Kitchen Extensions New Cross

In New Cross a kitchen extension belongs to the houses, and they are the smaller part of the stock: 28% of homes are houses and 25% are terraced, against 72% flats. For the Victorian terraces around New Cross Road and Telegraph Hill Park, the choice is between a single storey addition across the back and an infill of the side return. We build the foundations, the steel, the drainage and the kitchen in one sequence, working to the drawings your designer has had approved.

In New Cross, a rear kitchen extension of about 30 square metres typically costs £45,000 to £97,500 excluding VAT, or £60,000 to £100,000 for a side return (indicative London ranges, Resi, MyBuilder and Checkatrade, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in New Cross: the structural engineer we appoint designs the foundations and steel, we build the room and fit the kitchen, and a registered electrician certifies the electrics.

How deep a New Cross terrace extension can go

The depth of a New Cross rear extension is set by two tests in Lewisham's guidance, and the shorter one normally governs. Lewisham's Alterations and Extensions SPD, adopted on 24 April 2019, says rear extensions should generally be no more than 3m deep on terraced or semi-detached properties. The same SPD says an extension should never take up more than half the depth of the original rear garden or yard. Where a terrace has a short back yard, the half-yard rule can bite first.

National permitted development allows a single storey rear extension of up to three metres beyond the original rear wall for any house other than a detached one, which lines up with the SPD guide on a terrace. The other permitted development conditions still apply. Before a kitchen layout is fixed, we measure the yard from the original back wall, not from any later lean-to, and mark out the footprint on the ground with you. Cabinet runs, the island and the door to the garden are then drawn to a footprint that has already been checked.

Housing in New Cross

New Cross has around 12,080 homes on the Council Tax list: 49% post-war, 2% interwar and 43% predate 1919, with 72% flats and 28% houses. Where most homes are flats, only a ground floor flat in New Cross with its own garden can extend its kitchen.

Flats and conservation areas in New Cross need planning first

A ground floor flat in New Cross cannot extend under permitted development, because householder permitted development rules for extensions apply to houses only and not to flats and maisonettes. With 72% of homes here being flats, garden flats in converted terraces sit on the wrong side of that line for a quick extension. If your kitchen is in a ground floor flat, the extension needs a planning application from the start, and the landlord's consent under the lease is normally needed alongside it.

Conservation areas add another layer. Lewisham's Hatcham conservation area, designated in 1990, has terrace housing behind the commercial buildings on New Cross Road. In a Lewisham conservation area a flat or a house split into flats has no permitted development rights for exterior changes, so a new rear door or a widened window needs planning permission. For a house there, every side extension needs householder planning permission, and that includes a side return infill. We set the order of works around the decision rather than guessing it.

Drains and building control on a New Cross kitchen extension

The drain under a New Cross back yard can shape the extension more than the kitchen does. Lewisham's building control guidance says you must apply for a build over agreement before doing any works where your home is within 3 metres of a public drain, or 1 metre of a public lateral drain. Where Lewisham is the building control body, it also uses a full plans application for any proposal to build above or within 3 metres of a drain or sewer, so the drain decides the building control route.

We lift the inspection chamber covers and trace the run early in the survey, so the build over agreement with the sewerage company and the full plans application can go in before the programme is fixed. Lewisham's typical inspection stages include excavation, foundations, damp-proof course, drains inspection and testing, insulation and completion. We notify each stage as the New Cross job reaches it and keep the trench open until the inspector has seen the drain, so nothing is covered too early.

Roof lights, boundary walls and the kitchen fit-out in New Cross

On a New Cross side return, the boundary wall sets the ceiling line. Lewisham's SPD says extensions up to 3m long should generally be no more than 3m high on the boundary, and the Local Plan wants a residential extension to stay smaller in scale than the house it is added to. Inside, that points to a roof that rises away from the neighbour's wall, with the highest point over the worktop or island where light and headroom count.

Lewisham's SPD says roof lights should ideally be flush and never project more than 150mm above the original roof slope. That applies where the job adds roof lights to the main roof or the pitched roof of the back addition. Glazing in the new extension roof is judged as part of the extension design on your drawings. Once the shell is dry and first fix is in, the kitchen fitters follow in the same New Cross programme, so worktops are templated from finished walls.

• Utility rooms and larders at the back of the extension
• Building control inspections from footings to completion
• Island units with power and waste run through the slab

VOA Council Tax stock of properties, March 2025, for New Cross Gate, New Cross South and Telegraph Hill. Counts rounded by the VOA.

If you are weighing up options for your New Cross property, it is worth reading kitchen renovation in New Cross, kitchen extensions across Lewisham, a side return kitchen infill, the Party Wall Act on a boundary build, our London kitchen extensions page and Side Return Extension Cost.

Trusted Kitchen Extensions in New Cross

You deal with one team from the first set-out to the last cabinet handle. We work to your approved drawings, bring in the structural engineer we appoint for the steel, and give you a written programme that shows when the drains, foundations and roof are inspected. Our founder has more than thirty years of hands-on experience on structural work. A registered electrician certifies the wiring, a registered gas engineer handles any gas work, and you receive those certificates at handover.

• One contract for the groundworks, the steel and the kitchen fit
• Cooker extract taken outside through the new roof or flank wall, not recirculated
• Rated 4.9 from 31 reviews on MyBuilder

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254). Structural design is by the consulting engineer appointed to your project.