Formby, Merseyside
Rear extension planning drawings in Formby
Measured survey, design options, planning drawings and the application, handled for you. If you live in Formby and want to know what a rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Formby and its postcode districts L37 and L38 are part of our Merseyside coverage. Planning applications in Formby go to the local planning authority covering Formby, 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 Formby?
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 Formby?
Planning for a rear extension in Formby follows the English householder rules.
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
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. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Formby like to extend?
Stone and brick terraces are common around Formby. Where houses back onto a ginnel or alley, deliveries can come in from the rear, which makes the build tidier.
How a rear extension in Formby comes together
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.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
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 Formby
Close by, we work in Maghull, about 6.0 miles away, and Southport, about 6.5 miles away.
- Rear extension planning drawings in Maghull
- Rear extension planning drawings in Southport
- Rear extension planning drawings in Bootle
- Rear extension planning drawings in Litherland
- Rear extension planning drawings in Ormskirk
Other work in Formby:
FAQ
Rear extension planning drawings questions in Formby
Do I need planning permission for a rear extension in Formby?
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.
What if planning is refused?
We review the reasons with you, amend and resubmit (often free of a second fee within 12 months in England) or appeal.
Do you handle building control in Formby?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
How long does a rear extension take to build in Formby?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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.