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.
We offer a single-storey extension across Edinburgh and the Lothians, and Bonnyrigg is one of the places we cover, along with nearby Musselburgh, Penicuik and Edinburgh. Before anything is agreed we visit, check the existing structure and talk through your options. You then receive a written quote setting out the full scope; for most homes in Scotland it sits within £33,500–£72,000 including VAT.
- Guide price
- £33,500–£72,000 inc VAT
- Time on site
- 10–16 weeks on site
- Postcodes
- EH18, EH19, EH20, EH22 and EH24
- Planning rules
- Scotland
- Local area
- Midlothian
- Survey
- Free, with a written quote
What should you budget for a single-storey extension in Bonnyrigg?
Every figure below is a guide for a single-storey extension in Bonnyrigg, inclusive of VAT. Regional pricing for Scotland works out about 4% below the national guide, and the overall span is £33,500–£72,000. The survey costs you nothing, and after it we commit to a firm price for your specification in writing.
| Type of job | What it usually involves | Guide in Bonnyrigg |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £21,000–£38,500 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £33,500–£72,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £67,000–£125,000 |
Expect these to shape the final quote:
- 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
Scope of the work
- Groundworks, foundations and below-ground drainage
- Cavity walls built and insulated to building regulations
- Steel beams to open into the existing house
- Electrics and plumbing by qualified trades, with certificates
- Windows and external doors, including bifolds if chosen
- Building control inspections and completion certificate
Local housing and a single-storey extension
Edinburgh's New Town is a planned Georgian sandstone townscape within a World Heritage Site, and districts such as Marchmont and Leith have Victorian tenements. Bungalows and villas fill the suburbs, Midlothian has former mining villages, Livingston was built as a new town, and East Lothian villages often have red pantile roofs.
Listed and conservation-area homes need careful window and stone repairs. Bungalows commonly suit loft conversions and dormers, and suburban semis take extensions and garage conversions.
For a single-storey extension in Bonnyrigg, this means checking things like wall construction, roof structure and existing services before we put a figure on paper.
Planning and building rules in Bonnyrigg
Bonnyrigg is in Scotland, so the planning and building rules set out below are the ones that apply. We confirm the details with the council before we quote.
In Scotland, Class 1A permitted development covers some single-storey extensions, within limits on depth, height and distance from boundaries, and not in conservation areas or on flats. Anything outside those limits needs planning permission from the council.
A building warrant from the council’s building standards service is usually needed before work starts, and a completion certificate is accepted at the end. There is no Party Wall Act in Scotland; work near a boundary is agreed with neighbours under general law.
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
Free site survey
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.
Price and scope agreed
The quote arrives in writing, not over the phone. It covers the full scope, the finishes you've chosen, any exclusions and the payment schedule, with a fixed price tied to that specification.
Dates and permissions
We handle the paperwork side: checking whether planning permission or building control approval is needed, submitting applications where they are, and scheduling the trades and materials around your dates.
Build and hand over
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
What you can expect from us
Frequently asked questions
Do I need an architect for an extension?
You need proper drawings for an extension, but not always a full architect service. A designer or architectural technician can produce planning and building regulations drawings, and a structural engineer provides beam and foundation calculations. If you already have drawings, we price from them. If not, we can arrange the drawings and calculations as part of the project so everything is coordinated from the start.
Do I need planning permission for a single-storey extension?
Whether you need planning permission depends on the extension's size and height, how close it is to boundaries, your home's location, whether it is listed or in a conservation area, and which UK nation you live in. In England, many rear extensions up to 3m deep on a semi or terrace, or 4m on a detached house, can be built under permitted development. We check the rules that apply to your home before quoting.
How much will a single-storey extension cost in Bonnyrigg?
As a guide, expect to pay £33,500–£72,000 including VAT for a single-storey extension in Bonnyrigg. That range is adjusted for Scotland, which runs about 4% 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.
Is a flat roof or a pitched roof better on an extension?
A flat roof is quicker to build and usually costs less, gives a clean modern look and works well with a roof lantern. A pitched roof matches the main house, sheds water faster and allows a vaulted ceiling, but it costs more and its height can affect neighbours. Modern flat roofs in EPDM rubber or GRP last well when properly detailed. Planning rules on height can also decide the choice.
Which postcodes in Bonnyrigg do you cover?
We cover EH18, EH19, EH20 and EH22, along with the rest of Edinburgh and the Lothians. 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.
Near Bonnyrigg
From EH18, EH19, EH20 and EH22 to the edges of Bonnyrigg and on into Musselburgh, Penicuik and Edinburgh, we can arrange a site visit and a written quote for your project, planned around dates that work for you.