A double-storey extension adds two floors of new space to your house in one build, typically a larger kitchen or living room downstairs with an extra bedroom, bathroom or en-suite above, sharing one set of foundations and one roof.
We offer a double-storey extension across Ayrshire, and Kilwinning is one of the places we cover, along with nearby Irvine, Kilmarnock and Ayr. 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 £58,000–£115,000 including VAT.
- Guide price
- £58,000–£115,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- KA13
- Planning rules
- Scotland
- Local area
- North Ayrshire
- Survey
- Free, with a written quote
How much does a double-storey extension cost in Kilwinning?
What should you budget for a double-storey extension in Kilwinning? Use the figures below as a starting point. Prices in Scotland sit about 4% below the national guide, so the range here is £58,000–£115,000 including VAT. Your fixed price comes in writing once we've surveyed the property, at no charge.
| Type of job | What it usually involves | Guide in Kilwinning |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £38,500–£62,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £58,000–£115,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £96,000–£173,000 |
Expect these to shape the final quote:
- How the new roof joins the existing roof
- Bathrooms, en-suites and plumbing on the upper floor
- Foundation depth, ground conditions and drains to divert
- Scaffolding duration, access and the level of finishes
What do you get?
- Insulated cavity walls with brick or render to match the house
- Roof structure tied into the existing roof, tiled to match
- Scaffolding for the full build, erected and inspected
- Electrics, plumbing and heating by qualified trades, with certificates
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
Local housing and a double-storey extension
Ayr, Kilmarnock and the coastal towns from Largs to Girvan have Victorian sandstone villas and terraces, with red sandstone common in older buildings. Former mining villages have rows of cottages, Irvine was developed as a new town from the 1960s, and harled post-war houses and newer estates are found across the area.
Sandstone homes need careful repointing and stone repairs, and harled houses commonly need re-rendering. Villas and semis suit extensions and loft conversions, and coastal homes often take window and roofline renewal.
For a double-storey extension in Kilwinning, this means checking things like wall construction, roof structure and existing services before we put a figure on paper.
Planning and building rules in Kilwinning
Because Kilwinning falls under Scotland's rules, the guidance below is the version relevant to you. Before sending a price, we check your property's position with the council.
In Scotland, extensions of more than one storey are only permitted development in narrow cases (Class 1B, well away from the boundary they face and outside conservation areas), so most need planning permission.
A building warrant is required before work starts. Scotland has no Party Wall Act; neighbour and title issues are handled 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
A visit to your home
A free survey comes first. It gives us what we need to price a double-storey extension properly, including dimensions, existing materials and access for deliveries, and gives you the chance to ask anything you like.
Price and scope agreed
We put everything into a written, fixed-price quote: the specification, what's excluded, staged payments and the expected time on site. Take whatever time you need to decide; there's no pressure to commit.
Dates and permissions
Before anyone starts, we confirm the programme in writing, check whether consents are required and arrange deliveries. If a skip or scaffolding on the road needs a permit, we apply for it.
Build and hand over
Our trades complete a double-storey extension while your point of contact keeps you updated. When everything is finished, we clear the site, take away waste and go through the result with you before handover.
What you can expect from us
Common questions
Which postcodes in Kilwinning do you cover?
We cover KA13, along with the rest of Ayrshire. 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.
Will the extension affect my neighbours?
A double-storey extension can affect neighbours' light, outlook and privacy, which is why planning departments look closely at height, depth and window positions. Side windows facing neighbours often need obscure glass. Work near a shared wall may also need party wall notices; the Party Wall etc. Act 1996 applies in England and Wales only. We talk through these points early so the design is realistic.
How long will a double-storey extension take?
On a typical home, allow 14–22 weeks on site. Larger projects, older buildings and extra work found once things are opened up can extend that, while simpler jobs may be shorter. Your quote includes an estimate of time on site, and your point of contact keeps you updated on the programme as the work progresses.
Is a double-storey extension better value than single-storey?
A double-storey extension usually gives better value per square metre than a single-storey one, because the same foundations and roof serve twice the floor area. The overall cost is higher, and planning can be harder because of the effect on neighbours. If you might want an extra bedroom later, building both floors now avoids a second round of disruption and scaffolding.
Can we live at home while it is built?
Most families stay at home during a double-storey extension. The new structure is built outside first, and we only break through into the existing rooms near the end, usually one floor at a time. Upstairs, this may mean a bedroom is out of use for a week or two. We fit dust screens, protect floors and stairs, and plan any time without water or power in advance.
Also covering areas around Kilwinning
Kilwinning and its KA13 postcodes are part of our coverage. Homeowners in Irvine, Kilmarnock and Ayr can also book a free survey with us and receive a written price for their job.