Planning permission for extensions across Marlow
For Marlow homeowners we handle planning permission for extensions, with fees agreed in writing before any work starts.
- Guide price in MarlowFrom £350 inc VAT
- PlanningWe find the right route for you
- Timescale8–13 weeks typical decision period
- Postcode districtsSL7
What it costs in Marlow
Fees below are our Marlow guide (×1.12, the South East England factor), including VAT. Council and building control fees are extra.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Permitted development confirmed in writing (certificate or notification) | £350 – £750 |
| Standard | Householder planning application handled | £650 – £1,250 |
| Premium | Application with heritage or design statements, and responses to the council | £1,000 – £1,800 |
Our handling fee only. Council fees are extra: in England from 1 April 2026 a householder application is £548, a lawful development certificate for a proposed extension £274 and a larger home extension prior approval £249. Drawings are priced separately.
Try the guide-price tool to see a range for your own size and finish.
When it helps
- Projects in conservation areas or with previous refusals
- Anyone unsure whether their extension needs permission
- Homeowners who would rather not deal with the council themselves
A lawful development certificate is not compulsory for permitted development, but it is the cleanest proof that the extension was lawful when you come to sell. We usually recommend one.
Do I need planning permission in Marlow?
In England the main routes are permitted development (ideally confirmed with a lawful development certificate, £274), larger home extension prior approval (£249, 42 days) and a householder planning application (£548, normally 8 weeks), with council fees as set from 1 April 2026.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Covering Marlow
Across SL7, we can visit, measure and advise. Nearby, we also take on projects in High Wycombe (4 miles), Gerrards Cross (9 miles), Amersham (10 miles), Chalfont St Peter (10 miles).
Maidenhead, in Berkshire, is roughly 4 miles from Marlow and also on our list. The South East has a broad mix of 1930s semis, post-war estates, newer developments and period cottages, and many houses have enough garden for a generous rear extension.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Questions answered
Will my neighbours in Marlow be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
How long does this take for a Marlow home?
8–13 weeks typical decision period, depending on the council and the complexity of the project.
Do I need building regulations approval in Marlow?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How much does planning permission cost?
In England, from 1 April 2026 the council fee is £548 for a householder application, £274 for a lawful development certificate for a proposed extension and £249 for larger home extension prior approval. Our handling fee is separate.
What happens if planning is refused?
You can revise the design and reapply, or appeal. We read the officer’s report and tell you honestly which option has a better chance.
Book a free site visit in Marlow
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.