Double-storey extension drawings in Lewisham

Making a case for exceptional design

When a rear two-storey scheme is worth pursuing, we build the argument in the drawing set. A rear elevation shows the joint between old and new, a section shows the roof relationship, and a set of sun and daylight views tests the neighbours' rooms. Materials are named on the elevation, not left to a later condition.

We also advise a pre-application enquiry for a rear two-storey scheme, as the SPD recommends. The drawings prepared for it are the same set we later submit, so no work is lost if the officer's response is positive.

Article 4 directions and Lewisham's heritage

Lewisham has 57 Article 4 directions across 89 areas, 30 conservation areas and 367 listed building entries. A direction removes some permitted development rights, so an address inside one can need a planning application for work that would otherwise go ahead.

Inside a conservation area: No rear extension of more than one storey under PD on article 2(3) land. The borough-wide overview is at architectural drawings in Lewisham.

Permitted development for a second storey

The national rule is: Over one storey: max 3 m beyond the original rear wall and not within 7 m of the rear boundary. With so many directions in force, check the address first. If it is clear, a lawful development certificate in Lewisham records the position in writing.

Conditions follow the rule. 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.

Upper-floor safety and party wall notices

A new 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 a shared wall: Party structure notice at least 2 months before work. Where excavation is close to a neighbour: Adjacent excavation notice at least 1 month before work: within 3 m and deeper than the neighbour's foundations, or within 6 m and cutting a 45° line from their foundations.

Lewisham's householder decisions

Lewisham decided 578 householder applications in its latest published year and granted 89.4 per cent, deciding 95.2 per cent on time. The figures cover every kind of householder scheme, so we use them for timing only.

Pre-application advice and how we prepare for it

Lewisham's SPD suggests asking the council before a two-storey rear scheme is submitted, and it is advice worth taking. An officer's early view tells you whether the design argument lands, and it can save a refused application. We prepare a short set for that stage: plans, a rear elevation and a section, with the key neighbour relationships marked.

If the response is positive, the same drawings become the application with the detail added. If it is negative, the drawings show where a side extension or a single-storey rear scheme would do the job instead, so the money spent has not been wasted.

Owners often ask whether a side extension is easier. Under the SPD it is more predictable, because it comes with set-in and set-back figures, but it has its own risks: the house next door may have flank windows, and a wall built to the boundary needs the greater set-back from the front. We run both options on the model and show you which one the plot supports.

What you receive and what it costs

The set covers both floors, the roof in section, elevations and plot plans, with extra views where the design case needs them. It starts at £1,295 with VAT included, fixed before you commit, and we redraw free until approval if changes are asked for.

For simpler options see side return extension drawings in Lewisham or rear extension drawings in Lewisham. Nearby, Greenwich and Bromley follow different local rules.