Grimsby, Lincolnshire
Single-storey rear extension in Grimsby
We plan and build single-storey rear extensions for homeowners in Grimsby. Ground-floor space across the back of the house, usually for a kitchen, dining or family room. Start with a free site visit, then a written price once the design is agreed.
Grimsby sits in Lincolnshire, with postcode districts including DN31, DN32 and DN34. On red-brick terraces and semis like those around Grimsby, a single-storey rear extension is usually the simplest way to fix a small back kitchen without touching the bedrooms.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a single-storey rear extension cost in Grimsby?
For Grimsby we work from the East Midlands rate: £1,840–£3,010 per square metre of new floor, including VAT, standard specification. East Midlands prices sit a little below our West Midlands baseline.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £22,000–£36,000 |
| 4 m wide × 5 m deep (20 m²) | £37,000–£60,000 |
| 4 m wide × 6 m deep (24 m²) | £44,000–£72,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a single-storey rear extension in Grimsby?
The planning route for a single-storey rear extension in Grimsby is set by England's householder rules and your council.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Grimsby like to extend?
Red-brick terraces and semis are typical of Grimsby. Coal-mining legacy areas in parts of the East Midlands can need a Coal Authority check before foundations are designed.
How a single-storey rear extension in Grimsby comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Single-storey rear extensions near Grimsby
From Grimsby, the nearest places we also cover are Cleethorpes (1.8 miles) and Immingham (6.7 miles).
- Single-storey rear extension in Cleethorpes
- Single-storey rear extension in Immingham
- Single-storey rear extension in Hedon
- Single-storey rear extension in Louth
- Single-storey rear extension in Kingston upon Hull
Other work in Grimsby:
FAQ
Single-storey rear extension questions in Grimsby
Is the site visit in Grimsby free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Do you handle building control in Grimsby?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
How deep can a single-storey rear extension be without planning?
In England, 3 metres on an attached house and 4 metres on a detached house under permitted development, or up to 6 and 8 metres with prior approval. Wales allows 4 metres; Scotland and Northern Ireland have their own limits.
Do I need planning permission for a rear extension in Grimsby?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.