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 Gwynedd?
In Gwynedd, 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. Building costs in Wales run about 8% below the UK average, and the figures for Gwynedd are adjusted to reflect that. 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:
- Access for materials on terraced streets
- Party wall surveyor fees for one or both neighbours
- Kitchen and flooring specification
- Drainage changes
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a wraparound extension in Gwynedd?
Approvals for a wraparound extension in Gwynedd follow the rules for 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.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
What we take care of:
- Design and planning application
- Party wall notices and surveyor liaison
- Building control completion
- Removal of internal and external walls
- Foundations and drainage
- Structural engineer’s design for steels and supports
How long does it take?
The build itself usually takes 12 to 18 weeks on site. Before that, surveys, drawings and approvals usually take 3 to 4 months, longer if the council asks for changes.
Building in Gwynedd
Terraced houses in Welsh towns often have narrow plots, which suits rear and side return extensions and rear dormers.
Towns we cover in Gwynedd include Bangor, Llandudno, Holyhead and Caernarfon.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about wraparound extensions in Gwynedd
Is a wraparound worth it?
It gives the biggest ground-floor space without going upwards. Whether it adds value depends on your street and house, so we suggest checking local sale prices before committing.
How much does a wraparound extension cost in Gwynedd?
In Gwynedd, 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 a wraparound extension take in Gwynedd?
Typically 12 to 18 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
Do I need planning permission for a wraparound extension in Gwynedd?
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.
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
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.