House extension drawings in Greenwich

Houses and plots in Greenwich

48.4 per cent of Greenwich households live in a house or bungalow, and 41.1 per cent own their home.

Domestic gardens covered 23.2 per cent of the borough's land in the national Generalised Land Use Database. Where a garden has room to build into, it still needs care: a deep extension has to leave useful outdoor space and keep daylight to the neighbour's kitchen window.

We survey the existing house to a single datum and model the proposal against it, so you can see the garden, the neighbours' openings and the street frontage together before the design is fixed.

Permitted development, prior approval or an application

Under the national rules a single-storey rear extension may go 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey, to no more than 4 m high. A Lawful Development Certificate in Greenwich records that the house qualifies.

The prior approval route allows 6 m (attached) / 8 m (detached), single storey, height max 4 m; not on article 2(3) land or an SSSI. In the latest published year the council granted 82 larger home extension prior approvals and refused 76, close to an even split. The notice has to show the extension's effect on neighbours clearly, because that is the only thing the council assesses.

Conservation-area houses and anything beyond the limits need householder planning permission, drawn as in our planning drawings in Greenwich.

How Greenwich has been deciding householder applications

Greenwich decided 624 householder applications in its latest published year and granted 77.1 per cent. 94.2 per cent were decided within eight weeks or an agreed extension.

The figures describe the council across every kind of householder case, not your house. We use the figures to plan the timetable.

What the drawings include and what they cost

A Greenwich set shows existing and proposed floor plans, elevations and sections, with the location and block plans. Extension drawings start at £695 including VAT, fixed before you commit.

Every sheet is checked by a second chartered technologist before it is submitted, and if the council asks for changes we redraw at no charge until approval. The council's application fee is £548, paid separately.

Where the extension needs structure, drainage and energy detail, our building regulations drawings in Greenwich continue from the planning set.

If the work touches a shared wall or digs close to a neighbour's foundations, the Party Wall Act applies: 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. The design must also meet the energy rules in Approved Document L: New elements in existing dwellings, limiting U-values W/(m²·K): roof 0.15, wall 0.18, floor 0.18, windows 1.4 (or WER Band B), doors 1.4. Glazing is limited too: Windows, roof windows, rooflights and doors in an extension should not exceed 25% of the extension floor area plus the area of openings removed or covered. Two exemptions apply: Residential extensions and annexes can claim exemption (claim before commencement), and Householder applications are exempt from biodiversity net gain.

Other forms and nearby boroughs

For a specific shape, see rear extension drawings in Greenwich, side return extension drawings in Greenwich or loft conversion drawings in Greenwich. The borough overview is architectural drawings in Greenwich.

Nearby councils apply their own guidance. Compare house extension drawings in Lewisham, in Bexley or in Bromley.