Single-storey extensions in Cumbria

Covering Cumbria

Our coverage across Cumbria includes Carlisle, Barrow-in-Furness, Kendal and Whitehaven.

Projects in Cumbria are taken on by arrangement, and any travel and accommodation costs for the team are shown openly in the quote.

Homes in the North West

The North West has long rows of Victorian terraced houses in its towns and cities, alongside inter-war semis and post-war estates, so rear extensions, dormer lofts and kitchen extensions are common projects.

What is included in a single-storey extension in Cumbria?

A single-storey extension adds one level of new floor space to the back or side of a house, usually to open up a kitchen, dining or family room. It is the most common way to gain space without moving, and many can be built without a planning application.

Measured survey and design drawings
Planning or lawful development certificate where needed
Foundations, drainage and structural steel

What will a single-storey extension cost?

Typical ranges for single-storey extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

Single-storey extensions	Guide price incl. VAT
Standard specification	£2,600 to £3,000 per m²
Good specification	£3,000 to £3,500 per m²
High specification	£3,500 to £4,000 per m²

How is a single-storey extension approved in Cumbria?

Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.

In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary.

What can change the price or programme?

Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.
Kitchens and doors have long lead times, so we order them early.

How does the project run?

Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

What people ask before starting

Do I need planning permission for a single-storey extension?

Often not in England, if the extension stays within permitted development limits: 3 m deep on an attached house or 4 m on a detached house, and no higher than 4 m. Larger ones need prior approval or a planning application. Wales, Scotland and Northern Ireland have their own rules.

How long does a single-storey extension take to build?

The build itself usually takes 10 to 16 weeks once work starts on site. Design, approvals and ordering usually add 6 to 12 weeks before that.

Who deals with the council for a project in Cumbria?

We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.

Also covering

Learn more about single-storey extensions, or see every project we cover in Cumbria.