Letchworth Garden City, Hertfordshire
Rear extension planning drawings in Letchworth Garden City
Measured survey, design options, planning drawings and the application, handled for you. We design, get the approvals for and build rear extensions in Letchworth Garden City and the surrounding area, with one contract from the first survey to building control sign-off.
Letchworth Garden City and its postcode districts SG5, SG6 and SG7 are part of our Hertfordshire coverage. For Letchworth Garden City homes we start with a measured survey, then draw options before anything is submitted.
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 Letchworth Garden City?
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. These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a rear extension in Letchworth Garden City?
Planning for a rear extension in Letchworth Garden City follows the English householder rules.
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. 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 Letchworth Garden City like to extend?
Post-war semis and newer estates are typical of Letchworth Garden City, and many have room for a full-width extension. Shrinkable clay is common in the East of England, so foundations near trees and hedges are designed to NHBC-style depth guidance.
How a rear extension in Letchworth Garden City 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.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Rear extension planning drawings near Letchworth Garden City
Close by, we work in Baldock, about 1.7 miles away, and Hitchin, about 3.2 miles away.
- Rear extension planning drawings in Baldock
- Rear extension planning drawings in Hitchin
- Rear extension planning drawings in Henlow
- Rear extension planning drawings in Stevenage
- Rear extension planning drawings in Biggleswade
Other work in Letchworth Garden City:
FAQ
Rear extension planning drawings questions in Letchworth Garden City
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
What postcode areas do you cover around Letchworth Garden City?
Including SG5, SG6 and SG7, and the surrounding Hertfordshire area.
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.
How long does a rear extension take to build in Letchworth Garden City?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
What do rear extension planning drawings cost in Letchworth Garden City?
As a guide, £1,000–£2,500 including VAT for a single-storey rear extension and £2,000–£3,500 for a two-storey scheme, covering the measured survey, design options and the application. The council fee is extra.
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.