The Real Timeline of a Full Home Refurbishment (and Where Delays Come From)

Ask three builders how long a full home refurbishment takes and you'll get three different answers — usually optimistic ones. The truth is that most prime London projects run longer than homeowners expect, and almost always for reasons that could have been anticipated. This is an honest look at how the timeline actually breaks down, and where the weeks quietly disappear.

The Headline Number

For a full refurbishment of a typical two- or three-bedroom prime London property — think a flat in Chelsea or a terraced house in Fulham — you should plan for four to nine months on site, depending on scope. Add structural work, a basement, or a loft conversion and you can push well beyond that.

But "on site" is the misleading part. The clock starts long before anyone lifts a floorboard.

Historic terraced housing blends with modernized flats in the Avalon Projects renovation, creating a harmonious streetscape under a clear blue sky.

The Full Timeline, Phase by Phase

1. Design and specification — 6 to 12 weeks

This is where good projects are won or lost. It covers concept design, detailed drawings, material selection, and a fully costed specification. Rushing this phase is the single most common cause of delays later, because every decision left open becomes a decision made under pressure mid-build.

Homeowners often underestimate how long selections take. Choosing every tile, tap, worktop, handle, paint colour, and light fitting for an entire home is genuinely time-consuming — and long-lead items ordered late will stall the whole programme. (For more on how we structure this stage, see our guide to what design-and-management means and why it saves you money.)

2. Planning and approvals — 8 to 12 weeks (if required)

Not every refurbishment needs planning permission, but many prime London jobs touch something that does: a rear extension, altered elevations, or works to a listed building or in a conservation area. The Planning Portal is the quickest way to check whether your specific works need consent. Both RBKC and Hammersmith & Fulham run to statutory determination periods of roughly eight weeks, and that assumes a clean application — in both boroughs, extensive conservation-area coverage and Article 4 directions mean permitted development rights are often restricted or removed.

If a party wall agreement is needed — extremely common in London terraces and mansion blocks — allow up to two months for neighbours to respond and surveyors to agree an award. This runs in parallel with other prep, but a dissenting neighbour can genuinely hold up work to the shared structure. The government's Party Wall etc. Act 1996 explanatory booklet sets out when notice must be served and how the process works.

3. Procurement and mobilisation — 2 to 4 weeks

Contracts signed, trades booked, long-lead materials ordered, scaffolding and skips arranged, building control engaged. Bespoke items — joinery, stone worktops, made-to-order windows — often carry lead times of eight to twelve weeks, so these must be ordered at the start, not when the room is ready for them.

4. On-site construction — 16 to 36 weeks

Broadly, the on-site sequence runs:

• Strip-out and structural work (2–5 weeks): demolition, removing walls, steel installation, structural openings

• First fix (3–6 weeks): everything hidden in walls and floors — plumbing runs, electrical wiring, drainage, framing

• Plastering and drying (2–4 weeks): plastering, then genuine drying time before decoration; skipping this causes cracking later

• Second fix (4–8 weeks): kitchens, bathrooms, flooring, doors, sockets, radiators, and finishing trades

• Decoration and finishing (2–4 weeks): painting, tiling completion, final fittings

• Snagging and handover (1–2 weeks): the defects list, corrections, and final sign-off

Contemporary kitchen extension by Avalon Projects, showcasing a seamless blend of modern design and functionality, perfectly integrated with the existing architecture.

Where the Delays Actually Come From

In our experience, timeline overruns rarely come from trades working too slowly. They come from a handful of predictable sources:

Late decisions. A worktop chosen in week ten instead of week two can idle a kitchen fit-out for weeks. The majority of avoidable delay traces back to specification decisions made after the build has started.

Variations and scope creep. "While the walls are open, could we also…" is the most expensive sentence in construction. Each change carries its own design, pricing, and lead-time tail — reasonable in isolation, but they compound. (This is also why your payment schedule and stage payments matter — variations should be priced and agreed, not absorbed quietly.)

Long-lead items ordered late. Bespoke joinery, stone, and imported tiles don't care about your programme. If they're ordered when the room is ready rather than at the outset, everything waits on them.

Surprises behind the walls. Older London properties hide their problems well: rotten joists, ancient wiring, undersized drainage, or structural quirks that only reveal themselves once you open up. A sensible contingency in both budget and time absorbs these; no contingency turns them into a crisis.

Approvals and neighbours. Planning conditions, building control inspections, and party wall disputes all sit partly outside your builder's control — which is exactly why they need to be started early and managed actively.

Trade sequencing and availability. Skilled prime London trades are booked well ahead. A gap in the sequence — waiting on an electrician, or a plasterer who's moved to the next job — can be hard to close at short notice.

Modern and elegant bathroom renovation by Avalon Projects featuring a sleek freestanding bathtub, sophisticated rainfall showerhead, and a stylish wooden vanity ensemble.

How to Protect Your Timeline

The projects that finish on time share a few habits. Selections are locked down before work starts. Long-lead items are ordered up front. A realistic contingency — both time and money — is built in from day one rather than negotiated in a panic. And there's a single point of accountability holding the programme together, rather than a homeowner trying to coordinate trades from their kitchen table.

That last point is the real argument for a managed design-and-build approach. When one team owns the design, the procurement, and the site programme, the handoffs that usually cause delay simply don't exist in the same way.

Modern kitchen design by Avalon Projects featuring dark wood cabinetry, a marble backsplash, and a cozy wood-burning stove with stacked logs for a rustic touch.

The Honest Summary

A full prime London refurbishment is realistically a six-to-twelve-month commitment end to end, once you count design, approvals, and the build itself — not the "we'll have you back in by Christmas" figure that gets quoted to win the job. A builder who gives you a realistic timeline up front is showing you respect, not a lack of ambition.

If you'd like a considered, honest timeline for your own project, get in touch — we're always happy to talk it through before any commitment.

Avalon Projects is a design-and-build firm working across prime and South West London, including Chelsea, Fulham, and Kensington. See our recent projects or read more from the journal.