Double-storey extension drawings in Lambeth

Reading the back of a Lambeth house

Before designing, we record the closet return, the back addition and the eaves on a measured survey, with the neighbour's rear elevation. A half-storey stop below the eaves is a small dimension, and it only reads correctly against a drawing that shows the true eaves line.

The survey also picks up the stair, because a taller closet return often affects the top landing, and the bathroom above a new kitchen needs a drainage route. Those details land in the drawings, which saves a rework once the structural engineer is involved.

Conservation areas and Article 4 directions

Lambeth has 64 conservation areas, and the 12 Article 4 directions cover 223 areas. Historic England lists 953 entries. We check the address against all three before drawing.

Inside a conservation area: No rear extension of more than one storey under PD on article 2(3) land. See architectural drawings in Lambeth for the borough-wide checks.

When a second storey is permitted development

The national rule is: Over one storey: max 3 m beyond the original rear wall and not within 7 m of the rear boundary. Where a plot misses it, the upper floor goes to the council as a householder application.

Where a scheme qualifies, two conditions apply. Upper side windows: Upper-floor side windows obscure-glazed and non-opening below 1.7 m above floor. Roof: Roof pitch of a 2+ storey enlargement to match the original house so far as practicable.

Escape windows and party structure notices

A first-floor bedroom needs an escape window: 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. For shared walls: Party structure notice at least 2 months before work. We show both on the drawings, which also feed the later building regulations drawings in Lambeth.

How Lambeth has decided householder cases

Lambeth decided 595 householder applications in its latest published year, granted 83.4 per cent and decided 93.4 per cent on time. These cover every type of householder scheme, so they inform timing, not the likely result for one house.

Roofs, stairs and drainage on a Lambeth upper floor

The roof decides how a Lambeth upper-floor scheme reads. We draw the new roof in section against the old one, mark where the two meet and show the eaves line from the street side where it is visible. A gap that is only half a storey is a small thing to get wrong on site, so the dimension is written on the sheet.

The stair and the drains follow. A taller closet return often means moving the top of the stair or adding a soil pipe where the old house had none, and both need a route through the structure. We settle them on the drawings so the engineer is working from a layout that already allows for them.

The council's guide also warns against harm to amenity, which in practice means the daylight to the neighbour's back rooms and the outlook from their garden. The model lets us show the shadow cast at the worst time of day, and where it is too heavy we lower the new floor or shorten the return before the application, not after a letter.

Your drawings, price and neighbouring services

A Lambeth set includes both floors, the roof section, elevations and site plans. It starts at £1,295 with VAT included, fixed up front, and we redraw free until approval if the council asks for amendments.

If a closet return is not the right base, see loft conversion drawings in Lambeth or rear extension drawings in Lambeth. The same service nearby is at Southwark and Wandsworth.