Boston house extensions
We design and build house extensions for homes in Boston and the surrounding Lincolnshire area, with guide prices adjusted for the region.
- Postcode districtsPE21
- Price regionEast Midlands (×0.95)
- Planning rulesEngland
- Site visitFree, no obligation
Popular extension prices in Boston
We publish guide prices so you can budget before anyone visits. For Boston they are adjusted by ×0.95, the factor we use across East Midlands.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Side return extensions | 11 m² | £25,000 – £31,500 |
| Orangery extensions | 16 m² | £42,500 – £53,500 |
| Double-storey extensions | 32 m² | £54,500 – £71,500 |
| Wraparound extensions | 25 m² | £54,500 – £69,000 |
| Extensions over a garage | 12 m² | £23,500 – £31,000 |
| Single-storey rear extensions | 20 m² | £38,500 – £49,500 |
| Kitchen extensions | 20 m² | £39,500 – £50,500 |
Covering Boston and nearby
Our survey diary covers Boston, including PE21. The same team covers Spalding (14 miles), Skegness (19 miles), Grantham (26 miles), Lincoln (27 miles), Stamford (30 miles), all within easy reach. Wisbech, in Cambridgeshire, is roughly 23 miles from Boston and also on our list.
Approvals for an extension in Boston
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
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.
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).
Which extension suits a Boston home?
The East Midlands has plenty of inter-war and post-war semis and detached houses with room to extend, alongside Victorian terraces in the towns.
The types we would usually look at first for a home in Boston are conservatory replacement extensions, single-storey rear extensions and side extensions, depending on the garden and how the house is laid out.
All extension types we build in Boston
- Flat roof extensions · from £19,500
- Planning permission for extensions · from £300
- Side extensions · from £20,500
- Utility and boot room extensions · from £13,000
- Extension plans and drawings · from £1,100
- Annexe extensions · from £52,000
- Side return extensions · from £17,000
- Timber frame extensions · from £19,500
- Kitchen extensions · from £25,500
- Bedroom extensions · from £24,500
- Porch extensions · from £3,800
- Bungalow extensions · from £24,500
- Glass box extensions · from £28,500
- Double-storey extensions · from £36,000
- Single-storey rear extensions · from £19,500
- Wraparound extensions · from £34,000
- Building regulations for extensions · from £850
- Pitched roof extensions · from £21,000
- Extensions over a garage · from £22,500
- Orangery extensions · from £28,500
- Conservatory replacement extensions · from £19,000
- Home office extensions · from £15,000
Free site visit
We visit your Boston home, measure up, talk through what you want and check the planning position.
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
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions about extensions in Boston
How much does an extension cost in Boston?
Using our East Midlands factor (×0.95), a standard-spec single-storey extension of 20 m² is a guide £38,500 to £49,500 including VAT, and a 32 m² two-storey extension £54,500 to £71,500. Your written price follows the survey.
How long does an extension take in Boston?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Boston, and the guide-price tool gives a range for your own size and finish in about a minute.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Who do I contract with?
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.
Book a free site visit in Boston
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.