Saltash · Cornwall

Two-storey side extensions in Saltash

Homes in Saltash with a bit of space to the side or rear can often take a two-storey side extension. We'll tell you honestly whether yours can, and what approvals it needs.

Before you start in Saltash, here's what applies.

Postcode districts
PL11 and PL12
County / area
Cornwall, England
Price region
South West England
Guide price
£88,500–£119,000 (£2,110–£2,830 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Plymouth (4.5 miles), Plymstock (6.9 miles), Tavistock (10.3 miles)
Distance to Truro
about 37.9 miles
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension suits a detached or semi-detached house with a side garden, driveway or garage wide enough to build on. You get a design that sits comfortably on the street, a planning application or permitted development check depending on your nation, structural design, building regulations approval and the build itself. We manage the whole process, and the work is carried out by vetted teams working under S&K.

Saltash sits about 37.9 miles from Truro. Closer to home, Plymouth is 4.5 miles away and Plymstock 6.9 miles.

What it costs in Saltash

Most of the cost of a two-storey side extension is set by its size and specification. For Saltash and the rest of South West England, our guide is £2,110–£2,830 per m² including VAT, so about £88,500–£119,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Keep a contingency of around 10% for things nobody can see until the ground is opened up.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£1,940–£2,610 per m²£81,500–£109,500
Standard£2,110–£2,830 per m²£88,500–£119,000
Premium£2,530–£3,400 per m²£106,500–£143,000

Planning and building regulations in Saltash

In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.

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 Saltash homes

Access and services

Side extensions often cover the only route to the back garden, a gas meter, soil pipes or a drain run. We plan bin and bike access, move meters and pipes where needed and check drains early, because these items affect both cost and layout.

Side windows, boundaries and gutters

Upstairs windows in the side wall face the neighbour, so they are usually obscure-glazed and fixed, or left out. Building close to the boundary also raises questions about foundations, overhanging gutters and access for maintenance, so we design the eaves and gutter to stay within your land.

How we'd run your project

  1. Free site visit

    We visit your home in Saltash, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  2. Get it approved

    Once you're happy with the design we submit it to the council for Saltash and deal with any questions from the planning officer.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about two-storey side extensions in Saltash

Which postcodes do you cover around Saltash?

We cover Saltash (PL11 and PL12) and nearby places including Plymouth, Plymstock and Tavistock, plus the rest of Cornwall. The first site visit is free.

Do I need planning permission for a two-storey side extension in Saltash?

Saltash is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How long does a two-storey side 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.

How much does a two-storey side extension cost in Saltash?

Our guide for South West England, which covers Saltash, is £2,110–£2,830 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £88,500–£119,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

Other towns near Saltash:

Other extensions in Saltash

All two-storey extension services in Saltash · Two-storey side extensions across Cornwall

Book a free site visit in Saltash and we'll tell you what's possible, what approvals you need and what the design stage would cost.

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