Planning permission for extensions across Watford
For Watford homeowners we handle planning permission for extensions, with fees agreed in writing before any work starts.
- Guide price in WatfordFrom £350 inc VAT
- PlanningWe find the right route for you
- Timescale8–13 weeks typical decision period
- Postcode districtsWD1, WD2, WD17, WD18, WD23
Planning rules that apply in Watford
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.
The planning position for a specific Watford address depends on its history and any designations, which is why we check it at the first visit.
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.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
Extensions in and around Watford
Our survey diary covers Watford, including WD1, WD2, WD17, WD18, WD23, WD24. The same team covers Bushey (2 miles), Rickmansworth (4 miles), Borehamwood (5 miles), St Albans (7 miles), all within easy reach.
The East of England mixes market-town terraces, inter-war semis and modern estates. Clay soils are common in parts of the region, which can affect foundation design.
What it costs in Watford
These are guide fees for Watford, adjusted for East of England (×1.06) and including VAT. Council application and inspection fees are paid separately.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Permitted development confirmed in writing (certificate or notification) | £350 – £700 |
| Standard | Householder planning application handled | £600 – £1,200 |
| Premium | Application with heritage or design statements, and responses to the council | £950 – £1,700 |
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.
Want a range for your exact size? The guide-price tool takes about a minute.
When it helps
- Anyone unsure whether their extension needs permission
- Projects in conservation areas or with previous refusals
- 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.
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Common questions in Watford
How long does this take for a Watford home?
8–13 weeks typical decision period, depending on the council and the complexity of the project.
Do you cover all of Watford?
Yes. We cover Watford and the surrounding parts of Hertfordshire. Site visits are free and there is no obligation.
Do I need building regulations approval in Watford?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
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.
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.
Book a free site visit in Watford
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.