Flat conversion drawings in Westminster

How heritage controls shape a Westminster conversion

Heritage is the other filter. The council publishes 56 conservation areas and 10 Article 4 directions, and Historic England lists 4,015 entries within the borough, of which 205 are Grade I. A house in Belgravia, Marylebone or Bayswater may meet at least one of these.

That changes the drawings. New doors, bin stores, flue terminations and ventilation grilles all land on the front elevation, and a conservation officer will read each one. We draw them early, on the elevations, so the entrance for the upper flat is resolved before the layouts are fixed. Where the building is listed, the conversion needs separate consent, which is outside this page; see architectural drawings in Westminster for the wider picture of constraints.

What the planning record says about flat schemes here

Schemes of fewer than ten homes are counted as minor development in the government's statistics. In the latest twelve months Westminster decided 1,766 minor applications, granted 85.8 per cent of them and decided 83.6 per cent within eight weeks or an agreed extension. That is a busy, relatively predictable desk, which is useful when you are choosing between layouts.

Money matters too. The Mayor's levy for Westminster falls in charging band 1, and for permissions granted this year the indexed rate is £96.97 per square metre. The usual exemption for small additions does not apply when a new dwelling is created, so we flag liability in our hand-over notes. The council fee for the change of use is £610 for each dwelling formed.

Sizes and heights Westminster officers will measure

Every flat is tested against the nationally described space standard, and London's own rule asks for a floor-to-ceiling height of 2.5 m across three quarters of each flat. Lower-ground floors in Westminster's stucco terraces often miss that figure, so we measure before promising a layout on that level.

Outdoor space is the other recurring check. Central terraces rarely have gardens to share, so balconies, roof terraces and lightwells are tested against the London Plan rule for private space. Our planning drawings set carries the area schedule that shows each result.

What we draw for a Westminster conversion

You get existing and proposed plans for every floor, elevations and sections, a block plan and the area schedule, all taken from one Revit model of a measured survey. A second chartered technologist checks every sheet, never the person who drew it, and we submit through the Planning Portal.

After consent the same model feeds building regulations drawings for the sound, fire and drainage details. Prices are published, fixed and include VAT, and if the council asks for changes we redraw at no charge until approval.

Choosing which Westminster houses are worth converting

Not every Westminster address suits subdivision. Only 10.2 per cent of the borough's 94,815 households live in a house or bungalow, and just 27.4 per cent own their home, so a whole house in single ownership is the exception. A terraced house averages about £1,616,250, against £775,956 for a flat, which means the value is carried by the building, and every square metre lost to a stair or a lightwell is expensive.

We therefore advise on a short list of checks before you buy or commit. Is the house in one title, with no leases? Does the lower ground floor reach a usable height? Can the upper flat have its own door without cutting into the principal rooms? Is the street full of existing conversions, which would make a family-sized unit harder to justify against the protection policy? If the answers are good, a conversion can be worth far more than the house as it stands.

Many central houses are already split. If yours is, the question changes from conversion to reconfiguration, which the City Plan treats more cautiously because it protects existing floorspace. For leasehold situations, see our lease plans page, and to confirm what is already lawful, lawful development certificate drawings in Westminster is the route.