Two-storey extensions for end-of-terrace houses in Oxfordshire

Oxfordshire at a glance

Nation: England
Price region: South East England
Postcode areas: OX, RG, SN
Towns covered: 13 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

A two-storey extension for an end-of-terrace house is a two-floor addition to the open side or the rear of the last house in a row. The side plot is often the best opportunity, because it adds width without taking rear garden. The design has to work with the terrace's roofline and the street, and any corner plot facing a road needs extra care.

Across Oxfordshire we cover Oxford (OX1), Banbury (OX15), Abingdon (OX13), Bicester (OX6), Didcot (OX11) and Witney (OX7), plus the smaller places around them.

Guide price in South East England

A guide price for Oxfordshire: around £94,500–£127,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). That works out at £2,260–£3,030 per m² of new floor space, including VAT at 20%. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

Spec	Per m²	Typical project
Essential	£2,070–£2,780 per m²	£87,000–£117,000
Standard	£2,260–£3,030 per m²	£94,500–£127,000
Premium	£2,710–£3,630 per m²	£113,500–£152,500

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.

Older walls and foundations

Many terraces are older, with shallow footings and solid walls. Tying a new two-storey extension into them needs a careful structural design and sometimes movement joints, and we check the gable wall and its foundations before the design is fixed.

How we work in Oxfordshire

Measure and listen
A visit to Oxfordshire to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
Design and approvals
We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.
Engineer it
Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.
Build and hand over
We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Towns we cover in Oxfordshire

Two-storey extensions for end-of-terrace houses in Oxfordshire: questions

How much does a two-storey extension for an end-of-terrace house cost in Oxfordshire?

In South East England our guide is £2,260–£3,030 per m² including VAT, so about £94,500–£127,000 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.

Are old terrace foundations strong enough to extend next to?

Usually, but they need checking. Older terraces often have shallow brick footings, and a new two-storey extension sits on deeper, modern foundations alongside them. The structural engineer designs the junction so the two can move slightly without cracking, and we dig trial holes to see what is there before the design is fixed.

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 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.

Will I need planning permission in Oxfordshire?

Oxfordshire is in England. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.

Neighbouring areas

All extension services in Oxfordshire · About two-storey extensions for end-of-terrace houses