Kitchen Extensions Harlesden

A kitchen extension in Harlesden is usually a job on a late-Victorian railway workers' terrace, because 15% of homes here are terraced houses and only 3% are semi-detached or detached. That points to a side return infill or a single storey rear addition across the back of the house. With 83% of homes in Harlesden being flats, many owners here hold a flat rather than a house, and a flat has no householder permitted development rights, so any extension there starts with a planning application to Brent Council.

In Harlesden, 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 Harlesden: 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.

Which kitchen extension suits a Harlesden terrace

The side return infill suits a Harlesden terrace best, because the narrow alley beside the back addition is dead space that can become kitchen floor. On a terrace that alley usually meets a neighbour's wall on the boundary, so the new wall, the gutter detail and the glazed roof all sit tight to the line. Building on or near that line brings in the Party Wall etc. Act, and you, as the building owner, serve the notices before work starts.

A wraparound, which fills the side return and runs across the rear as well, gives the largest open kitchen but adds a corner post and more steel. Semi-detached and detached houses are only 3% of homes in Harlesden, so a wide rear extension on a detached plot is the rare case here. For most terrace owners the choice is between a side infill that keeps garden and a wraparound that trades garden for a full width room.

Housing in Harlesden

Harlesden has around 6,350 homes on the Council Tax list: 18% post-war, 4% interwar and 78% predate 1919, with 83% flats and 17% houses. Where most homes are flats, only a ground floor flat in Harlesden with its own garden can extend its kitchen.

How far back Brent will let a rear extension go

Brent's Residential Extensions and Alterations SPD says a single storey rear extension to an attached home can be up to 6 metres deep from the original rear wall. That is the upper limit the council's design guidance works to for a Harlesden terrace. It is a ceiling, not an entitlement, because the effect on the neighbours still decides the depth. A later lean-to or conservatory does not move the starting point, so your designer measures from the original line before drawing anything.

Permitted development gives a smaller allowance on its own terms. For any house other than a detached one, a single storey rear extension can go 3 metres beyond the original rear wall without an application. Through the prior approval route, outside designated land such as a conservation area, that rises to 6 metres, and the height limit is 4 metres. Which route fits depends on your depth, your height and the status of your street.

Side infills in the Harlesden Conservation Area

If your house sits inside the Harlesden Conservation Area, designated in March 1994, a side extension needs householder planning permission, because permitted development does not cover side extensions on designated land. A side return infill counts as a side extension for that test. That adds the planning stage to the front of your programme, so the drawings, the roof profile and a clear description of brick, glazing and flashing materials come first.

Brent's residential conservation areas also carry article 4 directions, which take away further permitted development rights. Under those directions work such as replacing roof tiles, removing chimneys or putting up sheds and outbuildings in a rear garden can need permission. On a kitchen extension that matters when the roof covering over the back addition is being renewed, or when a new garden store is planned beside the room, so check your street's status with your designer first.

Drains, steel and building control behind a Harlesden house

Drainage decides the building control route before anything else. Brent requires a full plans application for an extension built over, or within, three metres of a public sewer, and behind a terrace the shared run often crosses the back yard. A CCTV drainage survey early on tells you whether a build over agreement, and diversion or protection of the pipe, must go into the programme before the footings are dug and the concrete ordered.

Opening the back of the house for the new kitchen means a steel beam across the old rear wall, sized by the structural engineer we appoint and placed on padstones. With full plans approval Brent usually issues an Inspection Service Plan listing the stages its inspector wants to see, and we build the programme around those visits. The units, worktops and appliances then follow in the same sequence once the shell is weathertight and first fix is in.

• Airbrick ducts to keep existing timber floors ventilated
• Soil stack and gully rerouting beneath the new floor
• Island units with power and waste run through the slab

VOA Council Tax stock of properties, March 2025, for Harlesden. Counts rounded by the VOA.

If this is your first project in Harlesden, these are worth a look: kitchen renovation in Harlesden, kitchen extensions across Brent, fitting the kitchen itself, party wall notices for a kitchen extension, how we handle kitchen extensions across London and Renovating a Victorian Terrace.

Why Harlesden Homeowners Choose GS Renovation

We plan a Harlesden kitchen extension from the boundary and the drains inwards, then run the build and the kitchen fit-out as one programme with one team. Abdelaaziz Saaid, our founder, brings more than thirty years of hands-on building to how the steel, the glazing and the finishes meet. We build to your approved drawings, bring in the structural engineer we appoint for the beam design, and keep you updated at every inspection stage so the kitchen is ready to use as soon as the room is signed off.

• Fully insured, with cover in place on every site
• One contract for the groundworks, the steel and the kitchen fit
• Kitchen layout agreed before the foundations, so the services land in the right place

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.