How Much Does a Home Extension Cost in Aberdeen?
As a rough rule, a home extension in the Aberdeen area works out at about £2,500 per square metre. A single-storey extension starts from around £45,000 and a double-storey from around £75,000. Here is what sits behind those figures, and what really moves the price.
An extension is usually the most cost-effective way to add proper living space to a home you already love, whether that is a wider kitchen-diner, a ground-floor bedroom and en suite, or a second-storey master suite. But "how much does an extension cost" is one of the hardest questions to answer honestly without seeing the house, because the same square metre of floor can cost very different amounts depending on your ground, your spec and your roofline.
This guide gives you the indicative figures we work to, then breaks down the things that push a quote up or down, so you arrive at your home extension survey already knowing roughly where your project sits. If you are weighing up going up versus going out, our comparison of a single versus double-storey extension is the natural companion read.
Extension cost at a glance
The table below sets out the indicative starting points we use for the Aberdeen and Aberdeenshire area. They are deliberately framed as "from" figures, because the right number for your home depends on the factors covered further down this page.
| Extension type | Typical use | Indicative from |
|---|---|---|
| Per square metre | The headline rate most schemes are built around | About £2,500 / m² |
| Single-storey extension | Kitchen-diner, lounge, ground-floor bedroom | £45,000 |
| Double-storey extension | Extra room above and below in one build | £75,000 |
| Kitchen extension | Open-plan kitchen with structural opening | Priced per project |
Why a double-storey costs less than two single-storeys
One figure in the table surprises people. A double-storey extension starts from around £75,000, which is well under twice the single-storey figure. That is because the most expensive parts of an extension, the groundworks, the foundations and the roof, are shared across both floors. Once you have dug and built the base and covered it over, adding a second storey on top is comparatively efficient. If you have the head height and the planning scope for it, going up as well as out is often the better value per square metre, which is exactly why so many Aberdeen homeowners ask us to price both options.
"The dearest parts of an extension are below the ground and above your head. A second storey shares both."
What drives the price up or down
Two extensions of the same floor area can land thousands apart. These are the factors that explain the gap, and the ones we look hardest at when we survey your home.
Size and footprint
Because the build is costed at roughly £2,500 per square metre, floor area is the single biggest lever. A modest rear addition and a wraparound that doubles your ground floor are very different projects. Shape matters too. A simple square footprint is more efficient to build than a long, narrow or angled one with more external wall per square metre of floor gained.
Ground conditions
What is under your garden is the great unknown until we dig. Aberdeen and Aberdeenshire sit on a lot of granite, and rock close to the surface, a high water table, made-up ground or nearby trees can all mean deeper or specially engineered foundations. Good ground keeps you near the indicative figure. Difficult ground is the most common reason a quote comes in higher.
Specification and finish
The structure is only part of the spend. The level of finish you choose for floors, joinery, tiling, lighting and heating can move the total significantly. A straightforward, well-built room finished to a sensible standard sits at the lower end. A high-specification space with underfloor heating, premium flooring and bespoke joinery sits higher.
Glazing
Glass is one of the easiest ways to lift both the feel and the cost of an extension. Bi-fold or sliding doors, large picture windows, roof lanterns and rooflights all add light and all add money compared with standard windows. Many of our nicest projects spend a meaningful share of the budget here, and it is usually money well spent, but it is worth deciding early.
Structural openings
An extension only feels like part of the house once it connects to it, and that usually means knocking through a load-bearing wall. Forming a wide opening between the old and new space needs steel beams sized by a structural engineer, and the bigger and more open the link, the more steel and support work involved. This is a common feature of kitchen extensions and a real cost driver.
The building warrant
In Scotland a habitable extension needs a building warrant from Aberdeen City Council or Aberdeenshire Council, and many projects also need planning permission, which is a separate consent. There are drawings, structural calculations, fees and an inspection process behind both. We handle that liaison for you, and you can read more on when consent is required in our guide to extension planning permission in Aberdeen.
What the price includes
When we quote a turnkey extension, the figure is designed to cover the building work from the ground up to a finished, usable room. As standard that means:
- Groundworks and foundations sized for your ground conditions.
- The structure, including walls, steel beams for any openings, and the roof.
- Insulation to current building warrant standards for a warm, efficient room.
- Windows and doors, including the glazing specified for your design.
- Internal finishing, including plastering, electrics, plumbing, decoration and flooring to the agreed specification.
- Building warrant liaison, so the drawings, applications and inspections are handled for you.
What sits outside the build cost
To keep our quotes honest, some items are usually priced separately or supplied by you, rather than buried in a headline figure. These typically include:
- Kitchen units, worktops and cabinetry, which vary enormously by choice and supplier.
- Appliances, such as ovens, hobs, fridges and extraction.
- Specialist finishes, for example bespoke joinery, feature stonework, high-end tiling or smart-home systems.
For a kitchen extension in particular, this is why we price per project. If a new kitchen is the heart of your plans, our kitchen cost guide sets out what the units, supply and fit elements add on top of the building work, and our kitchens service page shows the kind of spaces we create.
- Check whether the figure is the building work only or a turnkey price including finishes.
- Confirm whether kitchen units and appliances are inside or outside the number.
- Ask how foundations are priced and what happens if the ground proves difficult.
- Make sure the building warrant and any planning fees are accounted for.
- Remember every figure here is indicative and excludes VAT until a survey confirms it.
How to budget with confidence
The most reliable way to set a budget is to start from your floor area at about £2,500 per square metre, then adjust for the drivers above. A 20 square metre single-storey room on good ground with a standard finish will sit near the £45,000 starting point. Add a wall of bi-fold doors, a roof lantern, difficult foundations and a high-specification finish, and the same footprint costs more. A double-storey on the same base starts from around £75,000 because you gain a second floor for a modest premium.
Whatever your starting point, a free site survey and written quote turns these indicative figures into a firm, itemised number with no surprises. We are a family-run firm with over 20 years' experience, FMB members and TrustMark registered, fully insured, and we put everything in writing before any work begins. Choosing the right builder matters as much as the price, and our guide on how to choose a builder in Aberdeen explains what to look for.
Want a firm price for your extension?
Book a free survey and we will measure up, talk through your options and put an honest, itemised quote in writing. No ballpark guesses and no pressure to go ahead. Call us on 07946 046935.
As a working rule, a home extension in the Aberdeen area costs about £2,500 per square metre. That covers the building work to a finished room, but the final rate depends on your ground conditions, the level of finish, the glazing and any structural openings. This is indicative only, subject to a site survey, and excludes VAT.
A single-storey extension typically starts from around £45,000. The exact figure depends on the floor area, the foundations your ground needs, the windows and doors you choose and the finish. A free survey and written quote will give you a firm, itemised number. Indicative only, subject to a site survey, and excludes VAT.
A double-storey extension starts from around £75,000, which is less than twice the single-storey figure because the foundations and roof are shared across both floors. Once the base and roof are built, adding the second storey is comparatively efficient, so going up as well as out is often better value per square metre. Indicative only, subject to a site survey, and excludes VAT.
Our turnkey quotes cover the groundworks and foundations, the structure and roof, insulation, windows and doors, internal finishing such as plastering, electrics, plumbing and flooring, and the building warrant liaison. Kitchen units, appliances and specialist finishes are usually priced separately so you can see exactly what you are paying for.
Yes. A habitable extension needs a building warrant from Aberdeen City Council or Aberdeenshire Council, and many projects also need planning permission, which is a separate consent. We handle the drawings, applications and inspections for both as part of the service, so you do not have to navigate the process yourself.
A kitchen extension combines building work with kitchen units, worktops, appliances and finishes that vary widely from one home to the next, so we price it per project rather than quoting a single figure. We give you a clear, itemised written quote after a survey so you can see the building work and the kitchen elements separately.