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Sevenoaks, Kent

Rear extension planning drawings in Sevenoaks

For homes in Sevenoaks, a rear extension is often the simplest way to gain space without moving. Measured survey, design options, planning drawings and the application, handled for you. We take it from survey to completion certificate.

Sevenoaks is covered from our Kent round, including TN13. Planning applications in Sevenoaks go to the local planning authority covering Sevenoaks, and we check its local design guidance for rear extensions before drawing.

Book a free site visit

Tell us about the house and we'll call to arrange a free, no-obligation visit.

What do rear extension planning drawings cost in Sevenoaks?

As a guide, £1,000–£2,500 including VAT for a single-storey rear extension, or £2,000–£3,500 for a two-storey scheme. A householder planning application in England costs £548 (£575 for applications made from 8 December 2026), and a lawful development certificate for proposed work costs half the householder fee. We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.

Do you need planning permission for a rear extension in Sevenoaks?

Whether your rear extension in Sevenoaks needs a planning application depends on its size, your house and any local restrictions.

England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.

Councils aim to decide householder applications within 8 weeks of validation, and prior approval within 42 days.

Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.

What are homes in Sevenoaks like to extend?

Around Sevenoaks the housing ranges from inter-war semis to 1960s and 1970s estates with good-sized gardens. Many of the newer estates had permitted development rights removed by condition, so we check the planning history before anything is drawn. For Sevenoaks homes we start with a measured survey, then draw options before anything is submitted.

How a rear extension in Sevenoaks comes together

  1. Free site visit

    We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.

  2. Design and guide price

    Two or three layout options with a guide price for each, so you choose the design knowing what it costs.

  3. Approvals

    Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.

  4. Fixed price and build

    A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.

Rear extension planning drawings near Sevenoaks

Close by, we work in Chelsfield, about 6.5 miles away, and Tonbridge, about 6.5 miles away.

Other work in Sevenoaks:

All rear extensions in Sevenoaks

FAQ

Rear extension planning drawings questions in Sevenoaks

What postcode areas do you cover around Sevenoaks?

Including TN13, and the surrounding Kent area.

Do I need a party wall agreement?

In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.

Can planning conditions affect the build?

Yes, for example matching materials or obscure glazing. We plan for them.

Do I need planning permission for a rear extension in Sevenoaks?

Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.

Can I get a price without a visit?

Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.

Will I need a structural engineer?

Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

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