Preserving Building Integrity.
Securing Asset Value.

Premier building envelope consultation, design, and condition analysis.

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Our Services

Comprehensive solutions for building longevity and performance. Click a discipline to learn more.

Roof Consulting

  • Roof Condition Assessments
  • Leak Investigations
  • Infrared Services
  • Design Services
  • Tendering Services
  • Contract Admin / PM
  • Quality Assurance
  • Expert Witness
  • Testing Services
  • Safety Reviews

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Building Envelope

  • Envelope Condition Assessments
  • Water/Air Leakage Investigations
  • Infrared Services
  • Design Services
  • Tendering Services
  • Contract Admin / PM
  • Quality Assurance
  • Expert Witness
  • Testing Services
  • Safety Reviews

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Waterproofing

  • Waterproofing Condition Assessments
  • Infiltration Investigations
  • Design Services
  • Tendering Services
  • Contract Admin / PM
  • Quality Assurance
  • Expert Witness
  • Testing Services
  • Safety Reviews

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The Importance of Building and Roof Condition Assessments

Conducting regular building and roof condition assessments is essential for maintaining the integrity and value of your property.

Preventive Maintenance

Identifying potential issues early allows for timely repairs, preventing minor problems from escalating into costly repairs or replacements.

Safety Assurance

Ensuring the structural soundness of your building and roof protects the safety of all occupants, reducing the risk of accidents and injuries.

Financial Planning

Accurate assessments provide critical data for budgeting and financial planning, helping you allocate resources effectively for maintenance and repairs.

Energy Efficiency

A well-maintained building and roof enhance energy efficiency, leading to lower utility bills and a reduced environmental impact.

Regulatory Compliance

Regular assessments ensure your property meets local regulations and standards, avoiding potential fines and legal issues.

Longevity

Routine maintenance extends the lifespan of your building and roof, safeguarding your investment and ensuring long-term functionality.

Property Value

Maintaining your property in top condition enhances its market value, which is beneficial if you plan to sell or lease in the future.

MDS Building Science Inc. can assist building owners with comprehensive assessment services. Our team of experts is equipped to provide thorough evaluations and actionable insights to keep your property in optimal condition.

Recent Projects

From complex roof replacements to new construction monitoring.

Latest News & Insights

Stay updated with our latest field updates, industry insights, and technical announcements from LinkedIn.

MDS Building Science
BSAO Board Nomination
BSAO Board Nomination – Chris McConnell
We are proud to announce that Chris McConnell, B.Tech., Principal & Director of Buildings and Restoration, has been nominated for the BSAO Board of Directors!
Denis Theriault
OIRCA Golf Tournament
OIRCA Golf Tournament
Fantastic day out on the course at this year's OIRCA golf tournament! MDS Building Science had a great time golfing alongside HB Consultants and Polyglass.
MDS Building Science
Roof Preparedness & Failure Analysis
Is Your Building's Roof Prepared for the Next Storm?
Following severe weather roof collapses in Etobicoke and New Jersey, learn why rooftop maintenance and condition assessments are critical to avoiding catastrophic failure.
MDS Building Science
Happy Canada Day
Happy Canada Day!
Happy Canada Day from MDS Building Science Inc. May your celebrations be fun, safe, and hydrated in this heat!
MDS Building Science
IIBEC Southern Ontario Golf Outing
IIBEC Southern Ontario Chapter Golf Outing
Thank you Polyglass USA, HB Consultants, PDSB, W. R. MEADOWS, and Multiseal for a fantastic day at the IIBEC Southern Ontario Chapter Golf Outing!
Chris McConnell
Below-Grade Waterproofing Performance
Below-Grade Construction & Waterproofing Risks
As construction recovers, foundation waterproofing reliability is vital. Widespread failures of blindside systems can result in remediation costs upwards of $500k to millions.
MDS Building Science
BSAO Board Nomination
BSAO Board Nomination – Chris McConnell
We are proud to announce that Chris McConnell, B.Tech., Principal & Director of Buildings and Restoration, has been nominated for the BSAO Board of Directors!
Denis Theriault
OIRCA Golf Tournament
OIRCA Golf Tournament
Fantastic day out on the course at this year's OIRCA golf tournament! MDS Building Science had a great time golfing alongside HB Consultants and Polyglass.
MDS Building Science
Roof Preparedness & Failure Analysis
Is Your Building's Roof Prepared for the Next Storm?
Following severe weather roof collapses in Etobicoke and New Jersey, learn why rooftop maintenance and condition assessments are critical to avoiding catastrophic failure.
MDS Building Science
Happy Canada Day
Happy Canada Day!
Happy Canada Day from MDS Building Science Inc. May your celebrations be fun, safe, and hydrated in this heat!
MDS Building Science
IIBEC Southern Ontario Golf Outing
IIBEC Southern Ontario Chapter Golf Outing
Thank you Polyglass USA, HB Consultants, PDSB, W. R. MEADOWS, and Multiseal for a fantastic day at the IIBEC Southern Ontario Chapter Golf Outing!
Chris McConnell
Below-Grade Waterproofing Performance
Below-Grade Construction & Waterproofing Risks
As construction recovers, foundation waterproofing reliability is vital. Widespread failures of blindside systems can result in remediation costs upwards of $500k to millions.
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Leadership & Experience

Denis Theriault, RRO

Principal, Managing Director

Denis Theriault is a seasoned professional with over 25 years of experience in the roofing and building enclosure industry. While his primary strength lies in roofing, he has accumulated significant expertise in waterproofing, cladding, and fenestration.


Denis has led multiple complex projects with a focus on technical excellence, client satisfaction, and team collaboration. His technical repertoire includes conducting Roof and Building Condition Assessments, pre-performance audits, and legal reviews.


A recognized leader in the field, Denis is a Registered Roof Observer (RRO). He has dedicated over a decade to the IIBEC board, serving as President in 2020-2021 and currently directing the Advocacy Committee.

  • ✅ Registered Roof Observer (RRO)
  • ✅ IIBEC Past President (2020-2021)
  • ✅ IIBEC Advocacy Director (2025-Present)
  • ✅ 25+ Years Experience
Denis Theriault, RRO, Principal

Chris McConnell, B.TECH.

Principal, Director of Buildings and Restoration

Chris McConnell brings over 15 years of extensive experience to MDS Building Science Inc., with a specialized focus on the design and installation of waterproofing systems for both new construction and the rehabilitation of existing structures.


Holding a Bachelor’s degree in Infrastructure Engineering Technology (Summa Cum Laude), Chris possesses a talent for identifying complex construction challenges and providing practical, economical solutions. His expertise extends well beyond waterproofing to include intricate parking garage restorations, exterior façade assessments, and forensic water leak investigations.


Chris leverages his deep understanding of engineering principles to systematically diagnose failure mechanisms. By looking at problems from "outside the box," he develops long-term, warrantable solutions that protect client investments.

  • ✅ B.Tech., Infrastructure Engineering Technology
  • ✅ 15+ Years Industry Experience
  • ✅ Specialist in Forensic Waterproofing Investigations
  • ✅ BCRAO (Past Board Member, 2023–2026)
Chris McConnell, Principal

Proudly Affiliated With

IIBEC Southern Ontario Chapter Logo

IIBEC Southern Ontario

Building Science Association of Ontario Logo

Building Science Association of Ontario (BSAO)

Our active leadership and memberships within the IIBEC Southern Ontario Chapter and the BSAO underscore our commitment to technical excellence, ethical consulting, and continuous education. By staying at the forefront of industry advocacy, MDS Building Science Inc. ensures our clients benefit from the latest standards and best practices.

Start Your Project

Ready to assess your building's health? Get in touch with our team.

55 Village Centre Place, Suite 200, Mississauga, Ontario, L4Z 1V9

+1 (647) 933-9807