Construction drawings in Westminster

A listed and protected borough

The council publishes 56 conservation areas and 10 Article 4 directions, and Historic England lists 4,015 entries. There are also 28 registered parks and gardens, 1 World Heritage Site and 23 heritage assets at risk.

Only 10.2 per cent of households live in a house, and 27.4 per cent are owner-occupiers. Most work is in flats within converted townhouses, where the lease, the listing and the neighbours all have a say. A Grade II* house needs a different approach to a modern block, and the first conversation is about what the fabric can bear.

Fire, stairs and old buildings

Old buildings do not suit modern dimensions easily. For stairs: Private stair: rise 150-220 mm, going 220-300 mm, max pitch 42°, 2R+G 550-700 mm. For headroom: 2.0 m clear headroom over stairs. For escape windows: Escape window: unobstructed openable area at least 0.33 m², at least 450 mm high and 450 mm wide, bottom of opening no more than 1100 mm above floor.

In a listed house the standards must be met without wrecking the character. We often propose the compliant solution at the rear, a secondary stair, or an alternative fire strategy, rather than altering a principal staircase. Building control can accept a different route when it can be shown to perform; we draw it clearly enough to make that conversation short.

Westminster's decision figures

In the latest published year the council decided 366 householder applications and granted 82 per cent. Only 79 per cent were decided in time. In the national tables the council reports 81.3 per cent granted of 418 householder decisions.

The two sources may differ in period and definition. We quote both rather than choosing the better one. Neither is a forecast, and a listed building consent runs on its own timetable.

Mews, townhouses and the practical limits

A Westminster set must often work around a site that is hard to reach. A mews house may be reached by a cobbled lane too narrow for a lorry, and a townhouse basement may sit under a protected pavement. We record access, hoisting and storage on the drawings because they decide what the work costs.

Services are the other pinch. Old houses have little space for new ducts, so we route the new work early and show the routes in section. A bathroom added to an upper floor, for example, needs a soil stack that does not run through a protected ceiling.

If a listing applies, we draw two things: the proposed work and the evidence that it leaves the fabric as it was where it matters. That is the material a conservation officer reads.

Scope, levy and related services

The fee is fixed after our free check. Westminster's levy varies by area: £811.80/m² (Prime); £590.40/m² (Core); £295.20/m² (Fringe) [schedule rates £550, £400, £200]. Check which zone your property sits in before you budget.

For regulations submissions see building regulations drawings in Westminster; for structure, structural calculations in Westminster. The borough summary is architectural drawings in Westminster. We also work next door in Camden, Brent and City of London.