Two-storey wraparound extensions in Grantham

The basics for Grantham at a glance.

Postcode districts: NG31, NG32 and NG33
County / area: Lincolnshire, England
Price region: East Midlands
Guide price: £118,000–£162,000 (£2,110–£2,890 per m²)
Approval route: Planning permission is needed: the side part takes it outside permitted development in England.
Nearest towns: Sleaford (11.4 miles), Newark-on-Trent (13 miles), Greetham (13.2 miles)
Distance to Lincoln: about 22.2 miles
First visit: Free, no obligation

About a two-storey wraparound extension

A two-storey wraparound extension is an L-shaped addition that extends both the side and the rear of your house, on two floors. It gives one of the largest gains in floor space of any extension, typically a big open-plan kitchen and living area below and two or more bedrooms or bathrooms above. In England it needs planning permission, because the side part is more than one storey.

Around Grantham we also work in Sleaford, Newark-on-Trent and Greetham, and across the rest of Lincolnshire. Postcode districts in and near Grantham: NG31, NG32 and NG33.

What it costs in Grantham

For budgeting in Grantham, allow around £118,000–£162,000 for a two-storey wraparound extension with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). That's based on £2,110–£2,890 per m² including VAT for the East Midlands. 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	An L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space)
Essential	£1,940–£2,660 per m²	£108,500–£149,000
Standard	£2,110–£2,890 per m²	£118,000–£162,000
Premium	£2,530–£3,470 per m²	£141,500–£194,500

Planning and building regulations in Grantham

In England, a two-storey wraparound extension needs householder planning permission, because any extension beyond a side wall must be single storey to be permitted development. The application costs £548 (or £575 for applications made from 8 December 2026). Councils weigh the side part against the street scene and the rear part against neighbours' light and outlook, and should decide within 8 weeks of validation.

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 Grantham homes

Daylight to the middle

A deep L-shaped plan can leave the middle of the ground floor dark, because the old rear rooms are now enclosed. We use wide rear openings, a well-placed stair and, where part of the extension is single storey, roof lights, while keeping total glazing within the Part L allowance.

The corner post

At the outside corner of the L, there is no existing wall to carry the floor above. Opening the ground floor fully usually means a steel frame or a corner post, and the engineer's design sets how slim it can be. We decide early whether you want a clear corner or a visible post.

How we'd run your project

Measure and listen
A visit to Grantham to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
Drawings, then consent
We draw the scheme, check it against the rules in England, and take it through the right consent with the council.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about two-storey wraparound extensions in Grantham

How long does a two-storey wraparound extension take?

Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.

Do I need planning permission for a two-storey wraparound extension in Grantham?

Grantham is in England, so England planning rules apply. Planning permission is needed: the side part takes it outside permitted development in England. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How much does a two-storey wraparound extension cost in Grantham?

Our guide for the East Midlands, which covers Grantham, is £2,110–£2,890 per m² including VAT. A typical project with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space) comes to about £118,000–£162,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Can I stay at home during a wraparound extension?

Many people do, but a wraparound affects two sides of the house and usually the kitchen, so there will be weeks without a full kitchen. We plan a temporary kitchen, keep a route through the house and seal off the work area. For some families, moving out while the rear wall is opened up is easier.

Is a wraparound extension better than separate side and rear extensions?

Building both at once usually costs less than two separate projects, because you pay for one set-up, one scaffold, one roof junction and one set of approvals. It also lets the layout be designed as a whole. The trade-off is a larger single outlay and a longer build, often 16 to 24 weeks at this size.

Nearby

We also cover places near Grantham, including:

Other extensions in Grantham

All two-storey extension services in Grantham · Two-storey wraparound extensions across Lincolnshire

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.