Double-storey extension drawings in the City of London

Heritage drives the design here

Historic England lists 637 entries inside the boundary, and 86 of them are Grade I. The borough also contains 53 scheduled monuments. A second storey that is hidden behind a modest rear wall in another borough can be a different proposition when it sits beside a listed neighbour or over buried remains.

We start by mapping those constraints on your plot. If the house is listed, an extension needs listed building consent as well as planning permission, and the drawings carry more detail on junctions, materials and what is being removed. The council has 1 Article 4 direction on record, which we also check for your address.

What the council's own record tells you

The Corporation decided only 1 householder application in its latest published year, and granted 100 per cent of them, in time. One decision is no pattern, and it tells you nothing about your own scheme. Treat it as a sign of how few householder cases the planning team sees, not as a forecast.

Domestic gardens make up 0.1 per cent of land in the borough, from the Greater London Authority's land-use survey. There is little rear garden to build into, so we look first at the footprint you already have, such as adding a floor over an existing single-storey part.

Upper-floor windows, escape and structure

Even in a dense setting, the technical rules apply as they do anywhere. Upstairs side windows need: Upper-floor side windows obscure-glazed and non-opening below 1.7 m above floor. A new bedroom over a ground-floor room needs an escape window; the Approved Document describes it as: 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.

Where your house shares a wall with a neighbour, the Party Wall Act applies. Cutting into one needs: Party structure notice at least 2 months before work. We prepare the drawings the surveyor needs for that notice, and our party wall notices service handles the paperwork if you want it.

Cost, route and what you receive

Our fee is £1,295 with VAT included, quoted before you commit. The council's own fee for a householder application is £548, paid to the council.

You receive existing and proposed plans for both floors, elevations, sections, and the location and block plans, with a second chartered technologist checking every sheet. If the council asks for changes, we redraw at no charge until approval. Where the route is planning permission, see how we prepare planning drawings for a householder submission.

Related drawings and nearby boroughs

For the borough as a whole, start at architectural drawings in City of London. Thinking about a smaller step first? Rear extension drawings in City of London cover a single-storey addition, and loft conversion drawings in City of London add space without touching the footprint. The national rules sit on the double-storey extension drawings hub. Next door, compare Hackney and Westminster.