development rights — which pushes those properties onto the full-application route. Whether yours is one of them is an address-level question, not a district-level one.

A refusal is a decision notice with reasons attached, and those reasons are a roadmap. Most homeowners in Westminster — as anywhere in England — are better served by amending the scheme and using the free resubmission than by appealing: you get one further application on the same site within 12 months without paying again.