Extension plans and drawings across Watford
Need extension plans and drawings in Watford? We survey the house, prepare what the council needs and deal with the officers until a decision is made.
- Guide price in WatfordFrom £1,250 inc VAT
- PlanningWe find the right route for you
- Timescale2–6 weeks for drawings
- Postcode districtsWD1, WD2, WD17, WD18, WD23
Fees 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 | Measured survey and planning drawings | £1,250 – £2,350 |
| Standard | Planning drawings plus building regulations drawings | £2,300 – £4,050 |
| Premium | Full pack with structural calculations and 3D visuals | £3,600 – £5,850 |
Want a range for your exact size? The guide-price tool takes about a minute.
Will the council need to approve it?
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.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
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.
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).
Local to Watford
Our survey diary covers Watford, including WD1, WD2, WD17, WD18, WD23, WD24. Nearby, we also take on projects in Bushey (2 miles), Rickmansworth (4 miles), Borehamwood (5 miles), St Albans (7 miles).
Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
Who this service is for
- Anyone who wants fixed designs before getting build prices
- Homeowners at the very start of a project
- Projects that need a planning application or other approval
What happens next
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Common questions in Watford
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Watford, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Will my neighbours in Watford 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.
Who do I contract with in Watford?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I use your drawings with another builder?
Yes. Once paid for, the drawings are yours to use for your project.
Do I need an architect?
Not necessarily. For most extensions an experienced designer or architectural technologist is enough. For listed buildings or complex sites an architect’s input can help.
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.