Grimsby bedroom extensions, designed and built
Grimsby homeowners can use us for the whole bedroom extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in GrimsbyFrom £24,500 inc VAT
- PlanningUsually a householder application
- Build time14–22 weeks on site
- Postcode districtsDN31, DN32, DN33, DN34, DN35
Extensions in and around Grimsby
Our survey diary covers Grimsby, including DN31, DN32, DN33, DN34, DN35, DN37. Neighbouring towns we cover include Cleethorpes (2 miles), Scunthorpe (24 miles), Lincoln (30 miles), Gainsborough (31 miles).
Hull, in East Riding of Yorkshire, is roughly 16 miles from Grimsby and also on our list. Homes across the East Midlands often have usable side land or a driveway beside the house, which opens up side and wraparound options.
When a bedroom extension makes sense
- Growing families
- Multi-generational households
- Homeowners who want an en-suite master bedroom
New bedrooms on an upper floor need an escape window or a protected route to the outside under the building regulations. We design the window sizes and stair route to meet that from the outset.
Bedroom extension prices in Grimsby
Labour and material costs vary across the UK, so for Grimsby we use our East Midlands factor (×0.95). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Grimsby: £1,520 to £3,040 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| One bedroom 12 m² | £24,500 – £30,500 | £24,500 – £32,000 | £27,000 – £36,500 |
| Bedroom and en-suite 18 m² | £27,000 – £33,500 | £32,000 – £42,000 | £41,000 – £55,000 |
| Two rooms 30 m² | £45,500 – £56,000 | £54,000 – £70,000 | £68,000 – £91,500 |
Try the guide-price tool to see a range for your own size and finish.
Do I need planning permission in Grimsby?
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Bedroom extension questions answered
How long does a bedroom extension take to build in Grimsby?
On site, typically 14 to 22 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Do I need building regulations approval in Grimsby?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who do I contract with for a bedroom extension in Grimsby?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I add a ground-floor bedroom for a relative?
Yes. A ground-floor bedroom with an accessible shower room is a common request. If it will be lived in as a self-contained home, planning treats it differently, so tell us how it will be used.
Will a new bedroom need planning permission?
Upstairs additions usually do. Ground-floor rooms may fall within permitted development, depending on size and position.
Book a free site visit in Grimsby
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.