Luton, Bedfordshire
Semi-detached rear extension in Luton
Single or two-storey extensions for semi-detached houses, with side access and one party wall. We design, get the approvals for and build rear extensions for semi-detached houses in Luton and the surrounding area, with one contract from the first survey to building control sign-off.
Luton is covered from our Bedfordshire round, including LU1, LU2, LU3 and LU4. Semi-detached houses are common across Bedfordshire, and their side access makes rear extensions quicker to build.
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 semi-detached rear extension cost in Luton?
Guide prices for a semi-detached rear extension in Luton start from our East of England rate of £2,010–£3,290 per square metre, including VAT. 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 wide × 4 m deep (12 m²) | £24,000–£39,500 |
| 4 m wide × 5 m deep (20 m²) | £40,500–£65,500 |
| 4 m wide × 6 m deep (24 m²) | £48,500–£79,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a semi-detached rear extension in Luton?
Here is how the rules in England apply to a semi-detached rear extension in Luton.
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
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.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
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 Luton like to extend?
Luton mixes Victorian terraces with 1930s semis, so both side returns and full-width kitchen extensions suit houses here.
How a semi-detached rear extension in Luton 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.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
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.
Semi-detached rear extensions near Luton
Neighbouring places we cover include Dunstable (4.5 miles) and Harpenden (5.0 miles).
- Semi-detached rear extension in Dunstable
- Semi-detached rear extension in Harpenden
- Semi-detached rear extension in Hitchin
- Semi-detached rear extension in Codicote
- Semi-detached rear extension in Hemel Hempstead
Other work in Luton:
FAQ
Semi-detached rear extension questions in Luton
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.
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.
How far can I extend a semi without planning?
3 metres under permitted development in England, or up to 6 metres with prior approval, outside designated land.
Do you handle building control in Luton?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
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.
How much does a semi-detached rear extension cost in Luton?
As a guide, £2,010–£3,290 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £24,000–£39,500 at that rate. Your written price follows the survey.