Two-storey annexe extensions in Edinburgh and the Lothians

Edinburgh and the Lothians at a glance

Nation: Scotland
Price region: Scotland
Postcode areas: EH
Towns covered: 24 listed below, plus surrounding villages
Approval route: Planning permission is usually needed: Class 1B permitted development only applies if every part of the extension is at least 10 m from all boundaries. A building warrant is needed before work starts.
Site visits: Free, no obligation

What a two-storey annexe extension involves

A two-storey annexe extension is an attached extension laid out as self-contained living space on two floors, usually with a living area and kitchenette below and a bedroom and shower room above, for a relative living with the family. It stays part of the main house rather than a separate home. Planning and council tax rules treat it differently from a separate dwelling.

The main places we list in Edinburgh and the Lothians are Edinburgh (EH1), Livingston (EH53), Musselburgh (EH15), Bathgate (EH48), Bonnyrigg (EH18) and Penicuik (EH26). We cover the villages in between too.

Guide price in Scotland

Using our Scotland rates, a two-storey annexe extension with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £81,000–£108,500 (plus kitchenette and shower room fittings, priced to your choice), including VAT. Bigger or more glazed designs cost more per m². These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

Spec	Per m²	Typical project
Essential	£1,770–£2,380 per m²	£74,500–£100,000
Standard	£1,930–£2,580 per m²	£81,000–£108,500
Premium	£2,310–£3,100 per m²	£97,000–£130,500

Rules in Scotland

In Scotland, a two-storey annexe extension needs to be at least 10 m from every boundary to be permitted development under Class 1B, so most need a householder application (£371, decided within two months). The building warrant covers fire safety and escape for the self-contained layout.

Approval in Scotland: Householder planning application: £371. Councils have two months to decide a local planning application.

Building standards: A building warrant from the council's building standards service before work starts, and a completion certificate at the end. Scotland uses its own Technical Handbooks.

There is no Party Wall Act in Scotland. Shared walls and boundaries are governed by title deeds and common law, so we speak to neighbours early and record the condition of shared structures.

Getting the design right

Ground-floor living for the future

Many annexes are planned so the occupant could live on the ground floor if stairs become difficult. A ground-floor bedroom space, a level-access shower and wider doorways cost little at the design stage and are expensive to add later.

Fire separation and escape

A kitchenette in an annexe and a bedroom above need safe escape and suitable separation from the main house. Building standards checks the escape windows, smoke alarms and the door between the two parts.

How we work in Edinburgh and the Lothians

Understand the brief
At your home in Edinburgh and the Lothians we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Design and approvals
We draw the extension and check it against the rules for Scotland, then apply for planning permission or a certificate of lawfulness, whichever fits.
Engineer it
Foundations sized for two floors, steels for any openings, and a building warrant, all before anyone starts on site.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.

Towns we cover in Edinburgh and the Lothians

Two-storey annexe extensions in Edinburgh and the Lothians: questions

How much does a two-storey annexe extension cost in Edinburgh and the Lothians?

In Scotland our guide is £1,930–£2,580 per m² including VAT, so about £81,000–£108,500 (plus kitchenette and shower room fittings, priced to your choice) for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Essential and Premium specs move that by roughly 8% down or 20% up.

Can I rent out an annexe later?

Not always. Many annexe permissions include a condition that it is only used by members of the household, so renting it out may need a fresh planning application. If you think you might want to let it, tell us at the start so we can explain the options.

Can an annexe have its own front door?

It can, but a separate front door, kitchen and address together make it look more like a separate home, which can change how the council treats it for planning. Many annexes have their own door to the garden or side and an internal door to the main house. We explain how each choice is likely to be viewed before the design is fixed.

Can an annexe be designed for someone with limited mobility?

Yes. We can plan a ground-floor bedroom space, a level-access shower, wider doorways, lever handles and space for a stairlift later. These features are much cheaper to build in at the start than to add afterwards, and they keep the annexe useful as needs change.

Will I need planning permission in Edinburgh and the Lothians?

Edinburgh and the Lothians is in Scotland. Planning permission is usually needed: Class 1B permitted development only applies if every part of the extension is at least 10 m from all boundaries. A building warrant is needed before work starts.

Neighbouring areas

All extension services in Edinburgh and the Lothians · About two-storey annexe extensions