One team. One process. No compromises.
Oneoff Design is an architectural design studio built around a single idea: that every project deserves the same level of care, precision, and ambition — whether it's a rear extension or a new build from the ground up.
Built on the belief that good design should be accessible.
We started Oneoff Design because we saw too many homeowners and developers navigating a fragmented process — architects who didn't do planning, planners who didn't do drawings, project managers who arrived too late. The result was delays, cost overruns, and buildings that fell short of what they could have been.
So we built a studio that does it all in-house. Design, CAD, 3D visualisation, planning applications, building control, and project management — handled by one team, under one roof, from first sketch to final sign-off.
That's the Oneoff difference. One point of contact. One clear process. One team that's invested in your project from day one.
Our values
Precision
Every drawing, every calculation, every detail is produced to the highest standard. We don't cut corners — in design or in process.
Clarity
We communicate plainly. No jargon, no surprises. You'll always know where your project stands and what comes next.
Ambition
We push every project to be the best version of itself. Good enough is never the goal.
Accountability
One team means one point of responsibility. If something needs fixing, we fix it — no finger-pointing between consultants.
The people behind the work.
James Butcher
Founder & Lead DesignerJames founded OneOFF Design after a decade working across residential and commercial practices in Hampshire & London. He leads design on every project, ensuring the studio's standards are upheld from concept to completion.
Sean Punnett
CAD Technician designerSean designs CAD drawings with specification, bringing precision and technical detail to every project. His work covers measured surveys, planning drawings, building regulations packages, and fully coordinated construction details across residential and commercial schemes.
Qualified, insured, and experienced.
Professional Indemnity Insurance
Fully insured for professional indemnity and public liability, giving you complete peace of mind throughout your project.
25+ Years Experience
Over two decades of residential and commercial projects across London and the South East, from single-room extensions to multi-unit new builds.
Ready to start?
Tell us about your project. We'll tell you exactly how we can help.