Double-storey extensions in Stockton-on-Tees: design, approvals and build
From the first sketch to final sign-off, we plan and build double-storey extensions in Stockton-on-Tees and the surrounding County Durham area.
- Guide price in Stockton-on-TeesFrom £34,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsTS16, TS17, TS18, TS19, TS20
Do I need planning permission in Stockton-on-Tees?
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
The planning position for a specific Stockton-on-Tees address depends on its history and any designations, which is why we check it at the first visit.
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.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
Local to Stockton-on-Tees
Our survey diary covers Stockton-on-Tees, including TS16, TS17, TS18, TS19, TS20, TS23. The same team covers Billingham (2 miles), Thornaby-on-Tees (3 miles), Yarm (5 miles), Hartlepool (9 miles), all within easy reach.
For homes towards North Yorkshire, Middlesbrough is around 3 miles away. The North East has many brick terraces, colliery-era housing and post-war semis, with rear extensions and kitchen extensions the most common requests.
When a double-storey extension makes sense
- Growing families who need a bedroom as well as a bigger kitchen
- Homeowners who would otherwise consider moving
- Houses with enough distance to the rear or side boundary
Double-storey extension prices in Stockton-on-Tees
For Stockton-on-Tees we adjust our national guide rates by ×0.91, the factor we use for North East England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Stockton-on-Tees: £1,410 to £2,730 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £34,500 – £41,500 | £39,000 – £51,500 | £50,000 – £66,000 |
| 4 m × 4 m, two floors 32 m² | £45,000 – £54,000 | £52,000 – £68,500 | £66,500 – £87,500 |
| 4 m × 6 m, two floors 48 m² | £67,500 – £81,000 | £78,500 – £103,000 | £100,000 – £131,500 |
Try the guide-price tool to see a range for your own size and finish.
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Double-storey extension questions answered
Who do I contract with for a double-storey extension in Stockton-on-Tees?
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.
Do you cover all of Stockton-on-Tees?
Yes. We cover Stockton-on-Tees and the surrounding parts of County Durham. Site visits are free and there is no obligation.
Will my neighbours in Stockton-on-Tees be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Do I need a Party Wall Agreement?
If you are in England or Wales and the work involves a shared wall or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We tell you which notices are needed.
Is a two-storey extension cheaper per square metre?
Usually. Our guide range is about £1,410 to £2,730 per m² of new floor area including VAT, compared with £1,590 to £3,090 per m² for single-storey work, because the foundations and roof are shared across two floors.
Book a free site visit in Stockton-on-Tees
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.