Two-storey extensions for semi-detached houses in Hereford
Our two-storey extensions for semi-detached houses service in Hereford covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
Before you start in Hereford, here's what applies.
- Postcode districts
- HR1 and HR4
- County / area
- Herefordshire, England
- Price region
- West Midlands
- Guide price
- £56,000–£75,500 (£2,000–£2,700 per m²)
- Approval route
- Depends on position: a two-storey rear extension may be permitted development (3 m deep, 7 m from the rear boundary); a two-storey side extension needs planning permission.
- Nearest towns
- Belmont (Herefordshire) (1.5 miles), Ivington (10.6 miles), Ross-on-Wye (11.6 miles)
- First visit
- Free, no obligation
About a two-storey extension for a semi-detached house
A two-storey extension for a semi-detached house is a two-floor addition to the rear, the open side, or both, designed around the attached neighbour on one side. The rear is often the simplest option and can sometimes be permitted development, while a side extension uses the gap on the detached side. Both need care with the shared party wall and the neighbour's light.
We cover Hereford (HR1 and HR4) and the places around it, including Belmont (Herefordshire) (1.5 miles), Ivington (10.6 miles) and Ross-on-Wye.
What it costs in Hereford
Guide prices for two-storey extensions for semi-detached houses in the West Midlands are around £2,000–£2,700 per m² of new floor space, including VAT. For a typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space), that's roughly £56,000–£75,500. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.
| Spec | Per m² | A 4 m × 3.5 m footprint on two floors (28 m² of new floor space) |
|---|---|---|
| Essential | £1,840–£2,480 per m² | £51,500–£69,500 |
| Standard | £2,000–£2,700 per m² | £56,000–£75,500 |
| Premium | £2,400–£3,240 per m² | £67,000–£90,500 |
Planning and building regulations in Hereford
In England, a two-storey rear extension on a semi can be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary, with matching materials and roof pitch. A two-storey side or wraparound extension always needs planning permission, costing £548 (or £575 for applications made from 8 December 2026). Protected areas such as conservation areas exclude two-storey rear 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.
Design points for Hereford homes
The attached neighbour's light
A two-storey rear extension next to the party wall can take light from the neighbour's rear windows. Councils often use a 45-degree test, so the first floor may need to be shorter than the ground floor or set in from the shared boundary.
Rear, side or both
On a semi, a rear extension sits against the attached neighbour, while a side extension faces the detached neighbour and the street. We compare the space, cost and approval route for each, and for a wraparound, before you commit to one design.
How we'd run your project
Free site visit
We visit your home in Hereford, look at the structure, access and boundaries, and talk through what you want the new rooms to do.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.
Questions about two-storey extensions for semi-detached houses in Hereford
Do I need planning permission for a two-storey extension for a semi-detached house in Hereford?
Hereford is in England, so England planning rules apply. Depends on position: a two-storey rear extension may be permitted development (3 m deep, 7 m from the rear boundary); a two-storey side extension needs planning permission. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.
Who handles building regulations for a project in Hereford?
We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.
How much does a two-storey extension for a semi-detached house cost in Hereford?
Our guide for the West Midlands, which covers Hereford, is £2,000–£2,700 per m² including VAT. A typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £56,000–£75,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
Should I extend my semi to the side or the rear?
It depends on your plot and what you need. A rear extension keeps the side drive and can sometimes be permitted development, but it affects the attached neighbour. A side extension keeps the rear garden but always needs planning permission in England. We compare both at the free site visit.
Will a side extension make my semi look like a terrace?
It can if it fills the whole gap to the boundary at first floor and the neighbour does the same. Many councils ask for a first-floor gap to the side boundary or a set-back for this reason. We design the extension to keep the semi reading as one of a pair.
Nearby
Nearby towns we cover for two-storey extensions for semi-detached houses:
Other extensions in Hereford
- Rear
- Side
- Wraparound
- Part two-storey
- Over a garage
- First floor
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Hereford · Two-storey extensions for semi-detached houses across Herefordshire
Book a free site visit in Hereford and we'll tell you what's possible, what approvals you need and what the design stage would cost.