What is a wraparound extension?

A wraparound extension combines a side return and a rear extension into one L-shaped addition. It gives the largest possible ground floor, often creating an open-plan kitchen, dining and living space across the whole width of the house.
How much does a wraparound extension cost in Milford Haven?
In Milford Haven, a wraparound extension typically costs £2,000–£2,950 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £56,000–£82,500. That range is adjusted for Wales, where domestic building work typically costs around 8% below the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £40,000–£59,000 |
| Typical project (28 m²) | £56,000–£82,500 |
| Larger project (39 m²) | £78,000–£115,000 |
| Rate per m² | £2,000–£2,950 |
Your quote will depend mainly on:
- Drainage changes
- Access for materials on terraced streets
- Steelwork and propping of the existing house
- Party wall surveyor fees for one or both neighbours
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a wraparound extension in Milford Haven?
Before anything is built in Milford Haven, we confirm which approvals apply in Wales. In Wales a wraparound extension combines side and rear elements; it can only be permitted development if each part meets the limits, so many need a householder planning application.
Building regulations in Wales are set by the Welsh Government. Approval comes from the council’s building control service or a registered building control approver, with inspections during the work and a completion certificate at the end.
We check this for your address before design work starts, so there are no surprises later.
What we handle
The work we manage on a wraparound extension:
- Underfloor heating option, electrics and plastering
- Design and planning application
- Foundations and drainage
- Building control completion
- Removal of internal and external walls
- Party wall notices and surveyor liaison
How long does it take?
The build itself usually takes 12 to 18 weeks on site. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Milford Haven
Wales has many terraced valley streets, stone cottages and post-war estates, so extension designs are shaped by slopes, materials and local character.
Milford Haven sits in Dyfed, about 33 miles west of Carmarthen. We cover the whole of Milford Haven, including postcodes SA73.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about wraparound extensions in Milford Haven
Do I need planning permission for a wraparound extension in Milford Haven?
In Wales a wraparound extension combines side and rear elements; it can only be permitted development if each part meets the limits, so many need a householder planning application.
What about the old back addition?
The side wall of the back addition is usually removed and replaced with a steel beam, so the old kitchen joins the new space.
Do you build wraparound extensions in Milford Haven?
Yes. We build wraparound extensions across Milford Haven, including postcodes SA73. Every project starts with a free home visit.
How much does a wraparound extension cost in Milford Haven?
In Milford Haven, a wraparound extension typically costs £2,000–£2,950 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £56,000–£82,500. Your fixed price depends on the survey and drawings.
How long does it take to build?
Around 12 to 18 weeks on site after approvals. Design, planning and party wall matters usually take 3 to 4 months beforehand.
Will both neighbours be affected?
Usually only the neighbour on the side return side, but rear foundations near either boundary can trigger party wall notices.
