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Kitchen Extension Cost · Guildford

How much does a kitchen extension cost in Guildford?

A kitchen extension is one fixed build with a kitchen sitting on top of it, with the period cottages carrying more structural work than the interwar semis. Calibrated to Guildford, a typical 30 m² kitchen-diner rear runs from around £136,000 with a self-managed kitchen to £188,000 and beyond for a bespoke one — the build barely moves, and the kitchen you choose is the whole difference.

One build, four budgets — calibrated to Guildford

The build is fixed; the kitchen is the variable. For a representative 30 m² kitchen-diner rear in Guildford, the project total climbs with the tier while the base underneath never moves.

Self-managed IKEA, self-fit
£8,000 – £10,000
£136,000 – £138,000
Supplied & fitted Howdens · Magnet · Benchmarx
£14,000 – £22,000
£142,000 – £150,000
Premium Local bespoke · Second Nature / Burbidge
£23,000 – £50,000
£151,000 – £178,000
Luxe & bespoke deVOL · Tom Howley · Plain English
£60,000+
£188,000+
The fixed build base — £4,255/m² · ~£128,000 on a 30 m² rear. Foundations and slab, walls and superstructure, roof, envelope and glazing, first-fix services, non-kitchen finishes, fees and contingency — and the structural knock-through, the steel and the opening between the existing house and the new room. Identical on every tier.

Figures at the BuildLens South East baseline, priced on current trade day rates and live merchant pricing (2026). Fully loaded — fees, contingency and VAT included. Totals scale with size, and firm to your own property with a report. The full tier ladder, with what each rung buys, sits on the main kitchen extension page.

The knock-through in Guildford

Guildford kitchen extensions divide with the stock: the interwar semis take clean rear additions with straightforward knock-throughs, while the period cottages near the centre carry careful structural work in older fabric — the same project, two different build stories.

The mechanics are the same everywhere: a wall comes out, an engineer-sized steel beam goes in to carry what it held, building control signs it off, and where the wall sits on or near a boundary, a party wall matter follows. All of it is standard, all of it is predictable from the property, and all of it is carried in the fixed build base — the tier ladder above sits on top of it, never inside it.

The full ladder, rung by rung. What each kitchen tier actually buys — and why bespoke is not the top rung — sits on the main kitchen extension page. This page is the Guildford calibration of it.

Kitchen extension cost — the full ladder →

Common questions about kitchen extension cost in Guildford

How much does a kitchen extension cost in Guildford?
On a representative 30 m² kitchen-diner rear calibrated to Guildford, the fully-loaded total runs from around £136,000 – £138,000 with a self-managed kitchen, through £142,000 – £150,000 supplied and fitted, to £151,000 – £178,000 for a premium or local-bespoke kitchen, and £188,000+ for a named bespoke maker. The build base is fixed at about £128,000; the kitchen tier sets where the total lands.
Does the type of Guildford property change the kitchen extension cost?
Materially. An interwar semi takes a rear addition and knock-through predictably; a period cottage near the centre needs its structural work sized for older fabric and its making-good priced for it. Both are standard local projects — but the same headline figure lands differently on each, which is what a property-specific report resolves.
Why does the kitchen choice change the total by so much?
Because the build behind it doesn't change. The structure, roof, envelope, services and the knock-through steel cost much the same whichever kitchen goes in — so the entire spread on the same extension sits in the kitchen tier. Picturing a bespoke kitchen on a mainstream budget is where most kitchen-extension budgets come apart.

Where does your Guildford kitchen extension fit in?

The right BuildLens report depends on why you are asking.

You're ready to build
Cost the whole job, itemised by trade and calibrated to your Guildford property.
Build Cost Intelligence · from £199
You're weighing extend against move
See the maths on staying and building versus selling and buying in Guildford, before you spend on drawings.
Extend or Move · £49
You're selling, and wondering if it pays
What the work costs set against what it returns in the Guildford market, before you commit.
Homeowners Market Intelligence · from £129
You're buying a Guildford property to extend
Cost the work properly before you commit to the purchase price.
Build Cost Intelligence · from £199