Client: Castlethorn
Project Manager: Lafferty
Main Contractor & PSCS: Built
Architect: O’Mahony Pike Architects
QS: Castlethorn
M&E Consultant: Waterman Moylan
Building Liaison: McGovern Projects
Acoustic Consultant: AWN Consulting
Size: 9,000 sq. ft.
Castlethorn, one of Ireland’s leading residential developers, required a new head office on the sixth floor of a mixed-use building adjacent to Dundrum Town Centre. The brief was to transform a long-vacant floorplate into a high-spec, acoustically controlled workspace that reflected their brand’s precision, professionalism, and quality standards.
The project demanded a fast turnaround and a meticulous focus on confidentiality. With lower floors of the building fully occupied and strict noise and access restrictions in place, the challenge was to deliver a seamless fit out within a live suburban environment while maintaining premium standards of finish and performance.
Built Interiors was engaged early in the process - before the final design was complete - to provide pre-construction insight and early contractor involvement (ECI). This collaborative approach allowed design development and construction to progress simultaneously, compressing the programme while improving buildability and cost certainty.
The scope included a full strip-out and complete refit of the 9,000 sq. ft. space. Works comprised partitions, ceilings, extensive built-in joinery, fitted furniture, AV integration, and a detailed acoustic treatment plan. The architectural design by O’Mahony Pike balanced openness with controlled acoustics, demanding precise coordination across trades.
Located beside Dundrum Town Centre, the site presented multiple logistical and operational constraints. The service yard was shared with retail tenants, meaning Built had to schedule just-in-time deliveries and limit waste removal to a single skip at any given time.
A dedicated lift was assigned to the project, but access for larger elements - such as FCUs and glazed partitions -required an early morning crane lift at 5am on a Bank Holiday Sunday, carefully coordinated with building management (McGovern Projects).
Strict noise restrictions meant all loud works had to take place before 9am and after 5pm. Built implemented a detailed sequencing plan to maintain progress without disrupting neighbouring occupiers.
The design was still evolving as construction began. Built’s ECI approach turned that potential challenge into an advantage. Weekly coordination meetings brought together the client, Lafferty PM, O’Mahony Pike Architects, Waterman Moylan, and Built to review drawings, agree layouts, and make timely buildability adjustments.
This approach allowed the team to progress with strip-out, framing, and ceiling works while architectural details were being finalised. It saved an estimated four to six weeks on programme and avoided the costly redesigns that typically arise when construction begins too late in the design cycle.
Confidentiality was a central requirement for Castlethorn’s new HQ. The acoustic design, led by AWN Consulting, was developed to ensure minimal sound transfer between rooms, meeting spaces, and open-plan zones.
Built worked closely with AWN to integrate acoustic performance into the architecture—through specialist glazing, acoustic baffles, and partition wall treatments. Early engagement made it possible to design these elements into the construction sequence, rather than retrofit them later, ensuring both aesthetic and technical goals were met.
“By starting early, we effectively saved four to six weeks on the programme,” explains Alan McCormack, Senior Quantity Surveyor at Built. “That time saving alone represented a major commercial advantage for the client.”
Early Contractor Involvement also ensured that joinery - central to O’Mahony Pike’s design - was delivered to the highest standard. Collaborative design workshops were held between the architect, client, joinery manufacturer, and Built to review shop drawings and align finish expectations before fabrication began.
Alan Russell, Contracts Manager at Built, notes: “ECI improves buildability, mitigates risk, and drives certainty across time, quality, and value. It brings the contractor’s expertise into the design process when it matters most.”
All waste materials from the strip-out and refit were handled through approved recycling partners, achieving a certified recycling rate of approximately 97%.
Built’s environmental procedures ensured full compliance with the building’s operational standards and local environmental guidelines, coordinating closely with McGovern Projects for method statement approvals and access protocols.
The project was completed within the 14-week programme and to a finish standard that reflected the client’s reputation for quality. The final space balances design elegance with practical performance - high acoustic comfort, refined detailing, and efficient systems integration.
By adopting an early contractor involvement model, Castlethorn gained measurable value: a faster programme, improved coordination, and enhanced confidence in delivery. The result is a workspace that demonstrates how collaboration, technical precision, and early engagement deliver certainty from day one.
