Two-storey extensions for end-of-terrace houses in Northamptonshire
Looking for two-storey extensions for end-of-terrace houses in Northamptonshire? We handle the full job: survey, design, approvals, structural design and build.
Northamptonshire at a glance
- Nation
- England
- Price region
- East Midlands
- Postcode areas
- LE, NN
- Towns covered
- 9 listed below, plus surrounding villages
- Approval route
- Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
- Site visits
- Free, no obligation
What a two-storey extension for an end-of-terrace house involves
This service suits you if you own an end-of-terrace house with land to the side or a reasonable rear garden.
The main places we list in Northamptonshire are Northampton (NN1), Corby (NN17), Kettering (NN14), Wellingborough (NN8), Rushden (NN9) and Daventry (NN11). We cover the villages in between too.
Guide price in the East Midlands
Guide prices for two-storey extensions for end-of-terrace houses in the East Midlands are around £2,010–£2,700 per m² of new floor space, including VAT. For a typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that's roughly £84,500–£113,000. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.
| Spec | Per m² | Typical project |
|---|---|---|
| Essential | £1,850–£2,480 per m² | £77,500–£104,000 |
| Standard | £2,010–£2,700 per m² | £84,500–£113,000 |
| Premium | £2,410–£3,230 per m² | £101,500–£136,000 |
Rules in England
In England, a two-storey side extension on an end-of-terrace house always needs planning permission, costing £548 (or £575 for applications made from 8 December 2026). A two-storey rear extension can be permitted development within 3 m of the original rear wall and 7 m from the rear boundary. On a corner plot, nothing can go beyond a side wall that fronts a highway under permitted development.
Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.
Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.
The Party Wall etc. Act 1996 applies, so notices may be needed for work on or near a shared wall or boundary.
Getting the design right
Continuing the terrace roof
A side extension on an end-of-terrace house usually continues the roofline of the row, so the pitch, eaves height and tiles must match. A small step down in the ridge and a set-back at the front often help the extension read as an addition rather than an extra house.
Corner plots
Many end-of-terrace houses sit on corners, where the side wall faces a road. In England nothing can be built beyond a side wall that fronts a highway under permitted development, and councils guard open corners, so we keep a gap to the pavement and design the side wall as a second front.
How we work in Northamptonshire
Understand the brief
At your home in Northamptonshire we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Engineer it
Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.
Build and sign-off
Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.
Towns we cover in Northamptonshire
Two-storey extensions for end-of-terrace houses in Northamptonshire: questions
How much does a two-storey extension for an end-of-terrace house cost in Northamptonshire?
In the East Midlands our guide is £2,010–£2,700 per m² including VAT, so about £84,500–£113,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Essential and Premium specs move that by roughly 8% down or 20% up.
Can I build a two-storey side extension on a corner plot?
Often, but it needs planning permission and careful design. Councils protect the openness of corners and the view along the road, so they usually expect a gap to the pavement, a set-back from the front and a side wall with windows rather than a blank wall. We check local guidance and nearby examples first.
Will my end-of-terrace extension look like a new house on the end?
It should not, if it is designed well. A slightly lower ridge, a set-back from the front wall and a different front door position help it read as an extension. Councils often ask for this to avoid an extension that looks like an extra terraced house.
Can an end-of-terrace house have a wraparound extension?
Yes, if there is room to the side and rear. It combines a side extension over the open plot with a rear extension, and it always needs planning permission in England. It gives a large open-plan ground floor, but it also affects the attached neighbour and the street, so we test it carefully.
Will I need planning permission in Northamptonshire?
Northamptonshire is in England. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Neighbouring areas
- Two-storey extensions for end-of-terrace houses in Rutland
- Two-storey extensions for end-of-terrace houses in Leicestershire
- Two-storey extensions for end-of-terrace houses in Bedfordshire
- Two-storey extensions for end-of-terrace houses in Warwickshire
All extension services in Northamptonshire · About two-storey extensions for end-of-terrace houses
Ready to see what a second storey could do for your home?
Book a free site visit. We'll look at your house, talk through options and explain the approvals you'd need, then price the design stage in writing.