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PB_ARC is a residential architecture practice specialising in house extensions, sensitive redesigns, and bespoke new-build homes. Founded in 2020 by Ruairi Cassidy, the studio is driven by thoughtful, well-crafted domestic architecture.
Ruairi completed his architectural education with a BSc in Architecture from Sheffield, an MArch from Nottingham, and a PGDip from UCL, becoming a chartered architect registered with the ARB in 2018. The practice initially focused on small-scale residential extensions across North London and the surrounding Boroughs, before naturally evolving into larger, more complex projects and new-build homes.
PB_ARC has developed extensive experience working within areas of planning constraint, including Conservation areas, Green belt locations, and Grade II Listed buildings. This expertise allows the studio to balance creative ambition with a clear understanding of planning policy and context.
In 2025, PB_ARC submitted over 60 planning applications and managed 18 on-site projects, overseen by Ruairi alongside a small team of Architect Assistants.
Today, PB_ARC’s portfolio spans London, the surrounding Boroughs and the wider UK, with a reputation for considered design, technical rigour, and a collaborative approach from concept through to completion.
We offer a free Design Consultation for your project to discuss feasibility, constraints and development possibilities, so feel free to email or call!
PBARC LTD, Company number 13289299
1: Design and Planning
All of our projects are developed using the latest 3D modelling technology, enabling a clear and comprehensive understanding of space, scale, and spatial quality from the outset. Our fees are fixed from the outset and include design development, allowing for design changes and iterations as the scheme evolves. Once the design is agreed, we prepare and submit the planning application and act as your agent throughout the planning process.
2. Building Control
Following the grant of planning consent, we offer a comprehensive technical design package addressing all building regulations and statutory requirements. The drawings and specifications are developed in detail to enable competitive tendering by contractors. We coordinate closely with structural engineers and approved inspectors as required, ensuring the scheme is fully approved and signed off prior to works commencing on site.
3. On Site
An optional site management service is available to safeguard design quality and ensure the project is delivered in line with the original vision. This can be provided on an ad hoc basis or incorporated as part of a full-service appointment which will include internal elevations and detailed room by room specifications.