Kitchen Extensions Old Street

A kitchen extension in Old Street is a rare job, and the housing count says why: 99% of homes here are flats and 1% are houses. The work that does come up is a ground floor flat with a yard or garden behind it, or one of the few terraced houses. Both start from the same point. A flat has no householder permitted development rights, and a house in a conservation area loses some of them, so the drawings and the consent come before anything else.

In Old Street, 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 Old Street: 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.

Why a flat in Old Street needs full planning for an extension

A ground floor flat in Old Street needs a full planning application before any kitchen extension, however small. Islington Council says you need to apply for full planning permission to add an extension or conservatory to a flat, and the national permitted development limits for single storey rear extensions apply to houses only. That settles the order of work. Your designer draws the scheme, you or your agent submit it, and we price from those drawings and build to whatever consent is granted.

For a flat the application is only half of the paperwork. The yard or garden behind a ground floor flat may be demised under your lease, but the walls the extension bears on and the drains it connects to normally belong to the freeholder. A licence to alter from the freeholder sits alongside the planning consent. In an ex-council block in Old Street that freeholder may be the council itself. We give the managing agent the method statement and programme they ask for, so the two approvals can run at the same time rather than one after the other.

Housing in Old Street

For Old Street the Council Tax list gives about 6,800 homes; by type 99% flats and 1% houses, by age 76% post-war, 5% interwar and 16% older than 1919. Only a ground floor flat in Old Street with its own garden can extend its kitchen, which matters here because most homes are flats.

Houses near Old Street: the few terraces and the 45 degree test

The houses that exist around Old Street are terraces, and they make up 1% of homes. Semi-detached and detached houses round to 0% on the valuation list. On a terrace the neighbours' rear windows sit close to the party line, so Islington's Urban Design Guide test matters early. If the centre of a neighbour's main rear window lies within a 45 degree angle drawn from the end of your proposed extension, the guide says its depth is likely to have an unacceptable impact.

In practice we ask your designer to plot that line on the survey before the kitchen layout is fixed. A shallower extension with the full width of glass often clears the test where a deeper one fails, and the lost depth can be won back inside by moving the sink run or taking out a chimney breast. The guide also says there will normally be scope for ground floor extensions within a lightwell or beyond the existing back addition if enough useable garden is kept. On a small Old Street yard, the garden left over is part of the test.

St Luke's conservation area and kitchen extensions off Old Street

Some of the older streets off Old Street sit in the St Luke's conservation area, which the council describes as straddling Whitecross Street and Old Street and an important surviving part of historic Finsbury. On designated land such as a conservation area, every side extension needs householder planning permission, and the larger rear extension route through prior approval is not available. Islington has also removed some permitted development rights in 40 of its 42 conservation areas by article 4 direction, so your designer should confirm what applies to your address.

That changes the specification. Islington says a house covered by an Article 4 direction needs householder planning permission to install or replace front windows or doors, so any change to the street side is drawn with the extension. The Urban Design Guide also says single storey rear extensions may suit high quality contemporary design, such as contrasting materials or a lightweight glazed form. For a kitchen that can mean a slim framed glass box or a brick base with a glazed roof, and we order the glazing only once the consented drawings fix its size, finish and frame colour.

Drains, steel and deliveries for an Old Street kitchen extension

The first site question on an Old Street kitchen extension is where the drains run. Islington Council says a building notice cannot be used when building over existing sewers and drains, or for residential premises with common areas. So an extension to a flat in a block, or one sitting over a shared run, goes through full plans with the council or a registered building control approver. We expose and survey the run early so the structural engineer we appoint can design the foundation around it and the steel that carries the opened back wall.

Getting materials in is the other constraint in Old Street. Islington requires a licence for any temporary obstruction on the highway, and on red routes such as City Road the permission comes from Transport for London instead. Steel, glazing units and the kitchen itself each come in short booked delivery windows, and the kitchen fit out follows the plastering in the same programme so you are not relying on two firms to share one yard.

• The kitchen itself fitted under the same contract as the build
• Kitchen-diner layouts planned before the foundations
• Island units with power and waste run through the slab

VOA Council Tax stock of properties, March 2025, for Old Street & St Luke's. Counts rounded by the VOA.

Once you know the scope of the kitchen extensions in Old Street, it helps to read kitchen renovation in Old Street, kitchen extensions across Islington, a wraparound kitchen-diner, the Party Wall Act on a boundary build, kitchen extensions across London and Permitted Development Explained.

Trusted Kitchen Extensions in Old Street

Old Street kitchen extensions are small in number and heavy on paperwork, so the value is in sequence. We read the consented drawings and the licence to alter before pricing, visit the yard to find the drains and access, and give you a written quotation with a programme that runs the structure, glazing and kitchen fit out as one job. The structural engineer we appoint designs the steel, a registered electrician certifies the wiring, and you deal with one team from the first opening to the last worktop.

• Kitchen layout agreed before the foundations, so the services land in the right place
• Rooflights set out against the engineer's steel layout
• Fully insured, with cover in place on every site

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.