Durham & County Durham
House Extensions in Durham
Alpine Extensions designs and builds bespoke home extensions throughout Durham and the surrounding parts of County Durham. Design, planning, Building Regulations and construction are all delivered by one team, under one contract.
Space, without the move
Stay where you are. Change what you have.
Outgrowing a house rarely means outgrowing the area. Extending lets you keep the street, the neighbours and the school run exactly as they are, and put the missing room where you actually need it.
No two homes we work on are alike. A stone-built property on the edge of a County Durham village asks for a very different approach to a 1970s semi with a long rear garden. Every design we produce starts from three things: the character of the existing house, the space realistically available around it, and how you want to use the new room once the builders have gone.
That might be a wide kitchen and dining space that finally seats everyone, a quieter sitting room away from the noise, or a bright garden room that works in February as well as July. Whatever the brief, the layout, glazing, ceiling heights and connection to the existing rooms are worked through with you before any price is fixed — and you can see it all in our completed projects or read more about Alpine Extensions.
What we build
Extensions we build in Durham
Four routes to more space, each designed around the property it belongs to.
One team, one contract
A complete design and build service
Most of the stress in an extension comes from managing separate companies. We carry the project from the earliest design conversations through to the final coat of plaster, so nothing falls between trades.
Design & approvals
- Initial home consultation
- 4D virtual design
- Architectural drawings
- Planning applications where required
- Building Regulations
- SAP calculations where required
- Structural calculations
Structure & envelope
- Groundworks and foundations
- Brickwork
- Roofing
- Windows and doors
- Insulation
Services & finish
- Electrics
- Plumbing
- Heating
- Plastering
- Project management
The extension is handed over plastered and ready to decorate, with heating, electrics and plumbing already in place. The remaining work is the enjoyable part: painting the walls and laying the flooring you have chosen.
How it works
Five clear stages
- 01
Free home consultation
We come to you, listen to what is not working in the house today and look honestly at what the plot allows.
- 02
4D virtual design
Your proposed extension is modelled so you can move through it and refine it before anything is agreed.
- 03
Planning & approvals
Drawings, planning submissions where needed, Building Regulations and calculations are all handled for you.
- 04
Construction
One managed programme, one site team and regular updates as the structure comes out of the ground.
- 05
Your new space
Handed over plastered and ready to decorate, with heating, electrics and plumbing already complete.
Recent work
Extension Projects in Durham & County Durham
Genuine Alpine Extensions projects, photographed on completion.
Where we work
House Extensions Across Durham & Surrounding Areas
Our team works throughout Durham City and the wider county — from terraces and townhouses close to the centre to village properties and larger detached homes out towards the dales.
- Durham City
- Chester-le-Street
- Lanchester
- Consett
- Stanley
- Sacriston
- Langley Moor
- Belmont
- Framwellgate Moor
- Bowburn
If your home sits just outside this list, it is still worth asking — we build across the North East, including Newcastle and the surrounding areas.
Why Alpine
Why choose Alpine Extensions?
Complete design and build service
Design, approvals and construction under one contract and one point of contact.
4D virtual extension designs
See exactly how the finished room will feel before committing to it.
Planning & Building Regulations managed
We prepare and submit the paperwork so you are not chasing it yourself.
10-year guarantee
Written cover on structure and workmanship for a decade after handover.
North East extension specialists
A family-run team building extensions across County Durham and the wider region.
Finance options available
Ways to spread the cost, discussed openly alongside your fixed quotation.
Award recognition
- G23 Awards — Finalist
- Installer Awards 2024 — Winner
- Business Awards 2023 — Winner
- G25 Awards — Finalist
Client words
Hundreds of five-star reviews
Fixed price meant fixed price. Not one extra invoice in fourteen weeks, and the site was spotless every Friday.
Questions
Durham house extension FAQs
How much does a house extension cost in Durham?+
There is no single figure, because cost follows the project. Size, design, specification, ground conditions and foundations, the amount of glazing and the individual requirements of your property all change the number. We prepare a detailed, itemised quotation for your specific extension once we have surveyed the house and worked through the design with you.
Do I need planning permission for a house extension in Durham?+
It depends on the property and what you are proposing. Some extensions qualify under Permitted Development rights, while others need a planning application to Durham County Council — and homes in conservation areas or with previous extensions are often treated differently. We assess the requirements for your home and manage whichever route applies.
Does Alpine handle Building Regulations for Durham extensions?+
Yes. Building Regulations, along with structural calculations and SAP calculations where they are needed, are managed as part of our complete extension service rather than left with you to arrange.
How long does a house extension take to build?+
That depends on the size, design and complexity of the project, and on whether planning approval is required beforehand. Rather than quote a headline timescale, we set out a realistic programme once the design is settled and the approvals position is clear.
Which areas of County Durham do you cover?+
We work throughout Durham and the surrounding areas, including Chester-le-Street, Lanchester, Consett, Stanley, Sacriston, Langley Moor, Belmont, Framwellgate Moor, Bowburn and other parts of County Durham.
How is the extension finished?+
We take care of the main construction work along with the electrics, plumbing, heating, insulation and plastering. Your extension is handed over plastered and ready to decorate, so the main things left to you are painting the walls and laying the flooring you choose.
Start your project
Thinking About Extending Your Durham Home?
Arrange a free consultation with our team to talk through your ideas, see what your property can take and receive a personalised quotation.
- Design consultation at your home or online
- Photoreal 4D walkthrough of your new space
- Fixed-price quotation within 7 days