What is a wraparound extension?

A wraparound extension combines a side return and a rear extension into one L-shaped addition. It gives the largest possible ground floor, often creating an open-plan kitchen, dining and living space across the whole width of the house.
How much does a wraparound extension cost in Boston?
In Boston, a wraparound extension typically costs £2,100–£3,050 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £59,000–£85,500. Building costs in the East Midlands run about 5% below the UK average, and the figures for Boston are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £42,000–£61,000 |
| Typical project (28 m²) | £59,000–£85,500 |
| Larger project (39 m²) | £82,000–£119,000 |
| Rate per m² | £2,100–£3,050 |
Your quote will depend mainly on:
- Drainage changes
- Steelwork and propping of the existing house
- Total footprint and the amount of glazing
- Access for materials on terraced streets
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a wraparound extension in Boston?
Before anything is built in Boston, we confirm which approvals apply in England. In England a wraparound extension combines side and rear elements, which normally takes it outside permitted development, so a householder planning application is made.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
The work we manage on a wraparound extension:
- Removal of internal and external walls
- Structural engineer’s design for steels and supports
- Underfloor heating option, electrics and plastering
- Foundations and drainage
- Party wall notices and surveyor liaison
- Walls, roof and glazing
How long does it take?
Allow 12 to 18 weeks on site. Before that, surveys, drawings and approvals usually take 3 to 4 months, longer if the council asks for changes.
Building in Boston
The East Midlands has a mix of red-brick terraces, inter-war semis and newer estates, so rear extensions and garage conversions are common projects.
Our Boston coverage includes postcode districts PE21, and we also work in nearby places such as Spalding, Skegness and Wisbech.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about wraparound extensions in Boston
Will both neighbours be affected?
Usually only the neighbour on the side return side, but rear foundations near either boundary can trigger party wall notices.
Does a wraparound extension need planning permission?
Almost always. Combining side and rear elements usually goes beyond permitted development limits, so a householder planning application is normally made.
Do you build wraparound extensions in Boston?
Yes. We build wraparound extensions across Boston, including postcodes PE21. Every project starts with a free home visit.
What about the old back addition?
The side wall of the back addition is usually removed and replaced with a steel beam, so the old kitchen joins the new space.
How much does a wraparound extension cost in Boston?
In Boston, a wraparound extension typically costs £2,100–£3,050 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £59,000–£85,500. Your fixed price depends on the survey and drawings.
