Most moisture problems within building envelopes are typically due to rainwater leakage or condensation associated with breaches in the air barrier, water resistive barrier, vapor retarder, and insulation control layers. Roof to wall interface conditions are one of the most difficult and frequently overlooked contributors to such problems. In general, envelope systems today are lighter, tighter, and better insulated that their predecessors because of energy codes, construction costs, and operating costs. As a result, these new wall systems are often less forgiving than the lesser insulated of the past. This is because older systems, such as masonry mass wall systems, had greater heat transfer and therefore greater drying potential and could often store small amounts of moisture without damage. Therefore, understanding proper integration of control layers at such interfaces is more important than ever. This presentation will review details to maintain the integrity of these control layers at roof to wall interface conditions.  

Learning Objective 1 – Sumarize the function of air barrier, water resistive barrier, vapor retarder, and insulation control layers.

Learning Objective 2 – Identify common breaches in the congtrol layers at roof to wall interface conditions. 

Learning Objective 3 - Describe common approaches for maintaining the continuity of the four control layers. 

Learning Objective 4 - Develop details to implement these basic approaches at roof to wall interfaces in building assemblies.

About the Speaker:

 Norbert V. Krogstad is a licensed architect in Illinois, Minnesota, Missouri, and Oklahoma. During the past 37 years at WJE, Mr. Krogstad has investigated and developed repairs for distressed conditions in several hundred new and existing buildings. Most of Mr. Krogstad’s projects involve exterior wall assemblies with condensation, water leakage or other moisture intrusion problems. Mr. Krogstad has lectured at numerous conferences and continuing education programs on topics related to water leakage, condensation, deterioration, and structural problems in masonry and other building cladding systems. He has also authored or co-authored many papers and articles related to masonry wall system problems, condensation problems, and the design or investigation of building wall systems in multiple technical publications. This includes a question and answer column called “Troubleshooting” in Masonry Construction magazine that Mr. Krogstad authored from 1989 to 2011. Mr. Krogstad is a member of the ASTM International (ASTM) where he is active on several committees concerning masonry wall systems. He was also on the ASHRAE Task Group that developed Standard 160 - Criteria for Moisture-Control Design Analysis in Buildings.