Whole House Renovation Costs in London: A Realistic Guide for 2026

A whole house renovation is not a single project — it is a programme of works spanning multiple disciplines, spread across weeks or months, requiring coordination between architects, structural engineers, planning consultants, and a wide range of specialist trades. In London, where properties are older, regulations are stricter, and labour costs are higher, the budget required to do this properly is substantial.

This guide sets out realistic cost ranges for 2026, explains what drives the price, and gives you a framework for planning your budget before you commission anyone.

What counts as a whole house renovation?

For the purposes of this guide, a whole house renovation means a full refurbishment of a residential property — typically covering:

• —Structural works (removing or modifying walls, new openings, lintels)
• —Full mechanical and electrical overhaul (new wiring, new plumbing, heating system)
• —New kitchen and bathrooms
• —Flooring throughout
• —Decoration throughout
• —Windows and doors (sometimes)
• —Extensions or loft conversions (sometimes — these add significantly to scope and cost)

We are not talking about a cosmetic refresh — new paint and carpets. We are talking about a substantive intervention in the fabric of the property.

Budget ranges for London, 2026

These figures are all-in estimates for the renovation works themselves, excluding VAT, professional fees (typically 10–15% of build cost), and any land or purchase costs:

These are broad ranges because the variables are significant. A property that needs full re-wiring and re-plumbing from scratch costs more than one with serviceable services. A listed building costs more than an unlisted one. A prime Mayfair address with access constraints costs more than a straightforward semi in Wandsworth.

What drives the cost

Structural condition — older London properties (Victorian, Edwardian, Georgian) often reveal structural issues once work begins: inadequate foundations, rotted timbers, previous alterations that were not properly built. A realistic contingency — we recommend 15–20% on a full renovation — exists precisely for this reason.

Services overhaul — in most properties over 30 years old, a full renovation requires complete re-wiring and new plumbing throughout. This alone can account for £40,000–£100,000 depending on property size.

Specification level — the gap between a "good" specification and a "premium" specification is enormous. Bespoke cabinetry vs off-the-shelf, stone vs ceramic tile, underfloor heating vs radiators, smart home integration vs standard switches. The specification decisions made in the first weeks of a project shape the entire budget.

Listed building status — listed buildings cost 20–35% more than equivalent unlisted properties for the same scope of work. Heritage materials, conservation-specialist tradespeople, and extended planning timelines all add to cost.

Access and logistics — inner London properties often have constrained access: narrow streets, no rear access, basement works, neighbouring properties on all sides. Scaffold, crane lifts, and temporary protection all cost money and time.

Programme — a faster programme costs more, both because it requires more resources on site simultaneously and because rush orders on materials carry a premium.

Professional fees

Build costs are only part of the total project cost. For a full renovation, professional fees typically add 10–15% on top:

• —Architect: 6–10% of build cost for full service (concept to completion)
• —Structural engineer: 1–3%
• —Planning consultant: 1–2% (where planning is required)
• —Party wall surveyor: flat fee, £800–£3,000 depending on scope
• —Interior designer: 5–15% of procurement value, or fixed fee, for full service

At ASAAN, we provide architectural, interior, and project management services in-house — which simplifies the process and gives clients a single point of accountability.

Phasing and staging

Many clients choose to phase a whole house renovation — completing the essential structural, services, and external works in phase one, then returning to higher-specification finishes later. This can spread cost and make a large project more manageable.

Phasing only makes sense if the phases are properly planned from the outset. Trying to retrofit a phase two into a property that was not designed to receive it almost always costs more than completing the work in sequence.

Timeline

A whole house renovation in London typically takes:

• —3–4 months: design and planning (longer if planning permission is required)
• —2–3 months: party wall, procurement, pre-construction
• —4–8 months: construction, depending on scope

Total timeline from initial brief to completion: 9–15 months for a straightforward renovation; 18–24 months for a complex project involving listed building consent, basement work, or significant extensions.

Getting the budget right

The most common mistake we see is owners commissioning an architect before they have a clear sense of their budget. Design work then proceeds in a vacuum, and the scheme that emerges — once costed — is often far beyond what the client intended to spend.

The right approach is to have an honest budget conversation first. At ASAAN, our initial consultations are built around this: we visit the property, understand the brief, and give the client a realistic view of what their aspiration will cost — before any design fees are committed.

If you are planning a whole house renovation in London, we are happy to visit and give you an honest assessment. Contact us or view our portfolio to see the scale of projects we have delivered.