First-floor extensions in Egremont

Quick reference for homeowners in Egremont.

Postcode districts: CA19, CA20, CA21, CA22 and CA27
County / area: Cumbria, England
Price region: North West England
Guide price: £24,000–£34,500 (£1,710–£2,470 per m²)
Approval route: It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission.
Nearest towns: Cleator Moor (2.9 miles), Whitehaven (5.3 miles), Workington (11.3 miles)
Distance to Carlisle: about 37.1 miles
First visit: Free, no obligation

About a first-floor extension

A first-floor extension is a new upstairs room built on top of an existing single-storey part of your house, such as a rear kitchen extension, a utility or a side annexe. It adds a bedroom, bathroom or study without enlarging the footprint. Whether it works depends mainly on whether the walls and foundations below can carry the extra load.

We cover Egremont (CA19, CA20, CA21, CA22 and CA27) and the places around it, including Cleator Moor (2.9 miles), Whitehaven (5.3 miles) and Workington.

What it costs in Egremont

In North West England, which includes Egremont, we'd expect a first-floor extension to cost around £24,000–£34,500 for 4 m × 3.5 m of new first-floor space (14 m²), or £1,710–£2,470 per m² including VAT. Professional fees for drawings and the structural engineer are listed separately on our prices page.

Spec	Per m²	4 m × 3.5 m of new first-floor space (14 m²)
Essential	£1,570–£2,270 per m²	£22,000–£32,000
Standard	£1,710–£2,470 per m²	£24,000–£34,500
Premium	£2,050–£2,960 per m²	£28,500–£41,500

Planning and building regulations in Egremont

In England, adding a first floor turns a single-storey extension into one of more than one storey. To be permitted development, the extension as a whole must go no more than 3 m beyond the rear wall of the original house and stay at least 7 m from the rear boundary, with matching materials and roof pitch. Over a side extension it always needs planning permission, costing £548 (or £575 for applications made from 8 December 2026).

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Egremont homes

Tying into the house

The new floor and walls must line up with the existing first floor, often through a new opening in the rear wall above the old one. Floor levels, the position of upstairs windows and the existing roof all affect where the opening can go, so we survey both floors carefully.

Escape and fire safety

A new first-floor bedroom needs an escape window with a clear opening of at least 0.33 m², at least 450 mm wide and 450 mm high, with the bottom no more than 1,100 mm above the floor, unless there is a protected route to the stairs.

How we'd run your project

Visit and first ideas
One of our team visits your house in Egremont, checks the walls, roof and drains, and sketches out options with you.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about first-floor extensions in Egremont

Do I need planning permission for a first-floor extension in Egremont?

Egremont is in England, so England planning rules apply. It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Which postcodes do you cover around Egremont?

We cover Egremont (CA19, CA20, CA21, CA22 and CA27) and nearby places including Cleator Moor, Whitehaven and Workington, plus the rest of Cumbria. The first site visit is free.

Who handles building regulations for a project in Egremont?

We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

What happens to the room below while the first floor is built?

The old roof is removed, so the room below is exposed for a short period. We fit temporary weather protection, plan the work so the roof comes off only when the new structure is ready, and agree with you which rooms will be out of use and for roughly how long.

Will the first-floor extension match my house?

It should, and in England matching materials and roof pitch is a condition of permitted development. We match brick, tile, mortar colour and window style where we can, and tell you at the design stage if an exact brick match is not available, so you can choose between the closest match and render or cladding.

Nearby

Other towns near Egremont:

Other extensions in Egremont

All two-storey extension services in Egremont · First-floor extensions across Cumbria

Want a figure first? Try our guide price tool, then book a free visit to firm it up.