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 take on a double-storey extension throughout Greenock and the surrounding PA14, PA15, PA16 and PA19 postcodes, as well as in Helensburgh, Dunoon and Vale of Leven. The guide range for this work in Scotland is £58,000–£115,000 including VAT; where your project falls depends on its size, the materials you pick and how easy the site is to reach. A free survey turns that range into a fixed figure.
- Guide price
- £58,000–£115,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- PA14, PA15, PA16 and PA19
- Planning rules
- Scotland
- Local area
- Inverclyde
- Survey
- Free, with a written quote
How much does a double-storey extension cost in Greenock?
In Greenock, guide figures for a double-storey extension sit at £58,000–£115,000, VAT included. We set them using rates for Scotland, currently about 4% 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 Greenock |
|---|---|---|
| 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 |
The main things that change the figure:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Bathrooms, en-suites and plumbing on the upper floor
- Scaffolding duration, access and the level of finishes
What does the job include in Greenock?
- Groundworks, foundations and below-ground drainage
- 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
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
Local housing and a double-storey extension
Paisley has sandstone tenements and terraces from its textile era, Greenock and Port Glasgow have tenements and housing climbing the hills above the Clyde, and Gourock and Kilmacolm have Victorian villas. Post-war estates and newer private housing surround the towns, and roughcast is a common finish.
Inverclyde is one of the wettest parts of lowland Scotland, and homes facing the Firth of Clyde take wind and driving rain.
None of this holds for every street in Greenock, which is why we look at your actual house before pricing a double-storey extension rather than assuming from its age alone.
Permissions for a double-storey extension in Greenock
Each UK nation sets its own consent rules, and Greenock is in Scotland. What follows is a plain summary; we check the specifics for your property with the council before pricing anything.
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.
What happens after you get in touch?
A visit to your home
First, someone visits your home in Greenock to see the space, take measurements and note anything that could affect the work, such as access or the condition of what is there. There is no charge for this visit.
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
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a double-storey extension are in place before the first day on site.
Finish and handover
Work goes ahead as scheduled and you deal with one contact throughout. When the last trade leaves, we clear and clean the site, talk you through what has been done and pass on any certificates and care instructions.
What you can expect from us
Frequently asked questions
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.
Do I need planning permission for a two-storey extension?
Most two-storey extensions need planning permission, but it depends on the size, height and position, your home's location, whether it is listed or in a conservation area, and which UK nation you are in. In England, a two-storey rear extension can sometimes be built under permitted development if it is no deeper than 3m and at least 7m from the rear boundary. We check what applies before quoting.
Which postcodes in Greenock do you cover?
We cover PA14, PA15, PA16 and PA19, along with the rest of Renfrewshire and Inverclyde. 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.
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.
Do I need planning permission in Greenock?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Greenock is in Scotland, so Scotland'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.
Nearby towns
Greenock and its PA14, PA15, PA16 and PA19 postcodes are part of our coverage. Homeowners in Helensburgh, Dunoon and Vale of Leven can also book a free survey with us and receive a written price for their job.