House Extensions in Barnet
Barnet is one of North London's most active markets for larger extensions, loft conversions and full refurbishments. Generous plots across N2, N3, N12 and N20 make substantial extension work viable.
rcbGroup projectHouse Extensions in Barnet — what to expect
Barnet's detached and semi-detached stock suits generous extensions. Prior approval 8m rear extensions are common on detached properties. Double-storey side extensions, wraparound extensions and garage conversions are all active project types. East Barnet and Friern Barnet (N11, N12) have particularly good extension potential.
Barnet property types
Interwar and post-war detached and semi-detached, Victorian terraces near New Barnet and High Barnet. The property type affects which extension approach works best — we'll advise from the first call.
Common extension projects we deliver in Barnet
How we deliver extension projects in Barnet
Project review & site visit
We look at your Barnet property and any drawings you have, explain what's possible, the likely planning and Building Regulations route, and the risks — before you commit to anything. No obligation.
Design & planning support
We work alongside your architect or our preferred design partners to develop drawings that are buildable, compliant, and cost-effective. We flag planning and permitted development options early.
Itemised scope and price
You receive a detailed, itemised scope of works and an agreed price before we start, with exclusions and provisional sums shown. Variations are agreed in writing before any additional work begins.
Managed delivery
We coordinate trades, procurement and site logistics, with a single point of contact throughout — working to the requirements of London Borough of Barnet and Building Control.
Sign-off & handover
We coordinate the Building Control inspections needed for sign-off, then hand over your project documents — completion certificate, guarantees and manuals as applicable — with snagging and aftercare as set out in your contract.
Planning in Barnet
Barnet has Green Belt land in Totteridge, Mill Hill and the northern borough edges. Extension potential is restricted for Green Belt properties. Conservation areas exist in East Barnet, Whetstone and Barnet town. Verify with LBBarnet Planning.
Why choose rcbGroup in Barnet?
Local context
We plan around London Borough of Barnet's requirements and the typical property types in Barnet — interwar and post-war detached and semi-detached, victorian terraces near new barnet and high barnet.
Price agreed before start
Your price is agreed and documented before work starts. Scope, exclusions, and assumptions set out in writing.
One accountable team
Trades, suppliers and inspections coordinated by one team — with CDM Principal Contractor duties taken on where we are appointed to build.
Written project documentation
A written contract before work starts, a Construction Phase Plan where we are appointed to build, and the completion certificate and handover documents gathered for you at the end.
Independently reviewed
Rated 10/10 from 117+ reviews on Checkatrade, where you can read them for yourself.
Support from planning to aftercare
We don't just build — we can support design development, planning applications, and pre-construction cost planning.
Planning an extension in Barnet?
Pick whatever suits you. We'll look at what you have (drawings, photos or quotes) and tell you honestly what the next step should be.
Prefer to phone? Call +44 7359 872594.
Postcodes served: Barnet
Not sure if we cover your street? Get in touch — we'll confirm in minutes.
Start your Barnet project
Project review. Clear scope. Agreed price. One team from first call to Building Control sign-off.
Or call us on +44 7359 872594