The Quick Answer
A light refresh (new kitchen, bathroom or redecoration) typically takes 6 to 8 weeks on site. A single storey rear extension usually runs 10 to 14 weeks on site, with 3 to 6 months of design, planning and party wall process before the first digger arrives. A double storey extension takes 14 to 20 weeks on site. A full structural house renovation in Medway normally takes 6 to 12 months from first idea to move-in, and that is before you account for planning delays, party wall disputes with a neighbour, or a contractor who overpromises on the start date. The single biggest driver of delay is not the building work itself, it is decisions made (or not made) before work starts: finalising your design, submitting a complete planning application, and locking in a fixed start date with a contractor who has capacity. Get those three things right and most Medway renovations finish within the ranges below.
Why is it so hard to get a straight answer on renovation timelines?
Search for "how long does a house extension take" and you will find guides that flatly refuse to give a number, because every property, every design and every planning history is different. That caution is fair, but it is not much use if you are trying to plan around a new baby, a school year, or a mortgage offer with a deadline attached.
What we can do is give you real, published ranges from industry timeline data and our own experience delivering renovations and extensions across Medway, plus the specific local factors that speed things up or slow them down here, such as which building control body covers you and what Medway Council's planning targets actually are. Treat the figures below as a realistic planning tool, not a guarantee, and ask any contractor you're considering to turn them into a project-specific programme for your address.
How long does a full house renovation take?
| Project type | Typical on-site build time | Realistic total (idea to finished) |
|---|---|---|
| Light refresh (kitchen, bathroom, redecoration, no structural work) | 6 to 8 weeks | 2 to 4 months |
| Full house renovation, no extension | 8 to 20 weeks depending on scope | 4 to 9 months |
| Single storey rear extension | 10 to 14 weeks | 6 to 12 months |
| Double storey extension | 14 to 20 weeks | 7 to 13 months |
| Whole house renovation with an extension and structural work | 20 weeks plus | 9 to 12 months, sometimes longer |
These ranges reflect published industry timeline data for UK renovation projects. The gap between "on-site build time" and "realistic total" is almost always design, planning, party wall and contractor lead time, not bricklaying. That gap is where most Medway homeowners get their timeline wrong, because they only budget for the visible building work.
How long does a single storey extension take from idea to completion?
Breaking a single storey rear extension down stage by stage:
- Design and drawings: 2 to 6 weeks
- Planning permission (if you need it): 8 to 16 weeks, though a straightforward Medway application that does not require committee referral can come in at the 8-week statutory target
- Building Regulations approval: 5 to 8 weeks, and this can usually run in parallel with planning rather than after it
- Party wall process (if a shared wall or boundary is affected): 2 months minimum from serving notice, longer if a neighbour dissents
- Builder lead time: a good local contractor with a full diary can mean several weeks or months between signing a contract and your actual start date
- On-site build: 10 to 14 weeks, made up roughly of groundworks and foundations (1 to 3 weeks), walls and structure (2 to 3 weeks), roof (1 to 2 weeks), first fix electrics and plumbing (1 to 2 weeks), plastering with drying time (around 1 week), second fix (1 to 2 weeks), then flooring, decorating and snagging
Add it all up and most single storey extensions in Medway run 6 to 12 months from the first sketch to the last coat of paint, with the visible building work itself accounting for less than a third of that.
How long does a double storey extension take?
The pre-build stages (design, planning, party wall, contractor booking) are broadly the same as a single storey project, though design can take a little longer to get the structural detail right. On site, expect the build itself to roughly double: 14 to 20 weeks, because you're repeating groundworks, structure, roofing and both fix stages at first and ground floor level. Total project time typically lands at 7 to 13 months.
How long does planning permission actually take in Medway?
Medway Council, like every local planning authority, works to a statutory target of 8 weeks for a standard householder application (13 weeks for major applications). In practice:
- The public consultation period for neighbour notification and feedback runs 3 to 8 weeks
- Applications that need input from highways or the Environment Agency can run longer
- Any request for revised drawings restarts part of the clock
- Planning permission is valid for 3 years from the date of consent, so there is no rush once you have it, but every week you wait to submit is a week added to your overall project
If your project can go through prior approval instead of a full application (for larger single storey extensions, for example), that route also runs to roughly an 8-week timescale, with the added benefit that neighbours can only object on a narrow set of grounds rather than anything they like.
What about Building Regulations and building control in Medway?
Medway is one of four councils, alongside Canterbury, Gravesham and Swale, covered by South Thames Gateway Building Control (STGBC), based in Rochester. STGBC handles Building Regulations applications, inspections and sign-off for most domestic projects in the area, and can be contacted directly on 01634 331133 to discuss what a specific project needs before you submit anything. Building Regulations approval can usually run alongside your planning application rather than waiting for it, which is one of the easiest ways to shave weeks off your overall timeline, provided your contractor or architect coordinates the two properly.
What is the party wall process and how much time does it actually add?
If your extension involves work on or near a shared wall, or excavation close to a neighbour's foundations, the Party Wall etc. Act 1996 applies, and it has fixed statutory notice periods:
- 2 months' notice for building work that affects a party wall or the boundary
- 1 month's notice for excavation work or building a new wall on the line of junction
- Your neighbour has 14 days to respond once notice is served
- If they dissent, both sides typically appoint one agreed surveyor within about 10 days, who then produces a legally binding Party Wall Award
- Work can usually start 2 months and 1 day after the award is agreed
- Notice is valid for a year and a day, so you don't lose your place if there's a short delay elsewhere in the project
A cooperative neighbour and a straightforward notice can move through this in a matter of weeks. A dissenting neighbour, a disputed boundary, or a surveyor who is slow to engage can add two months or more, on top of everything else. This is exactly the kind of delay a good contractor helps you avoid, by serving notices early and in parallel with the design and planning stages rather than after them, which is one of several reasons it's worth reading our guide on how to choose a builder for a home renovation in Medway before you commit to anyone.
What actually causes renovation delays, and how do you avoid them?
In our experience, and echoed across the industry data we reviewed for this guide, the same handful of issues account for most overrun Medway projects:
- Late design decisions: choosing tiles, fittings or finishes during the build rather than before it, which stalls trades waiting on a final specification
- Unforeseen structural issues: rot, old drainage runs, asbestos, or a chimney breast that isn't where the drawings say it is, found once walls are opened up
- Undecided or slow-to-arrive materials: bespoke joinery, specialist glazing and imported tiles commonly run 6 to 10 weeks lead time, and ordering late is one of the most avoidable causes of a stalled site
- Party wall disputes, as above
- A contractor who quotes a start date to win the job rather than one they can actually hit, then bumps you when a previous project overruns
- Weather, particularly for roof and groundworks stages, though this rarely adds more than a week or two if the programme has any slack built in
The single most effective thing you can do is finalise your design and specification before your contractor books a start date, and choose a contractor who gives you a written, staged programme rather than a vague "8 to 12 weeks, give or take." If you haven't already, our guide on choosing a builder for a home renovation in Medway covers exactly what to ask before you sign anything, including how to spot a quote and start date that are too good to be true.
Ready to put a real timeline on your project?
Every one of the ranges above depends on your specific property, your design and your planning history. The fastest way to get an accurate answer is a site visit and a proper scoping conversation with a contractor who project manages the whole job, planning and party wall notices included, rather than leaving you to coordinate everyone yourself. Our project management service is built around exactly that, and our renovations and extensions team can walk you through a realistic, written programme for your project before you commit to anything. Get in touch for a no-obligation timeline and quote.
Frequently asked questions
How long does a kitchen renovation take on its own?
A standalone kitchen renovation with no structural changes typically takes 2 to 4 weeks on site, though a full strip-out with new electrics, plumbing and flooring can run to 5 or 6 weeks. Lead times on cabinetry and worktops, often 4 to 8 weeks, usually determine your start date more than the installation itself.
Can I speed up planning permission in Medway?
You cannot shorten the statutory consultation period, but you can avoid the delays that push applications past it: submit a complete, accurate application with no missing documents, respond quickly to any planning officer queries, and where possible use the prior approval route for larger single storey extensions instead of a full application.
Do I need a party wall agreement for a single storey extension?
Only if the work affects a shared wall or you're excavating within 3 to 6 metres of a neighbour's foundations, depending on the depth of your new foundations. Many single storey rear extensions do trigger it, so it is worth checking early rather than assuming it doesn't apply.
How long does building control take in Medway?
South Thames Gateway Building Control (STGBC), which covers Medway, Canterbury, Gravesham and Swale, processes applications and inspections on a rolling basis alongside the build rather than as one upfront approval, so it rarely adds standalone time if it's coordinated properly from the start. Contact STGBC directly on 01634 331133 to check requirements for your project.
What's the fastest type of home improvement to complete?
A light refresh with no structural work, such as redecoration, a new bathroom, or a kitchen refit using standard-lead-time products, is the fastest realistic option, typically 6 to 8 weeks on site and 2 to 4 months total from idea to finish.