London Townhouse Renovation Cost Guide 2026

One of the most common questions from renovation clients is: what will it cost? The answer is always: it depends. But that answer, while true, is not useful. Here is a more detailed breakdown of renovation costs for a London townhouse in 2026 — honest numbers based on current market conditions.

The property assumed

This guide uses a four-storey Victorian terraced townhouse in inner London as the reference property: - Four floors (basement or lower ground, ground, first, second) - Approximately 180–220 m² net internal area - Located in a conservation area (planning permission required for most external works) - Not individually listed - Current condition: habitable but not recently renovated; original or older-generation services

Scope categories and what they include

Cosmetic refurbishment: £70,000–130,000

Replace decoration and finishes throughout — new paint, new floor finishes (refinish existing timber, or new engineered timber), new kitchen (mid-range fitted), one or two new bathrooms, lighting updated, minor joinery repairs. No structural works, no planning permission, minimal M&E.

Programme: 10–16 weeks.

This scope is appropriate for a property in sound structural condition where the brief is to update the appearance and functionality without significant capital expenditure.

Full refurbishment: £200,000–350,000

Everything in cosmetic refurbishment, plus: full rewire, full re-plumbing, new boiler/heating system, new kitchen (quality specification), all bathrooms replaced (3–4 bathrooms), sash windows repaired and draught-proofed, structural repairs as needed (but no structural alterations). Building Regulations for electrical and plumbing works.

Programme: 20–28 weeks.

This scope is the minimum for a property where the services are original or near-end-of-life, and the objective is to produce a fully functioning, high-quality home that will not require significant works for 15–20 years.

Full renovation with structural alteration: £400,000–700,000

Everything in full refurbishment, plus: structural alterations (ground floor open plan, loft conversion, rear extension or side return infill), planning permission and associated fees, structural engineering, party wall agreements. High-quality kitchen and bathrooms.

Programme: 30–44 weeks from planning to completion.

This scope is appropriate where the objective is to reconfigure the spatial layout of the house — creating an open-plan kitchen-living space, adding a bedroom in the loft, or expanding the ground floor footprint.

Luxury renovation: £700,000–1,400,000+

Everything above, plus: luxury specification throughout (bespoke joinery, natural stone floors and bathrooms, specialist wall finishes, bespoke lighting design), interior design fees, basement conversion or substantial extension, lift installation, full AV/security/automation system, landscaped garden.

Programme: 44–72 weeks from planning to completion.

This scope represents the full renovation of a prime London townhouse to a standard that is competitive with new-build luxury residential developments.

Key cost drivers

Kitchen specification: A fitted kitchen from a mid-market supplier (John Lewis, Wren, Howdens) costs £15,000–30,000 installed. A bespoke kitchen from a quality independent maker costs £40,000–120,000 installed. The kitchen is typically 15–25% of the total budget in a full refurbishment.

Bathroom count and specification: A bathroom renovation ranges from £12,000–15,000 (good quality, mid-spec) to £35,000–70,000 (luxury specification, stone and bespoke fittings). A four-storey townhouse typically has 3–4 bathrooms.

Structural alteration: Opening up the ground floor and inserting structural steel typically costs £25,000–50,000 depending on complexity and span. A loft conversion (non-structural, no dormer) adds £60,000–100,000. A rear extension (3–4m) adds £80,000–150,000.

M&E: A full rewire of a four-storey townhouse costs £20,000–35,000. Full re-plumbing costs £15,000–25,000. A new gas boiler and heating system costs £8,000–15,000. These are non-negotiable in any full renovation of a period property.

Finishes and decoration: Decoration (paint and wallpaper) for a four-storey house: £15,000–30,000 for good-quality finish. Flooring (engineered timber throughout): £20,000–40,000. Stone in hallway and bathrooms: add £15,000–40,000.

Professional fees: a realistic allowance

Professional fees on a London renovation project:

Total professional fees for a full renovation are typically 12–18% of the construction cost. They are not optional extras — they are the means by which the project is designed, consented, and managed correctly.

VAT

The standard rate of VAT (20%) applies to renovation works on an existing dwelling. This is a significant cost that is often overlooked in initial budget planning. A £400,000 renovation (ex-VAT) costs £480,000 with VAT. On a project where the client is not VAT-registered and cannot recover VAT, the gross figure is the true cost.

There are specific VAT relief provisions (5% reduced rate) for some works including the installation of energy-saving materials. These are narrow reliefs and should be confirmed with a VAT-qualified adviser before assuming they apply.

Contingency

Every renovation budget should include a contingency of 10–15% of the construction cost. In a period property where unforeseen conditions are probable, 15% is the appropriate minimum. The contingency is not a budget for variations or upgrades — it is insurance against the cost of discovering what is behind walls and under floors.

A renovation that finishes within budget is almost always one where the contingency was drawn on. A renovation that finishes on budget without contingency is one where costs were managed tightly against a realistic number.

ASAAN's advice

The most important number in any renovation budget is not the headline construction cost — it is the total all-in figure including professional fees, VAT, and contingency. A project estimated at £400,000 construction cost will likely land at £550,000–600,000 all-in.

If you are planning a renovation and want to understand the realistic total cost for your specific property and brief, contact us for an initial cost assessment.