How long does planning permission actually take?

The statutory period is 8 weeks for a householder application, which is the kind used for works to a single home. It is counted from when the council validates the application, meaning when it confirms the application is complete, not from when you submit. But 8 weeks is a floor, not a ceiling. Official figures show most applications now rely on an agreed extension of time, so longer is normal in prime London. Listed building consent runs in parallel, on the same 8-week target.

When can we actually move back in?

Practical completion, the point at which the builder finishes the work, is not the same as moving back in. Between the two sit the snag list, the commissioning of the heating and services, meaning getting them tested and running properly, and the building-control completion certificate, which is the sign-off that the work meets the regulations. Allow a few weeks between the builder finishing and you moving in.

Do we have to move out during the work?

For a full back-to-brick renovation, living in the house is usually impractical, and often unsafe, so most owners move out for the build. That matters for the timeline in a specific way. The period you are displaced is the build plus the few weeks until move-in, not the whole end-to-end programme. The design and consents happen while you are still in your current home.

Does a basement add much time?

Yes, and more than any other single factor. A basement typically adds around 3 to 6 months on top of a whole-house renovation above it. As a standalone project, a basement runs around 14 to 18 months, because it needs its own basement impact assessment, the engineering report on how the dig affects the building and its neighbours, and a longer planning and build sequence.

Is the timeline different for a flat?

Yes. A flat usually needs the freeholder's licence to alter, the landlord's written consent to the work, before the structure is touched, and getting it adds time. And a flat in a tall mansion block can fall under the Building Safety Regulator's Gateway 2 approval, a building-control sign-off that must be obtained before work starts, which adds more. A flat renovation is a different timeline from a house.

How Long Does a Full House Renovation Take in London?

The honest answer: two timelines, not one

When people ask how long a renovation takes, they mean the build. But the build is not the long part, and it is not the real question. The real question is how long it takes from the first design meeting to moving back in, which is a much larger number. This answer gives both, because the honest version needs two.

End to end, a full prime-London house renovation usually takes around 14 to 22 months, from the first design meeting to moving back in. The build itself, the time on site, is usually around 6 to 10 months for a whole-house refurbishment without a basement. Those are the two numbers, and most confusion comes from quoting one and meaning the other.

The conflation is easy to fall into. People quote the build figure, because it is the part they picture, and leave out the months of design, planning and procurement that come before anyone arrives on site. Those ranges are what industry guidance and practitioners typically cite, not promises, and your own project can sit above or below them.

Scope is what moves the number most, so it is worth pinning down. A full renovation here means replacing the structure where needed, the services (the wiring, plumbing and heating) and the finishes throughout, often stripping the house back to brick. That is a different job from a cosmetic refresh of paint, flooring and a new kitchen, which is measured in weeks, not months. When you read a timeline, check which one it is describing, because the two are not comparable. Knowing both numbers up front is what lets you plan the rest of your life around the work, rather than discovering halfway through that the end is much further off than the build figure suggested.

Where the time actually goes

The end-to-end number is the sum of several phases, and seeing them laid out shows why it is large. Here is how a typical full renovation breaks down.

Phase	Typical duration	What happens
Brief and feasibility	1 to 4 weeks	Site visit, working out the constraints, and a budget reality-check
Design (concept to technical drawings)	2 to 6 months	Layouts first, then detailed drawings, structural calculations and full specifications
Planning and consents	8 weeks at minimum, often longer	The council's decision, which runs between the design stages
Procurement and tender	4 to 8 weeks	Pricing the job and appointing the builder
Construction (the build)	6 to 10 months	Longer with a basement or major structural work
Handover and snagging	2 to 6 weeks to move-in	Finishing, final checks and working through the snag list

A few of these run alongside each other rather than strictly in sequence, which is the only reason the total is not even longer. Procurement, which is the process of pricing the work and appointing a builder, often overlaps the tail of design. Planning sits between the design stages rather than after them. Snagging, which is the list of small faults found at the end and put right, can begin before the very last finishes are done. But the design, the consents and the build each still take the months shown, and they cannot all be collapsed into one. Read the table as a guide to the shape of the work, not a fixed schedule, since your own phases will shift around these depending on the house and the scope.

Why the front end takes as long as the build

Add up the phases before the build and a pattern appears: the design, the consents and the procurement together come to as much time as the build itself, and sometimes more.

It helps to think of two clocks. The first is the time it takes to even start on site, which once you include design and consents is often 8 to 12 months. The second is the time on site, the build, at 6 to 10 months. For a full prime-London house renovation, the first clock usually equals or beats the second. The part you cannot see lasts as long as the part you can.

The reason is simple, and none of it is wasted. Detailed design and structural calculations take real time, because the drawings have to be complete and correct before anyone prices or builds from them. The council's decision takes real time, because that is how long the process runs, and that is the nature of the work rather than anyone being slow. A proper tender takes real time, because pricing a back-to-brick renovation accurately is not a quick exercise. None of this front-end work is visible from the street, which is exactly why it surprises people. It is happening; it just is not happening on site. The practical lesson is to budget time for the front end from the outset, because the owners who are surprised are usually the ones who counted only the build.

What makes it longer

The ranges above assume a reasonably clean run. Several things commonly stretch them, and it is worth knowing which.

A planning refusal is one of the largest. If the council refuses and you resubmit, you effectively restart the decision clock, and you usually redesign first, so a refusal can add several months.

Listed building or conservation-area scrutiny adds time in a quieter way. A listed building is one protected for its special architectural or historic interest, and a conservation area is a district whose character the council protects. Either brings extra design rounds, and a listed building needs a separate listed building consent that has to be obtained alongside planning. This is common in prime London: conservation areas cover nearly three-quarters of Kensington and Chelsea, and around three-quarters of Westminster, so most central houses sit inside one.

A basement is the single biggest addition to the programme of any factor here. It changes both the consents and the build, and it is covered in the FAQ below.

A party-wall dispute can also add time. A party wall is one you share with a neighbour, and working on it means serving notice first. If the neighbour dissents from that notice, surveyors are appointed and an award is agreed before the affected work can start, which is a process with its own timetable.

Long-lead items are a frequent and underrated cause. Bespoke joinery and glazing, the items made to order rather than bought off the shelf, can take 12 to 20 weeks or more to manufacture, and they often sit on the critical path, meaning the whole job waits on them.

The most common single cause of overrun is none of these. It is the old building itself. Unforeseen structural condition, found once you open up a Victorian or Georgian house, is the classic surprise, which is why a sensible programme carries a time contingency rather than assuming a clean run. These factors also stack: a listed house with a basement and a dissenting neighbour carries several at once, and the additions are cumulative rather than alternatives. Each one you can see coming is one you can plan around; it is the surprises that hurt, which is the whole argument for building slack into the programme from the start.

The honest version

The trade has every reason to answer how long with the build figure. It is the short, comfortable number, and the short number wins the job. The long front end stays quiet until the client is living it. The industry, Myrmex included, has been happy to quote the comfortable number and let the design and consents surface later as a surprise. The honest answer counts from the first design meeting, not the first day on site. That single shift, in where you start counting, is the difference between a timeline you can rely on and one that disappoints.

There is also a real way to make the total shorter, and it is structural, not a matter of rushing. You do not have to run the phases strictly one after another. Bringing the builder in early, through a two-stage tender, lets the build planning and procurement run alongside the design and consents instead of after them. A two-stage tender uses a Pre-Construction Services Agreement, an early appointment under which the contractor advises on buildability, programme and long-lead ordering before the main build contract is signed. Done well, it compresses the overall timeline without compressing the build itself, which is the part you do not want to rush. It is one of the clearest advantages of running a project through construction management rather than a single fixed contract handed over at the end.

If you want to see how a project like this is run from the first meeting, that is the next thing to read.

This is general information and an illustrative timeline, not a project programme or a guarantee. Every house, every scope and every set of consents is different. A construction manager builds the programme around the specific project, so treat these figures as ranges, not promises.