2026 BES Session: Thicker Roofs, Tighter Constraints: Designing Code-Compliant Steep-Slope Roof Retrofits (Williams C., Dunn K.)

2026 BES Session: Thicker Roofs, Tighter Constraints: Designing Code-Compliant Steep-Slope Roof Retrofits

(Williams C., Dunn K.)

Course Overview
This session was originally presented at the 2026 IIBEC Building Enclosure Symposium in Indianapolis, Indiana.  This course includes the following components:

• recording of the live session
• a summative assessment consisting of 10 multiple-choice questions
• two surveys required to claim continuing education credit

Description
Designing replacement steep-slope roofs for existing buildings has become a balancing act, as designers must meet increasingly stringent energy codes while incorporating prescriptive code requirements for ventilation and a thermal barrier, all within the fixed geometry of existing roof profiles. To reconcile these constraints, designers are increasingly turning to split-insulation assemblies with integrated ventilation strategies. These solutions, however, can introduce new risks—particularly related to moisture accumulation, air leakage, and concealed water intrusion—that must be mitigated through careful material selection and detailed design. Steep-slope insulated and ventilated roof replacement designs are highly project-specific, and each design decision carries implications beyond energy performance alone. Designers and building owners must evaluate how insulation and ventilation configurations affect roof moisture management, the location and continuity of air and vapor barriers, cost, constructability, aesthetics, occupant impacts, and other factors to select the best approach for each building.  This session outlines key code requirements and explores critical design considerations for insulated and ventilated steep-slope roof replacements through several case studies, highlighting common challenges, trade-offs, and lessons learned, and by offering designers a practical framework to navigate the evolving complexities of steep-slope roof replacement.

Speaker/Author

Casey Williams, PE
Associate Principal
Simpson Gumpertz & Heger

Kelsey Dunn, PE
Senior Project Manager
Simpson Gumpertz & Heger

Course Access
Courses are accessible in LearnUpon for one year from the date of purchase.

Course Recommended Prerequisite(s)

• Attendees should have an understanding of common roof assemblies and components, as well as knowledge of the functions of air, vapor, and thermal barriers.

IIBEC Core Competencies: 

Roofing

Knowledge Level: 

Intermediate (5–15 years)

Disclaimer
The views and opinions expressed in the session content at the 2026 IIBEC Building Enclosure Symposium are those of the content author(s)/speaker(s) and do not necessarily reflect the policies or positions of the International Institute of Building Enclosure Consultants (IIBEC). IIBEC makes no warranty, whether express or implied, as to the completeness, accuracy or validity of the information provided.

Credit Start Date August 17, 2026          
Credit Expiration Date  August 17, 2029

Continuing Education Credit Statement
This course is approved for 1.0 IIBEC CEH
This course is approved for 1.0 AIA LU/HSW
AIA Course Number: BES26_09_OD
AIA Provider Number: G024

Continuing Education Credit Claim Information

To claim IIBEC CEHs and download a Certificate of Completion, learners are required to complete all components of the course, including a passing score of 70% or higher on the summative assessment.  Participants are provided unlimited attempts to complete the summative assessment with a passing score of 70% or higher.

• After completing the course requirements download a Certificate of Completion. 
• Participants are responsible for self-reporting IIBEC CEH credit by uploading their Certificate of Completion to their IIBEC Portal. For assistance in self-reporting CEHs, please reach out to: cehs@iibec.org
• If you are a member of AIA and would like IIBEC to report your participation in the course to AIA, there is a place in the course evaluation survey to input your AIA member number.

AIA CES Provider statement

IIBEC is a registered provider of AIA-approved continuing education under Provider G024. All registered AIA CES Providers must comply with the AIA Standards for Continuing Education Programs.  Any questions or concerns about this provider or this learning program may be sent to AIA CES (cessupport@aia.org or (800) AIA 3837, Option 3).

This learning program is registered with AIA CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. AIA continuing education credit has been reviewed and approved by AIA CES. Learners must complete the entire learning program to receive continuing education credit. AIA continuing education Learning Units earned upon completion of this course will be reported to AIA CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request.