Letchworth Garden City, Hertfordshire
Two-storey rear extension in Letchworth Garden City
We plan and build two-storey rear extensions for homeowners in Letchworth Garden City. A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Start with a free site visit, then a written price once the design is agreed.
Letchworth Garden City is covered from our Hertfordshire round, including SG5, SG6 and SG7. In Hertfordshire we check the neighbours' rear windows first, because the upper floor is where most two-storey schemes win or lose planning.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a two-storey rear extension cost in Letchworth Garden City?
For Letchworth Garden City we work from the East of England rate: £1,910–£2,860 per square metre of new floor, including VAT, standard specification. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £57,000–£86,000 |
| 4 m × 6 m footprint, two floors (48 m²) | £91,500–£137,500 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a two-storey rear extension in Letchworth Garden City?
Here is how the rules in England apply to a two-storey rear extension in Letchworth Garden City.
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.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
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 two-storey rear extension in Letchworth Garden City comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Two-storey rear extensions near Letchworth Garden City
From Letchworth Garden City, the nearest places we also cover are Baldock (1.7 miles) and Hitchin (3.2 miles).
- Two-storey rear extension in Baldock
- Two-storey rear extension in Hitchin
- Two-storey rear extension in Henlow
- Two-storey rear extension in Stevenage
- Two-storey rear extension in Biggleswade
Other work in Letchworth Garden City:
FAQ
Two-storey rear extension questions in Letchworth Garden City
Do I need planning permission for a rear extension in Letchworth Garden City?
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.
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.
Can it be built on a terraced house?
Sometimes, but the upper floor is harder to get through planning on a terrace because of the effect on neighbours. A single-storey extension with a loft conversion is often an easier route.
Can you match the brick or stone on my Letchworth Garden City house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
How much does a two-storey rear extension cost in Letchworth Garden City?
As a guide, £1,910–£2,860 per square metre including VAT for a standard specification. For example, 3 m × 5 m footprint, two floors (30 m²): about £57,000–£86,000 at that rate. Your written price follows the survey.
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.