Two-storey extensions for detached houses in the Highlands, Moray and Islands

The Highlands, Moray and Islands at a glance

Nation: Scotland
Price region: Scotland
Postcode areas: AB, HS, IV, KW, PH, ZE
Towns covered: 21 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 on the mainland; island and remote addresses by arrangement, with travel costs agreed first

What a two-storey extension for a detached house involves

A two-storey extension for a detached house is a two-floor addition to the side, rear or both of a house that stands on its own plot. Detached houses often have room on more than one side, so there is more choice of layout and fewer shared-wall issues. The design still needs to respect boundaries, neighbours' windows and the look of the house.

The main places we list in the Highlands, Moray and Islands are Inverness (IV1), Elgin (IV30), Fort William (PH33), Nairn (IV12), Forres (IV36) and Buckie (AB56). We cover the villages in between too.

Guide price in Scotland

In Scotland, which includes Highlands, Moray and Islands, we'd expect a two-storey extension for a detached house to cost around £81,000–£108,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space), or £1,930–£2,580 per m² including VAT. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

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 detached house on a large plot may be able to use Class 1B permitted development if no part of the two-storey extension is within 10 m of any boundary, it is no higher than the house and is not in a conservation area. Otherwise a householder application costs £371. A building warrant is needed either way.

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

Choosing the best side

On a detached house you can often extend on either side or the rear. We look at orientation for daylight, where the stairs and landing are, the distance to each boundary, drains and trees, so the extension goes where it adds the most useful space.

Keeping it subordinate

Large detached houses can take a large extension, but councils still expect it to look secondary to the main house. A lower ridge, a modest set-back at the front and matching materials keep the proportions right, even on a wide plot.

How we work in the Highlands, Moray and Islands

Understand the brief
At your home in the Highlands, Moray and Islands 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.
Detail and price
Construction drawings, engineer's calculations and building warrant approval, then a written fixed price for the build.
Finish and certify
Second fix, plastering and making good, then the council's final building standards inspection and the completion paperwork.

Towns we cover in the Highlands, Moray and Islands

Two-storey extensions for detached houses in the Highlands, Moray and Islands: questions

How much does a two-storey extension for a detached house cost in the Highlands, Moray and Islands?

In Scotland our guide is £1,930–£2,580 per m² including VAT, so about £81,000–£108,500 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 extend a detached house on both sides?

Sometimes. With planning permission, a council may accept extensions on both sides if the house stays well proportioned and keeps gaps to the boundaries. It is more common to extend on one side and the rear, or with a wraparound. We look at the plot as a whole before suggesting more than one extension.

Is a detached house extension a better investment than moving?

It often costs less than the gap between your house and a larger one nearby, once property tax, legal fees and removal costs are counted, but that depends on your area. Extending also has limits: every street has a ceiling price. We give you build costs so you can compare them with local asking prices.

Will I need planning permission in the Highlands, Moray and Islands?

Highlands, Moray and Islands 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 the Highlands, Moray and Islands · About two-storey extensions for detached houses