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.
Ayr sits within our coverage for a double-storey extension, as do neighbouring Irvine, Kilmarnock and Kilwinning. 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 Scotland is £58,000–£115,000 including VAT, and your written quote will spell out exactly what that covers.
- Guide price
- £58,000–£115,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- KA7, KA8 and KA9
- Planning rules
- Scotland
- Local area
- South Ayrshire
- Survey
- Free, with a written quote
How much does a double-storey extension cost in Ayr?
Budgeting for a double-storey extension in Ayr? The numbers below include VAT and are adjusted for Scotland, where costs are about 4% below the national guide. The headline range is £58,000–£115,000. Nothing is final until we have measured up at a free survey and agreed the specification with you.
| Type of job | What it usually involves | Guide in Ayr |
|---|---|---|
| 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 does the job include in Ayr?
- Groundworks, foundations and below-ground drainage
- Insulated cavity walls with brick or render to match the house
- First-floor joists, stud walls and new openings upstairs
- Scaffolding for the full build, erected and inspected
- 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.
In Ayr, as elsewhere in Ayrshire, we take the building's age and construction into account before recommending anything, because both can change what is involved in a double-storey extension.
Do you need permission in Ayr?
Homes in Ayr come under the regulations for Scotland, 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 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.
The four stages
A visit to your home
It starts with a survey at the property, free of charge. We check condition, access and services, ask how you want the finished result to look, and answer any questions you have about a double-storey extension.
Price and scope agreed
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Booking the work
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.
Finish and handover
During the work we protect the areas around it and tidy up at the end of each day. Once complete, we check the finish, remove our materials and hand over paperwork such as building control sign-off where it applies.
How we work
Double-storey extensions in Ayr: questions
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.
Is the price fixed?
Yes, for the specification we agree. Your written quote sets out exactly what is included at a fixed price. It only changes if you ask for something different, or if a problem the survey could not reasonably reveal later needs extra work. In either case we explain the change and confirm it in writing before going ahead.
How is the new roof joined to the existing house?
The new roof is usually tied into the existing roof so the two read as one. On a rear extension this often means a lower ridge or a hipped end, with valleys where the slopes meet. We strip back some existing tiles, fix new rafters and battens, and lay matching tiles or slates. Lead or proprietary flashings seal the junctions so water runs off properly.
Can the new upstairs room have its own bathroom?
A new upstairs room can usually have an en-suite, provided waste pipes can reach the soil stack or a new one can be installed. Running the waste pipe to the right falls is the main design question, and a pumped system is an option where gravity will not work. We plan bathroom positions at the design stage so pipes, ventilation and insulation are built in rather than added later.
How much will a double-storey extension cost in Ayr?
As a guide, expect to pay £58,000–£115,000 including VAT for a double-storey extension in Ayr. 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.
Also covering areas around Ayr
Whether you're in the centre of Ayr or on its outskirts, KA7, KA8 and KA9 addresses are covered. We extend the same service, and the same fixed-price approach, to Irvine, Kilmarnock and Kilwinning.

