You can try, but in Maida Vale nearly any change you can see from outside needs permission first, and most buyers will not own a house to extend. There are more than a thousand listed buildings in and around the district. More than a dozen conservation areas overlap it. Almost every home is a flat, and changing a flat needs the freeholder's consent on top of the council's. Your neighbours are still sending in planning applications by the hundred.
Historic England lists 1,065 buildings in and around Maida Vale: 17 at Grade I, 50 at Grade II* and 998 at Grade II. Listing protects the whole building, inside and out, so replacing windows, moving an internal wall or changing a staircase in a listed home needs listed building consent from Westminster City Council. Carrying out that work without consent is a criminal offence. A Grade II listing is the most common, and it is not a light one.
Thirteen conservation areas fall within the same stretch of west London, among them Maida Vale's own, Paddington Green and Bayswater. In a conservation area, the council can control demolition, roof alterations, front elevations and other external changes that are allowed automatically in many other places. Many owners in Maida Vale have a listed building, a conservation area and a freeholder to get past, all for the same change.
There is one scheduled monument in the same area. That is the highest level of protection, but unless your plot borders it, it is unlikely to affect your plans.
Westminster received 1,217 planning applications for Maida Vale between April 2024 and June 2026, 542 of them in the last twelve months. Owners here are clearly applying to change their homes. With so many applications, the conservation officers have a lot to get through, and yours will be one of them.
The British Geological Survey puts all of Maida Vale at class 3 for shrink-swell, which means clay ground that swells when wet and shrinks when dry. Every postcode in the district is in that class. For an extension, that usually means deeper foundations than on firmer ground and a structural engineer's report before a builder gives you a price. It is a known cost, and the Victorian and Edwardian mansion blocks have stood on the same ground for more than a century.
Six listed buildings in the area are on Historic England's Heritage at Risk register. That means they are in poor condition, may qualify for grant support for repairs, and get extra scrutiny from the council and Historic England. They are no danger to the owner of an ordinary flat nearby. Owning one of them means a restoration project with conservation experts watching.
In practice, permitted development rights, which let houses add some extensions without a planning application, do not apply to flats, and conservation areas restrict them even for houses. Listed buildings need consent whatever the size of the work. So with almost every home here a flat, and so much of the district listed or in a conservation area, most changes go through Westminster City Council. Ask the council whether the building is listed and which conservation area it is in, and read the lease's alterations clause, because the freeholder's consent is a separate hurdle that the council's decision does not cover.
The freedom to extend or alter a home is very limited in Maida Vale, and it is the district's main drawback for buyers. Buy a flat you are happy with as it is, because changing it will take a long time and may not be allowed.