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.
Homes across Dyfed vary a great deal, so we price a single-storey extension only after seeing the property. Our coverage takes in Llanelli, Ammanford, Aberystwyth and Carmarthen and the surrounding districts. As a guide, expect £32,000–£69,000 including VAT in Wales; the final figure depends on size, materials and access. Any permissions are checked against the rules for Wales before we quote.
- Guide price
- £32,000–£69,000 inc VAT
- Time on site
- 10–16 weeks on site
- Planning rules
- Wales
- Price level
- About 8% below the national guide
- Towns listed
- 4
- Survey
- Free, with a written quote
How much does a single-storey extension cost in Dyfed?
To help you plan, we show what a single-storey extension typically costs in Dyfed instead of holding figures back for a sales call. The range is £32,000–£69,000 with VAT, using rates in Wales that are about 8% below the national guide. A free survey then fixes your actual price.
| Type of job | What it usually involves | Guide in Dyfed |
|---|---|---|
| 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 |
What moves the price up or down:
- Floor area, shape and number of corners
- 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
What’s included?
- Groundworks, foundations and below-ground drainage
- Cavity walls built and insulated to building regulations
- Flat or pitched roof, with rooflights or a lantern if specified
- Electrics and plumbing by qualified trades, with certificates
- Plastering, screed floor and internal doors
- Building control inspections and completion certificate
Housing across Dyfed
Dyfed covers Carmarthenshire, Ceredigion and Pembrokeshire. Stone cottages and farmhouses under slate roofs are common, often rendered or colour-washed, as in Tenby's brightly painted terraces. Llanelli has Victorian industrial terraces, Aberystwyth and Carmarthen have Georgian and Victorian centres, and bungalows and newer estates surround most towns.
Stone homes often need lime render, repointing and roof slating repairs. Terraces suit loft conversions and extensions, and rural bungalows commonly take extensions, porches and driveways.
Atlantic weather brings strong winds, driving rain and salt to the coast, so exposure ratings matter when specifying render and pointing.
Planning and building rules in Dyfed
Which rules apply depends on where you live. For Dyfed, the answer is Wales, and the points below reflect that; we verify them with the council before quoting.
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.
How does the job run?
Free site survey
A free survey comes first. It gives us what we need to price a single-storey extension properly, including dimensions, existing materials and access for deliveries, and gives you the chance to ask anything you like.
Written quote
Next you receive a written quote with a fixed price for the agreed specification. It lists what is included, what is not, and how payments are staged, so you can compare it properly.
Getting ready
Once you accept, we agree start dates, order materials and deal with any planning, building control or neighbour notices the job needs. You'll know who is coming and when before work begins.
Build and hand over
The work is carried out to the agreed specification, with floors and furniture protected and the site kept tidy. At the end we clean up, walk through the finished job with you and hand over any certificates.
How we work
Questions about a single-storey extension in Dyfed
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.
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.
How much will a single-storey extension cost in Dyfed?
As a guide, expect to pay £32,000–£69,000 including VAT for a single-storey extension in Dyfed. That range is adjusted for Wales, which runs about 8% below the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
Can we stay at home during the build?
Most people stay at home while we build a single-storey extension, because the new structure goes up outside before we break through. The disruptive part is usually the last few weeks, when we open into the house and fit the kitchen. We put up dust screens, keep a safe route through the house and agree a temporary kitchen setup if needed. Water and power are only off for short, planned periods.
Which postcodes in Dyfed do you cover?
We cover SA15, SA18, SY23 and SA31, along with the rest of Dyfed. If your postcode is not listed, get in touch anyway: our coverage is UK-wide, and we can usually arrange a survey wherever you live. Enter your postcode in the guide-price tool or contact form and we will confirm.
Towns in Dyfed
Choose your town from the list to see how we price and plan a single-storey extension in your part of Dyfed, including typical time on site.