First-floor extensions in Matlock

Before you start in Matlock, here's what applies.

Postcode districts: DE4 and DE45
County / area: Derbyshire, England
Price region: East Midlands
Guide price: £24,500–£35,500 (£1,760–£2,550 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: Alfreton (7.7 miles), Belper (8.5 miles), Chesterfield (9.6 miles)
Distance to Derby: about 15.3 miles
First visit: Free, no obligation

About a first-floor extension

A first-floor extension suits you if your house already has a single-storey extension and you need more space upstairs. You get a structural check of the existing walls and foundations, a design that ties the new floor into the house, the approvals your nation needs, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.

Around Matlock we also work in Alfreton, Belper and Chesterfield, and across the rest of Derbyshire. Postcode districts in and near Matlock: DE4 and DE45.

What it costs in Matlock

Most of the cost of a first-floor extension is set by its size and specification. For Matlock and the rest of the East Midlands, our guide is £1,760–£2,550 per m² including VAT, so about £24,500–£35,500 for 4 m × 3.5 m of new first-floor space (14 m²). Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.

Spec	Per m²	4 m × 3.5 m of new first-floor space (14 m²)
Essential	£1,620–£2,340 per m²	£22,500–£33,000
Standard	£1,760–£2,550 per m²	£24,500–£35,500
Premium	£2,120–£3,060 per m²	£29,500–£43,000

Planning and building regulations in Matlock

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 Matlock 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.

Replacing the flat roof

The existing roof usually comes off and is replaced by a new first-floor structure. The room below is exposed for a short time, so we plan temporary weatherproofing and sequence the work to keep the kitchen or living room usable for as long as possible.

How we'd run your project

Start at your house
We come to your home in Matlock, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Matlock.
Engineer it
Foundations sized for two floors, steels for any openings, and building control approval, 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.

Questions about first-floor extensions in Matlock

How much does a first-floor extension cost in Matlock?

Our guide for the East Midlands, which covers Matlock, is £1,760–£2,550 per m² including VAT. A typical project with 4 m × 3.5 m of new first-floor space (14 m²) comes to about £24,500–£35,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Who handles building regulations for a project in Matlock?

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.

Which postcodes do you cover around Matlock?

We cover Matlock (DE4 and DE45) and nearby places including Alfreton, Belper and Chesterfield, plus the rest of Derbyshire. The first site visit is free.

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.

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.

Nearby

The same service in neighbouring towns:

Other extensions in Matlock

All two-storey extension services in Matlock · First-floor extensions across Derbyshire

The quickest next step is a visit. We'll look at your house in Matlock and give you an honest view of the options.