Our Story
Built on Trust. Delivered with Pride.
For over two decades, OSS & Co has been turning ambitious visions into enduring structures. We're a construction company that takes the long view — on quality, on relationships, and on the communities we build in.
Who We Are
Two Decades of Building What Matters
OSS & Co was founded in 2004 by a small team of builders who believed that construction could be done differently — with more transparency, more care, and a genuine commitment to the people behind every project.
What started as a residential contractor has grown into a full-service construction company delivering complex projects across residential, institutional, and commercial sectors. Through every phase of growth, our founding values have remained unchanged.
Today, our team of over 120 professionals brings together expertise in project management, structural engineering, design coordination, and site delivery — all under one roof, all working toward the same goal: your project, done right.
20+
Years in business
What Drives Us
Our Values
Integrity
We say what we mean and do what we say. Honest communication and transparent reporting are non-negotiable on every project we take on.
Craftsmanship
We take pride in the quality of our work — from the structural frame to the final finish. Every detail matters because every detail lasts.
Collaboration
The best outcomes come from working closely with clients, architects, and consultants. We listen first, then build.
Accountability
We own our commitments. If something isn't right, we fix it. No excuses, no finger-pointing — just solutions.
The People Behind the Projects
Leadership Team
Oliver Sinclair
Founder & Managing Director
Oliver founded OSS & Co in 2004 after 12 years in commercial construction. His hands-on approach and client-first philosophy set the tone for everything the company does.
Sarah Okafor
Director of Operations
Sarah oversees project delivery across all sectors, ensuring every site runs safely, on schedule, and to the standard our clients expect.
James Whitfield
Head of Estimating & Commercial
James leads our commercial team, bringing rigour and transparency to every tender, contract, and cost plan we produce.
Priya Nair
Head of Design Coordination
Priya bridges the gap between design intent and construction reality, working closely with architects and engineers to keep projects buildable and on brief.
Accreditations & Memberships
Recognised. Certified. Trusted.
Master Builders Association
Full member since 2005
ISO 9001:2015
Quality Management Systems
ISO 45001:2018
Occupational Health & Safety
Green Building Council
Accredited builder member
LEED Accredited
Certified project delivery
Construction Industry Training Board
Registered employer
Let's Build Something Together
Whether you have detailed plans or just an idea, we'd love to hear about your project.