Side return extensions across Lancaster
Lancaster homeowners can use us for the whole side return extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in LancasterFrom £17,000 inc VAT
- PlanningOften permitted development; party wall notice usual
- Build time10–14 weeks on site
- Postcode districtsLA1, LA4

Included in a typical project
- Glazed, sloping or flat roof with rooflights
- Design to keep daylight in the middle of the house
- Survey of the outrigger, boundary wall and drainage
- New boundary wall or raised party wall
- Kitchen-ready shell or full finish
Local to Lancaster
Across LA1, LA4, we can visit, measure and advise. Nearby, we also take on projects in Morecambe (3 miles), Fleetwood (12 miles), Thornton-Cleveleys (15 miles), Poulton-le-Fylde (17 miles).
Just over the Cumbria border, Ulverston is about 16 miles away. Across the North West, terraced houses with small rear yards suit compact rear and side return extensions, while suburban semis have room for more.
Will the council need to approve it?
In England a single-storey side return infill is often permitted development if it stays within the height limits and is no wider than half the width of the original house. Conservation areas, listed buildings and flats always need an application, and the boundary wall usually brings in the Party Wall Act.
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 over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
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 much does a side return extension cost in Lancaster?
These guide figures apply our North West England adjustment (×0.95) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Lancaster: £2,000 to £3,610 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 1.8 m × 4.5 m 8 m² | £17,000 – £20,500 | £18,000 – £23,000 | £22,500 – £29,000 |
| 2 m × 5.5 m 11 m² | £21,500 – £26,500 | £25,000 – £31,500 | £31,000 – £40,000 |
| 2.2 m × 7 m 15 m² | £29,500 – £36,000 | £34,000 – £43,000 | £42,500 – £54,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
From first visit to completion
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Common questions in Lancaster
Do you cover all of Lancaster?
Yes. We cover Lancaster and the surrounding parts of Lancashire. Site visits are free and there is no obligation.
Who do I contract with for a side return extension in Lancaster?
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 see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Lancaster, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How much does a side return extension cost?
Our guide range is about £2,000 to £3,610 per m² including VAT, so a typical 2 m × 5.5 m infill lands around £25,000 to £31,500 at standard spec in Lancaster, more in London.
Will the kitchen be darker?
Not if the roof is designed well. A glazed roof or a line of rooflights along the boundary usually makes the room brighter than before.
Book a free site visit in Lancaster
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.