A single-storey extension is a new ground-floor room built onto your house, usually at the rear or side, with its own foundations, walls and roof, creating a bigger kitchen, living space or bedroom without moving home.
Holyhead sits within our coverage for a single-storey extension, as do neighbouring Caernarfon, Bangor, Gwynedd and Llandudno. Before giving a price we want to see the property: the condition of what's there now, the access, and anything that might need extra work. The guide range for Wales is £32,000–£69,000 including VAT, and your written quote will spell out exactly what that covers.
- Guide price
- £32,000–£69,000 inc VAT
- Time on site
- 10–16 weeks on site
- Postcodes
- LL65
- Planning rules
- Wales
- Local area
- Isle of Anglesey
- Survey
- Free, with a written quote
How much does a single-storey extension cost in Holyhead?
In Holyhead, guide figures for a single-storey extension sit at £32,000–£69,000, VAT included. We set them using rates for Wales, currently about 8% below the national guide. The table shows what pushes a project towards either end of the range; your own price is set after a free survey.
| Type of job | What it usually involves | Guide in Holyhead |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £20,000–£37,000 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £32,000–£69,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £64,000–£120,000 |
Your price depends mostly on:
- Roof type, rooflights, lanterns and the amount of glazing
- Ground conditions, foundation depth and drains to divert
- Steelwork needed to open into the existing house
- Finishes, kitchen, flooring and heating specification
What’s included?
- Groundworks, foundations and below-ground drainage
- Flat or pitched roof, with rooflights or a lantern if specified
- Electrics and plumbing by qualified trades, with certificates
- Windows and external doors, including bifolds if chosen
- Plastering, screed floor and internal doors
- Building control inspections and completion certificate
Building in Holyhead
Slate defines much of Gwynedd, from quarrying villages such as Bethesda and Blaenau Ffestiniog with their stone terraces to slate roofs across the county. Bangor and Caernarfon have Victorian and Georgian streets, Anglesey has stone cottages and bungalows, and resorts such as Pwllheli and Barmouth have Victorian terraces and newer bungalows.
Eryri (Snowdonia) is among the wettest areas in the UK, and exposed coasts take strong wind and salt, so render and roof details need to be robust.
So when we survey a Holyhead property for a single-storey extension, the first step is working out how it was built and what has been changed since.
Permissions for a single-storey extension in Holyhead
Homes in Holyhead come under the regulations for Wales, summarised below. We don't rely on general rules alone: we confirm the position for your address with the council before a quote goes out.
In Wales, permitted development allows many single-storey rear extensions, with depth and height limits that depend on the type of house and how close the extension comes to your boundaries. Side extensions, listed buildings, conservation areas and flats usually need planning permission.
Building Regulations in Wales apply to extensions, from foundations to insulation and fire safety. The Party Wall etc. Act 1996 applies in Wales as it does in England.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
From survey to handover
We look at the job
We arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a single-storey extension so the price reflects your home.
Quote in writing
After the survey we send a quote for a single-storey extension that fixes the price for the scope we've agreed. If you want to change materials or scope, we revise it in writing before anything is booked.
Getting ready
Preparation matters as much as the build. We agree access, parking and working hours with you, order materials in good time, and confirm any permissions so the job isn't held up once it starts.
Finish and handover
The job proceeds in the order set out in the programme, with dust and debris kept under control. Finally we tidy away, inspect the work together and pass the finished project over to you with its paperwork.
Why homeowners choose us
Questions about a single-storey extension in Holyhead
How much does a single-storey extension cost?
A typical single-storey rear extension of 15–25m² costs £32,000–£69,000, built to a plastered finish ready for your kitchen and decoration. As a guide, allow roughly £1,600–£2,800 per square metre plus fixed costs for groundworks, steelwork and fees. Smaller extensions cost more per square metre. The kitchen, flooring and large glazed doors are usually the biggest extras. We confirm a fixed price for the agreed specification after the survey.
Do I need planning permission in Holyhead?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Holyhead is in Wales, so Wales's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
How long does a single-storey extension take to build?
A single-storey extension usually takes 10–16 weeks on site, from digging foundations to final plastering. Bad weather, deep foundations or a complex roof can add time. Before work starts, allow several weeks for drawings, structural calculations and building control approval, and longer if planning permission is needed. We give you a stage-by-stage programme with your quote so you know what happens each week.
Do you cover Caernarfon, Bangor, Gwynedd and Llandudno?
Yes. As well as Holyhead, we cover Caernarfon, Bangor, Gwynedd and Llandudno and the rest of Gwynedd. Our coverage is UK-wide, so the process is the same wherever you are: a free site survey, a quote in writing that fixes the price for the agreed scope, and one point of contact while the work is planned and carried out.
What is the Party Wall Act and does it apply to me?
The Party Wall etc. Act 1996 applies in England and Wales only. In England and Wales, it requires you to give notice to neighbours before certain work on or near a shared wall, such as digging foundations within 3m of their building and deeper than its footings. Neighbours can agree or appoint a surveyor. Scotland and Northern Ireland have no equivalent Act, though general rights still apply. We identify whether notices are needed during the survey.
Nearby towns
We survey and quote throughout Holyhead's LL65 postcodes and in surrounding places such as Caernarfon, Bangor, Gwynedd and Llandudno. The process and pricing approach are identical in each of them.