Grantham, Lincolnshire
Bungalow rear extension in Grantham
Single-storey rear extensions that keep everything on one level. If you live in Grantham and want to know what a bungalow rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
We cover Grantham (NG31) as part of our Lincolnshire work. For Grantham bungalows we design the roof first, because the low eaves decide the height of the new room.
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 bungalow rear extension cost in Grantham?
Guide prices for a bungalow rear extension in Grantham start from our East Midlands rate of £1,790–£2,910 per square metre, including VAT. East Midlands prices sit a little below our West Midlands baseline.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,500–£35,000 |
| 4 m wide × 6 m deep (24 m²) | £43,000–£70,000 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a bungalow rear extension in Grantham?
Whether your bungalow rear extension in Grantham needs a planning application depends on its size, your house and any local restrictions.
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.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Grantham like to extend?
Grantham has plenty of inter-war semis and bungalows, and single-storey rear extensions suit both.
How a bungalow rear extension in Grantham 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.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Bungalow rear extensions near Grantham
Neighbouring places we cover include Sleaford (11.4 miles) and Newark on Trent (13.0 miles).
- Bungalow rear extension in Sleaford
- Bungalow rear extension in Newark on Trent
- Bungalow rear extension in Melton Mowbray
- Bungalow rear extension in Bourne
- Bungalow rear extension in Oakham
Other work in Grantham:
FAQ
Bungalow rear extension questions in Grantham
Do I need planning permission for a rear extension in Grantham?
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.
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.
How deep can I extend?
The same limits as a house: 3 or 4 metres in England, more with prior approval.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
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.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.