Extension plans and drawings across Sevenoaks
For Sevenoaks homeowners we handle extension plans and drawings, with fees agreed in writing before any work starts.
- Guide price in SevenoaksFrom £1,300 inc VAT
- PlanningWe find the right route for you
- Timescale2–6 weeks for drawings
- Postcode districtsTN13, TN14
Design and approval fees for Sevenoaks
Guide fees for Sevenoaks including VAT, using our South East England factor of ×1.12. Council and building control charges are not included.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Measured survey and planning drawings | £1,300 – £2,500 |
| Standard | Planning drawings plus building regulations drawings | £2,450 – £4,300 |
| Premium | Full pack with structural calculations and 3D visuals | £3,800 – £6,200 |
For a figure based on your own dimensions, use our guide-price tool.
Working in Sevenoaks
Across TN13, TN14, we can visit, measure and advise. Neighbouring towns we cover include Tonbridge (6 miles), Swanley (9 miles), Tunbridge Wells (10 miles), Dartford (12 miles).
Orpington, in Greater London, is roughly 8 miles from Sevenoaks and also on our list. Homes across the South East range from Victorian terraces in the older town centres to large detached houses on the edges, so the right extension type varies street by street.
Planning and approvals in Sevenoaks
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.
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).
Included in a typical project
- Measured survey of the house and garden
- Structural calculations from an engineer (full pack)
- Planning drawings: existing and proposed plans and elevations, site and location plans
- Building regulations drawings and specification
- Two or three layout options to compare
From first visit to completion
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
We visit your Sevenoaks home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
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.
Questions answered
Will my neighbours in Sevenoaks 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.
Do you cover all of Sevenoaks?
Yes. We cover Sevenoaks and the surrounding parts of Kent. Site visits are free and there is no obligation.
How long does this take for a Sevenoaks home?
2–6 weeks for drawings, depending on the council and the complexity of the project.
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 Sevenoaks
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.