Mark Siwik

Senior Architect | Building Envelope Director

Mark Siwik, AIA, RRC has designed and repaired more than 350 roofs — when building owners have a leak, they call him. He conducts building envelope forensics to pinpoint the leak’s source, whether it’s on a roof or within a masonry wall. Mark has done single building and campus-wide assessments for facilities ranging from schools and hospitals to public works facilities and train stations.

Mark is one of few Registered Roof Consultants (RRC) in Illinois. The accreditation, issued by the International Institute of Building Enclosure Consultants (IIBEC), verifies “quantified, objective roofing expertise” in codes/standards, materials, assemblies, performance analysis, quality assurance, and testing methods.

He also observes the construction of projects designed by Legat. Mark relies on more than 30 years of experience to make sure owners get what they paid for in the plans and specifications. He ensures that contractors or construction managers correct all deficiencies.

Mark earned his architectural degree from Southern Illinois University.