The People Behind the Practice
Vertex Building Consultancy was founded on a simple belief: every property decision deserves clarity, not guesswork. Meet the team bringing decades of combined expertise to clients across Dublin and beyond.
Built on Trust, Driven by Expertise
Vertex was established in Dublin to fill a gap we saw firsthand: too many property decisions were being made with incomplete information, leaving homeowners, buyers, and investors exposed to unnecessary risk.
Our co-founders bring together complementary skill sets — deep technical surveying expertise, regulatory knowledge spanning Irish and European building standards, and a practical, client-first approach shaped by years of working directly with property owners.
From a two-person operation working out of a shared office on Merrion Square, we have grown into one of Dublin’s most trusted independent building consultancies — serving homeowners, landlords, investors, solicitors, and commercial clients across Leinster.
What sets us apart isn’t just technical competence — it’s the way we communicate. Every report we produce is designed to be understood and acted upon, not filed away. We believe expertise only matters if it leads to better decisions.
Leadership & Expertise
Our directors combine technical excellence with a genuine commitment to client outcomes.
Ciarán O’Sullivan
Co-Founder & Managing Director · Chartered Building Surveyor
Ciarán is a Chartered Building Surveyor with over 18 years of experience across the Irish and UK construction sectors. He began his career with a leading Dublin-based multidisciplinary practice, where he led building surveying commissions for institutional investors, local authorities, and private clients across the residential, commercial, and heritage sectors.
He holds a BSc (Hons) in Building Surveying from Technological University Dublin and is a Chartered Member of the Society of Chartered Surveyors Ireland (SCSI) and the Royal Institution of Chartered Surveyors (RICS). Ciarán is also a registered Building Energy Rating (BER) assessor with the Sustainable Energy Authority of Ireland (SEAI).
His expertise spans pre-purchase building surveys, dilapidation assessments, defect diagnosis, expert witness services, and technical due diligence for property transactions. Ciarán is known for his forensic approach to building pathology — he prides himself on identifying issues that others miss.
Aoife Brennan
Co-Founder & Technical Director · Architectural Technologist & BER Specialist
Aoife is an Architectural Technologist and certified BER assessor with 15 years of experience spanning architectural practice, energy consultancy, and building regulation compliance. She previously led the technical design team at a prominent Dublin architecture firm, delivering residential and mixed-use projects from concept through to completion.
She holds a BSc in Architectural Technology from ATU Galway and a Postgraduate Diploma in Building Performance and Energy Assessment. Aoife is a Chartered Architectural Technologist (CIAT) and a registered Non-Domestic BER assessor with SEAI, qualified to assess both new and existing buildings across all energy rating categories.
Aoife specialises in building performance analysis, energy retrofit strategies, technical design consultancy, and regulatory compliance advisory. She has a particular passion for helping homeowners navigate the complexities of Ireland’s evolving building regulations and energy standards — translating dense technical requirements into clear, actionable guidance.
Qualifications & Memberships
Our practice is built on a foundation of recognised professional standards and continuous development.
Chartered Surveyors
Chartered membership with the Society of Chartered Surveyors Ireland (SCSI) and the Royal Institution of Chartered Surveyors (RICS) — the gold standard for building surveying professionals.
SEAI Registered Assessors
Fully registered Building Energy Rating assessors with the Sustainable Energy Authority of Ireland for both residential and non-domestic building assessments.
Chartered Architectural Technologist
Chartered membership with the Chartered Institute of Architectural Technologists (CIAT), reflecting expertise in building design, technology, and regulatory compliance.
NZEB & Retrofit Design
Certified Nearly Zero Energy Building (NZEB) designer, qualified to advise on deep retrofit strategies and energy performance optimisation for new and existing buildings.
Expert Witness
Experienced in providing expert witness testimony for building disputes, dilapidation claims, and construction defect litigation in Irish courts and mediation proceedings.
Professional Indemnity
Fully insured with comprehensive professional indemnity and public liability coverage, giving clients complete peace of mind on every commission.
Media Appearances & Publications
Our directors regularly contribute expert commentary to Irish media on property, building regulations, and construction quality.
The Irish Times · March 2025
“What Every Homebuyer Needs to Know Before Signing Contracts”
Ciarán O’Sullivan contributed expert commentary on the importance of pre-purchase building surveys, highlighting common hidden defects and the financial risks of skipping due diligence.
The Irish Times · March 2025
“What Every Homebuyer Needs to Know Before Signing Contracts”
Ciarán O’Sullivan contributed expert commentary on the importance of pre-purchase building surveys, highlighting common hidden defects and the financial risks of skipping due diligence.
The Irish Times · March 2025
“What Every Homebuyer Needs to Know Before Signing Contracts”
Ciarán O’Sullivan contributed expert commentary on the importance of pre-purchase building surveys, highlighting common hidden defects and the financial risks of skipping due diligence.
The Irish Times · March 2025
“What Every Homebuyer Needs to Know Before Signing Contracts”
Ciarán O’Sullivan contributed expert commentary on the importance of pre-purchase building surveys, highlighting common hidden defects and the financial risks of skipping due diligence.
Ready to Discuss Your Project?
Get in touch for a free initial consultation. We will discuss your needs, answer your questions, and outline how we can help — with no obligation.